diff --git a/man/systemd.network.xml b/man/systemd.network.xml index bcf6b36eed..d4f0342746 100644 --- a/man/systemd.network.xml +++ b/man/systemd.network.xml @@ -28,8 +28,8 @@ Description - A plain ini-style text file that encodes network configuration for matching network interfaces, - used by + A plain ini-style text file that encodes network configuration for matching network + interfaces, used by systemd-networkd8. See systemd.syntax7 for a general description of the syntax. @@ -41,13 +41,14 @@ directories /usr/lib/systemd/network and /usr/local/lib/systemd/network, the volatile runtime network directory /run/systemd/network and the local administration network directory - /etc/systemd/network. All configuration files are collectively sorted and processed - in lexical order, regardless of the directories in which they live. However, files with identical - filenames replace each other. Files in /etc/ have the highest priority, files in - /run/ take precedence over files with the same name under - /usr/. This can be used to override a system-supplied configuration file with a local - file if needed. As a special case, an empty file (file size 0) or symlink with the same name pointing to - /dev/null disables the configuration file entirely (it is "masked"). + /etc/systemd/network. All configuration files are collectively sorted and + processed in lexical order, regardless of the directories in which they live. However, files with + identical filenames replace each other. Files in /etc/ have the highest + priority, files in /run/ take precedence over files with the same name under + /usr/. This can be used to override a system-supplied configuration file with + a local file if needed. As a special case, an empty file (file size 0) or symlink with the same + name pointing to /dev/null disables the configuration file entirely (it is + "masked"). Along with the network file foo.network, a "drop-in" directory foo.network.d/ may exist. All files with the suffix @@ -67,74 +68,71 @@ [Match] Section Options - The network file contains a [Match] section, which determines if a given network file may be - applied to a given device; and a [Network] section specifying how the device should be configured. The - first (in lexical order) of the network files that matches a given device is applied, all later files - are ignored, even if they match as well. + The network file contains a [Match] section, which determines if a given network file may + be applied to a given device; and a [Network] section specifying how the device should be + configured. The first (in lexical order) of the network files that matches a given device is + applied, all later files are ignored, even if they match as well. - A network file is said to match a network interface if all matches specified by the [Match] - section are satisfied. When a network file does not contain valid settings in [Match] section, then the - file will match all interfaces and systemd-networkd warns about that. Hint: to avoid - the warning and to make it clear that all interfaces shall be matched, add the following: - Name=* The following keys are accepted: + A network file is said to match a network interface if all matches specified by the [Match] + section are satisfied. When a network file does not contain valid settings in [Match] section, then + the file will match all interfaces and systemd-networkd warns about that. Hint: + to avoid the warning and to make it clear that all interfaces shall be matched, add the following: + Name=* The following keys are accepted: - - - - - - - + + + + + + + - - Name= - - A whitespace-separated list of shell-style globs matching the device name, as exposed - by the udev property INTERFACE, or device's alternative names. If the - list is prefixed with a "!", the test is inverted. - - + + Name= + + A whitespace-separated list of shell-style globs matching the device name, as exposed + by the udev property INTERFACE, or device's alternative names. If the + list is prefixed with a "!", the test is inverted. + + - - WLANInterfaceType= - - A whitespace-separated list of wireless network type. Supported values are - ad-hoc, station, ap, - ap-vlan, wds, monitor, - mesh-point, p2p-client, p2p-go, - p2p-device, ocb, and nan. If the - list is prefixed with a "!", the test is inverted. - - - + + WLANInterfaceType= + + A whitespace-separated list of wireless network type. Supported values are + ad-hoc, station, ap, + ap-vlan, wds, monitor, + mesh-point, p2p-client, p2p-go, + p2p-device, ocb, and nan. If the + list is prefixed with a "!", the test is inverted. + + - - SSID= - - A whitespace-separated list of shell-style globs matching the SSID of the currently - connected wireless LAN. If the list is prefixed with a "!", the test is inverted. - - - + + SSID= + + A whitespace-separated list of shell-style globs matching the SSID of the currently + connected wireless LAN. If the list is prefixed with a "!", the test is inverted. + + - - BSSID= - - A whitespace-separated list of hardware address of the currently connected wireless - LAN. Use full colon-, hyphen- or dot-delimited hexadecimal. See the example in - MACAddress=. This option may appear more than once, in which case the - lists are merged. If the empty string is assigned to this option, the list is reset. - - - - - - - - - - + + BSSID= + + A whitespace-separated list of hardware address of the currently connected wireless + LAN. Use full colon-, hyphen- or dot-delimited hexadecimal. See the example in + MACAddress=. This option may appear more than once, in which case the + lists are merged. If the empty string is assigned to this option, the list is reset. + + + + + + + + + @@ -149,16 +147,17 @@ The hardware address to set for the device. + MTUBytes= - The maximum transmission unit in bytes to set for the - device. The usual suffixes K, M, G, are supported and are - understood to the base of 1024. - Note that if IPv6 is enabled on the interface, and the MTU is chosen - below 1280 (the minimum MTU for IPv6) it will automatically be increased to this value. + The maximum transmission unit in bytes to set for the device. The usual suffixes K, M, + G, are supported and are understood to the base of 1024. + Note that if IPv6 is enabled on the interface, and the MTU is chosen below 1280 (the + minimum MTU for IPv6) it will automatically be increased to this value. + ARP= @@ -170,118 +169,131 @@ the network otherwise. Defaults to unset. + Multicast= - Takes a boolean. If set to true, the multicast flag on the device is enabled. Defaults to unset. + Takes a boolean. If set to true, the multicast flag on the device is enabled. Defaults + to unset. + AllMulticast= - Takes a boolean. If set to true, the driver retrieves all multicast packets from the network. - This happens when multicast routing is enabled. Defaults to unset. + Takes a boolean. If set to true, the driver retrieves all multicast packets from the + network. This happens when multicast routing is enabled. Defaults to unset. + Promiscuous= - Takes a boolean. If set to true, promiscuous mode of the interface is enabled. - Defaults to unset. - If this is set to false for the underlying link of a passthru mode MACVLAN/MACVTAP, - the virtual interface will be created with the nopromisc flag set. + Takes a boolean. If set to true, promiscuous mode of the interface is enabled. Defaults + to unset. + If this is set to false for the underlying link of a passthru mode + MACVLAN/MACVTAP, the virtual interface will be created with the nopromisc + flag set. + Unmanaged= - Takes a boolean. When yes, no attempts are - made to bring up or configure matching links, equivalent to - when there are no matching network files. Defaults to + Takes a boolean. When yes, no attempts are made to bring up or + configure matching links, equivalent to when there are no matching network files. Defaults to no. - This is useful for preventing later matching network - files from interfering with certain interfaces that are fully - controlled by other applications. + This is useful for preventing later matching network files from interfering with + certain interfaces that are fully controlled by other applications. + Group= - Link groups are similar to port ranges found in managed switches. When network interfaces - are added to a numbered group, operations on all the interfaces from that group can be - performed at once. Takes an unsigned integer in the range 0…2147483647. Defaults to unset. - + Link groups are similar to port ranges found in managed switches. When network + interfaces are added to a numbered group, operations on all the interfaces from that group + can be performed at once. Takes an unsigned integer in the range 0…2147483647. Defaults to + unset. + RequiredForOnline= - Takes a boolean or a minimum operational state and an optional maximum operational state. - Please see networkctl1 - for possible operational states. When yes, the network is deemed required when - determining whether the system is online (including when running - systemd-networkd-wait-online). When no, the network is ignored - when determining the online state. When a minimum operational state and an optional maximum operational - state are set, yes is implied, and this controls the minimum and maximum - operational state required for the network interface to be considered online. + Takes a boolean or a minimum operational state and an optional maximum operational + state. Please see + networkctl1 + for possible operational states. When yes, the network is deemed required + when determining whether the system is online (including when running + systemd-networkd-wait-online). When no, the network is + ignored when determining the online state. When a minimum operational state and an optional + maximum operational state are set, yes is implied, and this controls the + minimum and maximum operational state required for the network interface to be considered + online. - Defaults to yes when ActivationPolicy= is not set, - or set to up, always-up, or bound. - Defaults to no when ActivationPolicy= is set to - manual or down. This is forced to no - when ActivationPolicy= is set to always-down. + Defaults to yes when ActivationPolicy= is not + set, or set to up, always-up, or + bound. Defaults to no when + ActivationPolicy= is set to manual or + down. This is forced to no when + ActivationPolicy= is set to always-down. - The network will be brought up normally (as configured by ActivationPolicy=), - but in the event that there is no address being assigned by DHCP or the - cable is not plugged in, the link will simply remain offline and be - skipped automatically by systemd-networkd-wait-online - if RequiredForOnline=no. + The network will be brought up normally (as configured by + ActivationPolicy=), but in the event that there is no address being + assigned by DHCP or the cable is not plugged in, the link will simply remain offline and be + skipped automatically by systemd-networkd-wait-online if + RequiredForOnline=no. + RequiredFamilyForOnline= - Takes an address family. When specified, an IP address in the given family is deemed required - when determining whether the link is online (including when running + Takes an address family. When specified, an IP address in the given family is deemed + required when determining whether the link is online (including when running systemd-networkd-wait-online). Takes one of ipv4, ipv6, both, or any. Defaults to any. Note that this option has no effect if - RequiredForOnline=no, or if RequiredForOnline= specifies a - minimum operational state below degraded. + RequiredForOnline=no, or if RequiredForOnline= + specifies a minimum operational state below degraded. + ActivationPolicy= Specifies the policy for systemd-networkd managing the link administrative state. Specifically, this controls how systemd-networkd changes the network device's IFF_UP flag, which is sometimes - controlled by system administrators by running e.g., ip link set dev eth0 up - or ip link set dev eth0 down, and can also be changed with - networkctl up eth0 or networkctl down eth0. + controlled by system administrators by running e.g., + ip link set dev eth0 up or ip link set dev eth0 down, + and can also be changed with networkctl up eth0 or + networkctl down eth0. Takes one of up, always-up, manual, always-down, down, - or bound. When manual, systemd-networkd - will not change the link's admin state automatically; the system administrator must bring the - interface up or down manually, as desired. When up (the default) or - always-up, or down or always-down, - systemd-networkd will set the link up or down, respectively, - when the interface is (re)configured. When always-up or - always-down, systemd-networkd will set the link up - or down, respectively, any time systemd-networkd detects a change in - the administrative state. When BindCarrier= is also set, this is - automatically set to bound and any other value is ignored. + or bound. When manual, + systemd-networkd will not change the link's admin state automatically; + the system administrator must bring the interface up or down manually, as desired. When + up (the default) or always-up, or + down or always-down, + systemd-networkd will set the link up or down, respectively, when the + interface is (re)configured. When always-up or + always-down, systemd-networkd will set the link up or + down, respectively, any time systemd-networkd detects a change in the + administrative state. When BindCarrier= is also set, this is automatically + set to bound and any other value is ignored. - When the policy is set to down or manual, - the default value of RequiredForOnline= is no. - When the policy is set to always-down, the value of + When the policy is set to down or manual, the + default value of RequiredForOnline= is no. When the + policy is set to always-down, the value of RequiredForOnline= forced to no. The administrative state is not the same as the carrier state, so using - always-up does not mean the link will never lose carrier. The link - carrier depends on both the administrative state as well as the network device's physical - connection. However, to avoid reconfiguration failures, when using always-up, + always-up does not mean the link will never lose carrier. The link carrier + depends on both the administrative state as well as the network device's physical connection. + However, to avoid reconfiguration failures, when using always-up, IgnoreCarrierLoss= is forced to true. @@ -289,668 +301,707 @@ - [SR-IOV] Section Options - The [SR-IOV] section accepts the following keys. Specify several [SR-IOV] sections to configure - several SR-IOVs. SR-IOV provides the ability to partition a single physical PCI resource into virtual - PCI functions which can then be injected into a VM. In the case of network VFs, SR-IOV improves - north-south network performance (that is, traffic with endpoints outside the host machine) by allowing - traffic to bypass the host machine’s network stack. + [SR-IOV] Section Options + The [SR-IOV] section accepts the following keys. Specify several [SR-IOV] sections to + configure several SR-IOVs. SR-IOV provides the ability to partition a single physical PCI resource + into virtual PCI functions which can then be injected into a VM. In the case of network VFs, SR-IOV + improves north-south network performance (that is, traffic with endpoints outside the host machine) + by allowing traffic to bypass the host machine’s network stack. - - - VirtualFunction= - - Specifies a Virtual Function (VF), lightweight PCIe function designed solely to move data - in and out. Takes an unsigned integer in the range 0…2147483646. This option is compulsory. - - + + + VirtualFunction= + + Specifies a Virtual Function (VF), lightweight PCIe function designed solely to move + data in and out. Takes an integer in the range 0…2147483646. This option is compulsory. + + + - - VLANId= - - Specifies VLAN ID of the virtual function. Takes an unsigned integer in the range 1…4095. - - + + VLANId= + + Specifies VLAN ID of the virtual function. Takes an integer in the range 1…4095. + + - - QualityOfService= - - Specifies quality of service of the virtual function. Takes an unsigned integer in the range 1…4294967294. - - + + QualityOfService= + + Specifies quality of service of the virtual function. Takes an integer in the range + 1…4294967294. + + - - VLANProtocol= - - Specifies VLAN protocol of the virtual function. Takes 802.1Q or - 802.1ad. - - + + VLANProtocol= + + Specifies VLAN protocol of the virtual function. Takes 802.1Q or + 802.1ad. + + - - MACSpoofCheck= - - Takes a boolean. Controls the MAC spoof checking. When unset, the kernel's default will be used. - - + + MACSpoofCheck= + + Takes a boolean. Controls the MAC spoof checking. When unset, the kernel's default will + be used. + + - - QueryReceiveSideScaling= - - Takes a boolean. Toggle the ability of querying the receive side scaling (RSS) - configuration of the virtual function (VF). The VF RSS information like RSS hash key may be - considered sensitive on some devices where this information is shared between VF and the - physical function (PF). When unset, the kernel's default will be used. - - + + QueryReceiveSideScaling= + + Takes a boolean. Toggle the ability of querying the receive side scaling (RSS) + configuration of the virtual function (VF). The VF RSS information like RSS hash key may be + considered sensitive on some devices where this information is shared between VF and the + physical function (PF). When unset, the kernel's default will be used. + + - - Trust= - - Takes a boolean. Allows to set trust mode of the virtual function (VF). When set, VF - users can set a specific feature which may impact security and/or performance. When unset, - the kernel's default will be used. - - + + Trust= + + Takes a boolean. Allows to set trust mode of the virtual function (VF). When set, VF + users can set a specific feature which may impact security and/or performance. When unset, + the kernel's default will be used. + + - - LinkState= - - Allows to set the link state of the virtual function (VF). Takes a boolean or a - special value auto. Setting to auto means a - reflection of the physical function (PF) link state, yes lets the VF to - communicate with other VFs on this host even if the PF link state is down, - no causes the hardware to drop any packets sent by the VF. When unset, - the kernel's default will be used. - - + + LinkState= + + Allows to set the link state of the virtual function (VF). Takes a boolean or a + special value auto. Setting to auto means a + reflection of the physical function (PF) link state, yes lets the VF to + communicate with other VFs on this host even if the PF link state is down, + no causes the hardware to drop any packets sent by the VF. When unset, + the kernel's default will be used. + + - - MACAddress= - - Specifies the MAC address for the virtual function. - - - + + MACAddress= + + Specifies the MAC address for the virtual function. + + + [Network] Section Options - The [Network] section accepts the following keys: + The [Network] section accepts the following keys: - - - Description= - - A description of the device. This is only used for - presentation purposes. - - - - DHCP= - - Enables DHCPv4 and/or DHCPv6 client support. Accepts - yes, no, - ipv4, or ipv6. Defaults - to no. + + + Description= + + A description of the device. This is only used for presentation purposes. + + - Note that DHCPv6 will by default be triggered by Router - Advertisement, if that is enabled, regardless of this parameter. - By enabling DHCPv6 support explicitly, the DHCPv6 client will - be started regardless of the presence of routers on the link, - or what flags the routers pass. See - IPv6AcceptRA=. - - Furthermore, note that by default the domain name - specified through DHCP is not used for name resolution. - See option below. - - See the [DHCPv4] or [DHCPv6] sections below for further configuration options for the DHCP - client support. - - - - DHCPServer= - - Takes a boolean. If set to yes, DHCPv4 server will be started. Defaults - to no. Further settings for the DHCP server may be set in the [DHCPServer] - section described below. - - - - LinkLocalAddressing= - - Enables link-local address autoconfiguration. Accepts , - , , and . An IPv6 link-local address - is configured when or . An IPv4 link-local address is - configured when or and when DHCPv4 autoconfiguration - has been unsuccessful for some time. (IPv4 link-local address autoconfiguration will usually - happen in parallel with repeated attempts to acquire a DHCPv4 lease). - - Defaults to when KeepMaster= or - Bridge= is set or when the specified - MACVLAN=/MACVTAP= has Mode=passthru, or - otherwise. - - - - IPv6LinkLocalAddressGenerationMode= - - Specifies how IPv6 link local address is generated. Takes one of - eui64, none, stable-privacy and - random. When unset, stable-privacy is used if - IPv6StableSecretAddress= is specified, and if not, - eui64 is used. Note that if LinkLocalAddressing= is - no or ipv4, then - IPv6LinkLocalAddressGenerationMode= will be ignored. Also, even if - LinkLocalAddressing= is yes or - ipv6, setting IPv6LinkLocalAddressGenerationMode=none - disables to configure an IPv6 link-local address. - - - - IPv6StableSecretAddress= - - Takes an IPv6 address. The specified address will be used as a stable secret for - generating IPv6 link-local address. If this setting is specified, and - IPv6LinkLocalAddressGenerationMode= is unset, then - IPv6LinkLocalAddressGenerationMode=stable-privacy is implied. - If this setting is not specified, and stable-privacy is set to - IPv6LinkLocalAddressGenerationMode=, - then a stable secret address will be generated from the local machine ID and the interface - name. - - - - IPv4LLRoute= - - Takes a boolean. If set to true, sets up the route needed for - non-IPv4LL hosts to communicate with IPv4LL-only hosts. Defaults - to false. - - - - - DefaultRouteOnDevice= - - Takes a boolean. If set to true, sets up the default route bound to the interface. - Defaults to false. This is useful when creating routes on point-to-point interfaces. - This is equivalent to e.g. the following, - ip route add default dev veth99 - or, - [Route] -Gateway=0.0.0.0 - Currently, there are no way to specify e.g., the table for the route configured by - this setting. To configure the default route with such an additional property, please use - the following instead: - [Route] -Gateway=0.0.0.0 -Table=1234 - - - - LLMNR= - - Takes a boolean or resolve. When true, - enables Link-Local - Multicast Name Resolution on the link. When set to - resolve, only resolution is enabled, - but not host registration and announcement. Defaults to - true. This setting is read by - systemd-resolved.service8. - - - - MulticastDNS= - - Takes a boolean or resolve. When true, - enables Multicast - DNS support on the link. When set to - resolve, only resolution is enabled, - but not host or service registration and - announcement. Defaults to false. This setting is read by - systemd-resolved.service8. - - - - DNSOverTLS= - - Takes a boolean or opportunistic. When true, enables - DNS-over-TLS support on the link. - When set to opportunistic, compatibility with non-DNS-over-TLS servers - is increased, by automatically turning off DNS-over-TLS servers in this case. This option - defines a per-interface setting for - resolved.conf5's - global DNSOverTLS= option. Defaults to unset, and the global setting - will be used. This setting is read by - systemd-resolved.service8. - - - - DNSSEC= - - Takes a boolean or allow-downgrade. When true, enables - DNSSEC DNS validation support on - the link. When set to allow-downgrade, compatibility with non-DNSSEC - capable networks is increased, by automatically turning off DNSSEC in this case. This - option defines a per-interface setting for - resolved.conf5's - global DNSSEC= option. Defaults to unset, and the global setting will be - used. This setting is read by - systemd-resolved.service8. - - - - - DNSSECNegativeTrustAnchors= - A space-separated list of DNSSEC negative - trust anchor domains. If specified and DNSSEC is enabled, - look-ups done via the interface's DNS server will be subject - to the list of negative trust anchors, and not require - authentication for the specified domains, or anything below - it. Use this to disable DNSSEC authentication for specific - private domains, that cannot be proven valid using the - Internet DNS hierarchy. Defaults to the empty list. This - setting is read by - systemd-resolved.service8. - - - - LLDP= - - Controls support for Ethernet LLDP packet reception. LLDP is a link-layer protocol commonly - implemented on professional routers and bridges which announces which physical port a system is connected - to, as well as other related data. Accepts a boolean or the special value - routers-only. When true, incoming LLDP packets are accepted and a database of all LLDP - neighbors maintained. If routers-only is set only LLDP data of various types of routers - is collected and LLDP data about other types of devices ignored (such as stations, telephones and - others). If false, LLDP reception is disabled. Defaults to routers-only. Use - networkctl1 to query the - collected neighbor data. LLDP is only available on Ethernet links. See EmitLLDP= below - for enabling LLDP packet emission from the local system. - - - - - EmitLLDP= - - Controls support for Ethernet LLDP packet emission. Accepts a boolean parameter or the special values - nearest-bridge, non-tpmr-bridge and - customer-bridge. Defaults to false, which turns off LLDP packet emission. If not false, - a short LLDP packet with information about the local system is sent out in regular intervals on the - link. The LLDP packet will contain information about the local hostname, the local machine ID (as stored - in machine-id5) and the - local interface name, as well as the pretty hostname of the system (as set in - machine-info5). LLDP - emission is only available on Ethernet links. Note that this setting passes data suitable for - identification of host to the network and should thus not be enabled on untrusted networks, where such - identification data should not be made available. Use this option to permit other systems to identify on - which interfaces they are connected to this system. The three special values control propagation of the - LLDP packets. The nearest-bridge setting permits propagation only to the nearest - connected bridge, non-tpmr-bridge permits propagation across Two-Port MAC Relays, but - not any other bridges, and customer-bridge permits propagation until a customer bridge - is reached. For details about these concepts, see IEEE 802.1AB-2016. Note that - configuring this setting to true is equivalent to nearest-bridge, the recommended and - most restricted level of propagation. See LLDP= above for an option to enable LLDP - reception. - - - - - BindCarrier= - - A link name or a list of link names. When set, controls the behavior of the current - link. When all links in the list are in an operational down state, the current link is brought - down. When at least one link has carrier, the current interface is brought up. - - This forces ActivationPolicy= to be set to bound. - - - - Address= - - A static IPv4 or IPv6 address and its prefix length, - separated by a / character. Specify - this key more than once to configure several addresses. - The format of the address must be as described in - inet_pton3. - This is a short-hand for an [Address] section only - containing an Address key (see below). This option may be - specified more than once. - - - If the specified address is 0.0.0.0 (for IPv4) or :: - (for IPv6), a new address range of the requested size is automatically allocated from a - system-wide pool of unused ranges. Note that the prefix length must be equal or larger than 8 for - IPv4, and 64 for IPv6. The allocated range is checked against all current network interfaces and - all known network configuration files to avoid address range conflicts. The default system-wide - pool consists of 192.168.0.0/16, 172.16.0.0/12 and 10.0.0.0/8 for IPv4, and fd00::/8 for IPv6. - This functionality is useful to manage a large number of dynamically created network interfaces - with the same network configuration and automatic address range assignment. - - - - - Gateway= - - The gateway address, which must be in the format - described in - inet_pton3. - This is a short-hand for a [Route] section only containing - a Gateway key. This option may be specified more than - once. - - - - DNS= - - A DNS server address, which must be in the format described in - inet_pton3. - This option may be specified more than once. Each address can optionally take a port number - separated with :, a network interface name or index separated with - %, and a Server Name Indication (SNI) separated with #. - When IPv6 address is specified with a port number, then the address must be in the square - brackets. That is, the acceptable full formats are - 111.222.333.444:9953%ifname#example.com for IPv4 and - [1111:2222::3333]:9953%ifname#example.com for IPv6. If an empty string is - assigned, then the all previous assignments are cleared. This setting is read by - systemd-resolved.service8. - - - - Domains= - - A whitespace-separated list of domains which should be resolved using the DNS servers on - this link. Each item in the list should be a domain name, optionally prefixed with a tilde - (~). The domains with the prefix are called "routing-only domains". The - domains without the prefix are called "search domains" and are first used as search suffixes for - extending single-label hostnames (hostnames containing no dots) to become fully qualified - domain names (FQDNs). If a single-label hostname is resolved on this interface, each of the - specified search domains are appended to it in turn, converting it into a fully qualified domain - name, until one of them may be successfully resolved. - - Both "search" and "routing-only" domains are used for routing of DNS queries: look-ups for hostnames - ending in those domains (hence also single label names, if any "search domains" are listed), are routed to - the DNS servers configured for this interface. The domain routing logic is particularly useful on - multi-homed hosts with DNS servers serving particular private DNS zones on each interface. - - The "routing-only" domain ~. (the tilde indicating definition of a routing domain, - the dot referring to the DNS root domain which is the implied suffix of all valid DNS names) has special - effect. It causes all DNS traffic which does not match another configured domain routing entry to be routed - to DNS servers specified for this interface. This setting is useful to prefer a certain set of DNS servers - if a link on which they are connected is available. - - This setting is read by - systemd-resolved.service8. - "Search domains" correspond to the domain and search entries in - resolv.conf5. - Domain name routing has no equivalent in the traditional glibc API, which has no concept of domain - name servers limited to a specific link. - - - - DNSDefaultRoute= - - Takes a boolean argument. If true, this link's configured DNS servers are used for resolving domain - names that do not match any link's configured Domains= setting. If false, this link's - configured DNS servers are never used for such domains, and are exclusively used for resolving names that - match at least one of the domains configured on this link. If not specified defaults to an automatic mode: - queries not matching any link's configured domains will be routed to this link if it has no routing-only - domains configured. - - - - NTP= - - An NTP server address (either an IP address, or a hostname). This option may be specified more than once. This setting is read by - systemd-timesyncd.service8. - - - - IPForward= - Configures IP packet forwarding for the - system. If enabled, incoming packets on any network - interface will be forwarded to any other interfaces - according to the routing table. Takes a boolean, - or the values ipv4 or - ipv6, which only enable IP packet - forwarding for the specified address family. This controls - the net.ipv4.ip_forward and - net.ipv6.conf.all.forwarding sysctl - options of the network interface (see ip-sysctl.txt - for details about sysctl options). Defaults to + + DHCP= + + Enables DHCPv4 and/or DHCPv6 client support. Accepts yes, + no, ipv4, or ipv6. Defaults to no. - Note: this setting controls a global kernel option, - and does so one way only: if a network that has this setting - enabled is set up the global setting is turned on. However, - it is never turned off again, even after all networks with - this setting enabled are shut down again. + Note that DHCPv6 will by default be triggered by Router Advertisement, if that is + enabled, regardless of this parameter. By enabling DHCPv6 support explicitly, the DHCPv6 + client will be started regardless of the presence of routers on the link, or what flags the + routers pass. See IPv6AcceptRA=. - To allow IP packet forwarding only between specific - network interfaces use a firewall. - - - - IPMasquerade= - Configures IP masquerading for the network interface. If enabled, packets - forwarded from the network interface will be appear as coming from the local host. Takes one - of ipv4, ipv6, both, or + Furthermore, note that by default the domain name specified through DHCP is not used + for name resolution. See option below. + + See the [DHCPv4] or [DHCPv6] sections below for further configuration options for the + DHCP client support. + + + + + DHCPServer= + + Takes a boolean. If set to yes, DHCPv4 server will be started. + Defaults to no. Further settings for the DHCP server may be set in the + [DHCPServer] section described below. + + + + + LinkLocalAddressing= + + Enables link-local address autoconfiguration. Accepts , + , , and . An IPv6 link-local + address is configured when or . An IPv4 link-local + address is configured when or and when DHCPv4 + autoconfiguration has been unsuccessful for some time. (IPv4 link-local address + autoconfiguration will usually happen in parallel with repeated attempts to acquire a DHCPv4 + lease). + + Defaults to when KeepMaster= or + Bridge= is set or when the specified + MACVLAN=/MACVTAP= has Mode=passthru, + or otherwise. + + + + + IPv6LinkLocalAddressGenerationMode= + + Specifies how IPv6 link local address is generated. Takes one of + eui64, none, stable-privacy and + random. When unset, stable-privacy is used if + IPv6StableSecretAddress= is specified, and if not, + eui64 is used. Note that if LinkLocalAddressing= is + no or ipv4, then + IPv6LinkLocalAddressGenerationMode= will be ignored. Also, even if + LinkLocalAddressing= is yes or ipv6, + setting IPv6LinkLocalAddressGenerationMode=none + disables to configure an IPv6 link-local address. + + + + + IPv6StableSecretAddress= + + Takes an IPv6 address. The specified address will be used as a stable secret for + generating IPv6 link-local address. If this setting is specified, and + IPv6LinkLocalAddressGenerationMode= is unset, then + IPv6LinkLocalAddressGenerationMode=stable-privacy is implied. + If this setting is not specified, and stable-privacy is set to + IPv6LinkLocalAddressGenerationMode=, + then a stable secret address will be generated from the local machine ID and the interface + name. + + + + + IPv4LLRoute= + + Takes a boolean. If set to true, sets up the route needed for non-IPv4LL hosts to + communicate with IPv4LL-only hosts. Defaults to false. + + + + + DefaultRouteOnDevice= + + Takes a boolean. If set to true, sets up the default route bound to the interface. + Defaults to false. This is useful when creating routes on point-to-point interfaces. This is + equivalent to e.g. the following, + ip route add default dev veth99 + or, + [Route] +Gateway=0.0.0.0 + Currently, there are no way to specify e.g., the table for the route configured by this + setting. To configure the default route with such an additional property, please use the + following instead: + [Route] +Gateway=0.0.0.0 +Table=1234 + + + + + LLMNR= + + Takes a boolean or resolve. When true, enables + Link-Local Multicast Name Resolution + on the link. When set to resolve, only resolution is enabled, but not host + registration and announcement. Defaults to true. This setting is read by + systemd-resolved.service8. + + + + + + MulticastDNS= + + Takes a boolean or resolve. When true, enables + Multicast DNS support on the link. + When set to resolve, only resolution is enabled, but not host or service + registration and announcement. Defaults to false. This setting is read by + systemd-resolved.service8. + + + + + + DNSOverTLS= + + Takes a boolean or opportunistic. When true, enables + DNS-over-TLS support on the link. + When set to opportunistic, compatibility with non-DNS-over-TLS servers is + increased, by automatically turning off DNS-over-TLS servers in this case. This option + defines a per-interface setting for + resolved.conf5's + global DNSOverTLS= option. Defaults to unset, and the global setting will + be used. This setting is read by + systemd-resolved.service8. + + + + + + DNSSEC= + + Takes a boolean or allow-downgrade. When true, enables + DNSSEC DNS validation support on the + link. When set to allow-downgrade, compatibility with non-DNSSEC capable + networks is increased, by automatically turning off DNSSEC in this case. This option defines + a per-interface setting for + resolved.conf5's + global DNSSEC= option. Defaults to unset, and the global setting will be + used. This setting is read by + systemd-resolved.service8. + + + + + + DNSSECNegativeTrustAnchors= + + A space-separated list of DNSSEC negative trust anchor domains. If specified and DNSSEC + is enabled, look-ups done via the interface's DNS server will be subject to the list of + negative trust anchors, and not require authentication for the specified domains, or anything + below it. Use this to disable DNSSEC authentication for specific private domains, that cannot + be proven valid using the Internet DNS hierarchy. Defaults to the empty list. This setting is + read by + systemd-resolved.service8. + + + + + + LLDP= + + Controls support for Ethernet LLDP packet reception. LLDP is a link-layer protocol + commonly implemented on professional routers and bridges which announces which physical port + a system is connected to, as well as other related data. Accepts a boolean or the special + value routers-only. When true, incoming LLDP packets are accepted and a + database of all LLDP neighbors maintained. If routers-only is set only + LLDP data of various types of routers is collected and LLDP data about other types of devices + ignored (such as stations, telephones and others). If false, LLDP reception is disabled. + Defaults to routers-only. Use + networkctl1 + to query the collected neighbor data. LLDP is only available on Ethernet links. See + EmitLLDP= below for enabling LLDP packet emission from the local system. + + + + + + EmitLLDP= + + Controls support for Ethernet LLDP packet emission. Accepts a boolean parameter or the + special values nearest-bridge, non-tpmr-bridge and + customer-bridge. Defaults to false, which turns off LLDP packet emission. + If not false, a short LLDP packet with information about the local system is sent out in + regular intervals on the link. The LLDP packet will contain information about the local + hostname, the local machine ID (as stored in + machine-id5) + and the local interface name, as well as the pretty hostname of the system (as set in + machine-info5). + LLDP emission is only available on Ethernet links. Note that this setting passes data + suitable for identification of host to the network and should thus not be enabled on + untrusted networks, where such identification data should not be made available. Use this + option to permit other systems to identify on which interfaces they are connected to this + system. The three special values control propagation of the LLDP packets. The + nearest-bridge setting permits propagation only to the nearest connected + bridge, non-tpmr-bridge permits propagation across Two-Port MAC Relays, + but not any other bridges, and customer-bridge permits propagation until + a customer bridge is reached. For details about these concepts, see + IEEE 802.1AB-2016. + Note that configuring this setting to true is equivalent to + nearest-bridge, the recommended and most restricted level of propagation. + See LLDP= above for an option to enable LLDP reception. + + + + + BindCarrier= + + A link name or a list of link names. When set, controls the behavior of the current + link. When all links in the list are in an operational down state, the current link is + brought down. When at least one link has carrier, the current interface is brought up. + + This forces ActivationPolicy= to be set to bound. + + + + + + Address= + + A static IPv4 or IPv6 address and its prefix length, separated by a + / character. Specify this key more than once to configure several + addresses. The format of the address must be as described in + inet_pton3. + This is a short-hand for an [Address] section only containing an Address key (see below). + This option may be specified more than once. + + If the specified address is 0.0.0.0 (for IPv4) or + :: (for IPv6), a new address range of the requested size is automatically + allocated from a system-wide pool of unused ranges. Note that the prefix length must be equal + or larger than 8 for IPv4, and 64 for IPv6. The allocated range is checked against all + current network interfaces and all known network configuration files to avoid address range + conflicts. The default system-wide pool consists of 192.168.0.0/16, 172.16.0.0/12 and + 10.0.0.0/8 for IPv4, and fd00::/8 for IPv6. This functionality is useful to manage a large + number of dynamically created network interfaces with the same network configuration and + automatic address range assignment. + + + + + Gateway= + + The gateway address, which must be in the format described in + inet_pton3. + This is a short-hand for a [Route] section only containing a Gateway= key. + This option may be specified more than once. + + + + + DNS= + + A DNS server address, which must be in the format described in + inet_pton3. + This option may be specified more than once. Each address can optionally take a port number + separated with :, a network interface name or index separated with + %, and a Server Name Indication (SNI) separated with #. + When IPv6 address is specified with a port number, then the address must be in the square + brackets. That is, the acceptable full formats are + 111.222.333.444:9953%ifname#example.com for IPv4 and + [1111:2222::3333]:9953%ifname#example.com for IPv6. If an empty string is + assigned, then the all previous assignments are cleared. This setting is read by + systemd-resolved.service8. + + + + + + Domains= + + A whitespace-separated list of domains which should be resolved using the DNS servers + on this link. Each item in the list should be a domain name, optionally prefixed with a tilde + (~). The domains with the prefix are called "routing-only domains". The + domains without the prefix are called "search domains" and are first used as search suffixes + for extending single-label hostnames (hostnames containing no dots) to become fully qualified + domain names (FQDNs). If a single-label hostname is resolved on this interface, each of the + specified search domains are appended to it in turn, converting it into a fully qualified + domain name, until one of them may be successfully resolved. + + Both "search" and "routing-only" domains are used for routing of DNS queries: look-ups + for hostnames ending in those domains (hence also single label names, if any "search domains" + are listed), are routed to the DNS servers configured for this interface. The domain routing + logic is particularly useful on multi-homed hosts with DNS servers serving particular private + DNS zones on each interface. + + The "routing-only" domain ~. (the tilde indicating definition of a + routing domain, the dot referring to the DNS root domain which is the implied suffix of all + valid DNS names) has special effect. It causes all DNS traffic which does not match another + configured domain routing entry to be routed to DNS servers specified for this interface. + This setting is useful to prefer a certain set of DNS servers if a link on which they are + connected is available. + + This setting is read by + systemd-resolved.service8. + "Search domains" correspond to the domain and search + entries in + resolv.conf5. + Domain name routing has no equivalent in the traditional glibc API, which has no concept of + domain name servers limited to a specific link. + + + + + DNSDefaultRoute= + + Takes a boolean argument. If true, this link's configured DNS servers are used for + resolving domain names that do not match any link's configured Domains= + setting. If false, this link's configured DNS servers are never used for such domains, and + are exclusively used for resolving names that match at least one of the domains configured on + this link. If not specified defaults to an automatic mode: queries not matching any link's + configured domains will be routed to this link if it has no routing-only domains configured. + + + + + + NTP= + + An NTP server address (either an IP address, or a hostname). This option may be + specified more than once. This setting is read by + systemd-timesyncd.service8. + + + + + + IPForward= + + Configures IP packet forwarding for the system. If enabled, incoming packets on any + network interface will be forwarded to any other interfaces according to the routing table. + Takes a boolean, or the values ipv4 or ipv6, which only + enable IP packet forwarding for the specified address family. This controls the + net.ipv4.ip_forward and net.ipv6.conf.all.forwarding + sysctl options of the network interface (see + ip-sysctl.txt + for details about sysctl options). Defaults to no. + + Note: this setting controls a global kernel option, and does so one way only: if a + network that has this setting enabled is set up the global setting is turned on. However, + it is never turned off again, even after all networks with this setting enabled are shut + down again. + + To allow IP packet forwarding only between specific network interfaces use a firewall. + + + + + + IPMasquerade= + + Configures IP masquerading for the network interface. If enabled, packets forwarded + from the network interface will be appear as coming from the local host. Takes one of + ipv4, ipv6, both, or no. Defaults to no. If enabled, this automatically sets IPForward= to one of ipv4, ipv6 or yes. Note. Any positive boolean values such as yes or true are now deprecated. Please use one of the values in the above. - - - - IPv6PrivacyExtensions= - Configures use of stateless temporary - addresses that change over time (see RFC 4941, - Privacy Extensions for Stateless Address Autoconfiguration - in IPv6). Takes a boolean or the special values - prefer-public and - kernel. When true, enables the privacy - extensions and prefers temporary addresses over public - addresses. When prefer-public, enables the - privacy extensions, but prefers public addresses over - temporary addresses. When false, the privacy extensions - remain disabled. When kernel, the kernel's - default setting will be left in place. Defaults to - no. - - - IPv6AcceptRA= - Takes a boolean. Controls IPv6 Router Advertisement (RA) reception support for the - interface. If true, RAs are accepted; if false, RAs are ignored. When RAs are accepted, they may - trigger the start of the DHCPv6 client if the relevant flags are set in the RA data, or if no - routers are found on the link. The default is to disable RA reception for bridge devices or when IP - forwarding is enabled, and to enable it otherwise. Cannot be enabled on bond devices and when link - local addressing is disabled. + + - Further settings for the IPv6 RA support may be configured in the [IPv6AcceptRA] section, see - below. + + IPv6PrivacyExtensions= + + Configures use of stateless temporary addresses that change over time (see + RFC 4941, + Privacy Extensions for Stateless Address Autoconfiguration in IPv6). Takes a boolean or the + special values prefer-public and kernel. When true, + enables the privacy extensions and prefers temporary addresses over public addresses. When + prefer-public, enables the privacy extensions, but prefers public + addresses over temporary addresses. When false, the privacy extensions remain disabled. When + kernel, the kernel's default setting will be left in place. Defaults to + no. + + - Also see ip-sysctl.txt in the kernel - documentation regarding accept_ra, but note that systemd's setting of - 1 (i.e. true) corresponds to kernel's setting of 2. + + IPv6AcceptRA= + + Takes a boolean. Controls IPv6 Router Advertisement (RA) reception support for the + interface. If true, RAs are accepted; if false, RAs are ignored. When RAs are accepted, they + may trigger the start of the DHCPv6 client if the relevant flags are set in the RA data, or + if no routers are found on the link. The default is to disable RA reception for bridge + devices or when IP forwarding is enabled, and to enable it otherwise. Cannot be enabled on + bond devices and when link local addressing is disabled. + + Further settings for the IPv6 RA support may be configured in the [IPv6AcceptRA] + section, see below. + + Also see + ip-sysctl.txt + in the kernel documentation regarding accept_ra, but note that systemd's + setting of 1 (i.e. true) corresponds to kernel's setting of + 2. Note that kernel's implementation of the IPv6 RA protocol is always disabled, regardless of this setting. If this option is enabled, a userspace implementation of the IPv6 RA protocol is used, and the kernel's own implementation remains disabled, since systemd-networkd needs to know all details supplied in the advertisements, - and these are not available from the kernel if the kernel's own implementation is used. + and these are not available from the kernel if the kernel's own implementation is used. + - - - IPv6DuplicateAddressDetection= - Configures the amount of IPv6 Duplicate - Address Detection (DAD) probes to send. When unset, the kernel's default will be used. - - - - IPv6HopLimit= - Configures IPv6 Hop Limit. For each router that - forwards the packet, the hop limit is decremented by 1. When the - hop limit field reaches zero, the packet is discarded. - When unset, the kernel's default will be used. - - - - IPv4AcceptLocal= - Takes a boolean. Accept packets with local source addresses. In combination - with suitable routing, this can be used to direct packets between two local interfaces over - the wire and have them accepted properly. When unset, the kernel's default will be used. - - - - IPv4RouteLocalnet= - Takes a boolean. When true, the kernel does not consider loopback addresses as martian source or destination - while routing. This enables the use of 127.0.0.0/8 for local routing purposes. When unset, the kernel's default will be used. - - - - IPv4ProxyARP= - Takes a boolean. Configures proxy ARP for IPv4. Proxy ARP is the technique in which one host, - usually a router, answers ARP requests intended for another machine. By "faking" its identity, - the router accepts responsibility for routing packets to the "real" destination. See RFC 1027. - When unset, the kernel's default will be used. - - - - IPv6ProxyNDP= - Takes a boolean. Configures proxy NDP for IPv6. Proxy NDP (Neighbor Discovery - Protocol) is a technique for IPv6 to allow routing of addresses to a different - destination when peers expect them to be present on a certain physical link. - In this case a router answers Neighbour Advertisement messages intended for - another machine by offering its own MAC address as destination. - Unlike proxy ARP for IPv4, it is not enabled globally, but will only send Neighbour - Advertisement messages for addresses in the IPv6 neighbor proxy table, - which can also be shown by ip -6 neighbour show proxy. - systemd-networkd will control the per-interface `proxy_ndp` switch for each configured - interface depending on this option. - When unset, the kernel's default will be used. - - - - IPv6ProxyNDPAddress= - An IPv6 address, for which Neighbour Advertisement messages will be - proxied. This option may be specified more than once. systemd-networkd will add the - entries to the kernel's IPv6 neighbor proxy table. - This option implies but has no effect if - has been set to false. When unset, the kernel's default will be used. - - - - IPv6SendRA= - Whether to enable or disable Router Advertisement sending on a link. Takes a - boolean value. When enabled, prefixes configured in [IPv6Prefix] sections and routes - configured in [IPv6RoutePrefix] sections are distributed as defined in the [IPv6SendRA] - section. If DHCPPrefixDelegation= is enabled, then the delegated prefixes - are also distributed. See DCHPPrefixDelegation= setting and the - [IPv6SendRA], [IPv6Prefix], [IPv6RoutePrefix], and [DHCPPrefixDelegation] sections for more - configuration options. - - - DHCPPrefixDelegation= - Takes a boolean value. When enabled, requests subnet prefixes acquired by a - DHCPv6 client, or by a DHCPv4 client through the 6RD option configured on another link. By - default, an address within each delegated prefix will be assigned, and the prefixes will be - announced through IPv6 Router Advertisement when IPv6SendRA= is enabled. - Such default settings can be configured in [DHCPPrefixDelegation] section. Defaults to - disabled. - - - IPv6MTUBytes= - Configures IPv6 maximum transmission unit (MTU). - An integer greater than or equal to 1280 bytes. When unset, the kernel's default will be used. - - - - KeepMaster= - - Takes a boolean value. When enabled, the current master interface index will not be - changed, and BatmanAdvanced=, Bond=, - Bridge=, and VRF= settings are ignored. This may be - useful when a netdev with a master interface is created by another program, e.g. - systemd-nspawn1. - Defaults to false. - - - - BatmanAdvanced= - Bond= - Bridge= - VRF= - - The name of the B.A.T.M.A.N. Advanced, bond, bridge, or VRF interface to add the link - to. See - systemd.netdev5. - - - - - IPoIB= - IPVLAN= - IPVTAP= - L2TP= - MACsec= - MACVLAN= - MACVTAP= - Tunnel= - VLAN= - VXLAN= - Xfrm= - - The name of an IPoIB, IPVLAN, IPVTAP, L2TP, MACsec, MACVLAN, MACVTAP, tunnel, VLAN, - VXLAN, or Xfrm to be created on the link. See - systemd.netdev5. - This option may be specified more than once. - - + + + + IPv6DuplicateAddressDetection= + + Configures the amount of IPv6 Duplicate Address Detection (DAD) probes to send. When + unset, the kernel's default will be used. + + + + + IPv6HopLimit= + + Configures IPv6 Hop Limit. For each router that forwards the packet, the hop limit is + decremented by 1. When the hop limit field reaches zero, the packet is discarded. When unset, + the kernel's default will be used. + + + + + IPv4AcceptLocal= + + Takes a boolean. Accept packets with local source addresses. In combination with + suitable routing, this can be used to direct packets between two local interfaces over the + wire and have them accepted properly. When unset, the kernel's default will be used. + + + + + IPv4RouteLocalnet= + + Takes a boolean. When true, the kernel does not consider loopback addresses as martian + source or destination while routing. This enables the use of 127.0.0.0/8 for local routing + purposes. When unset, the kernel's default will be used. + + + + + IPv4ProxyARP= + + Takes a boolean. Configures proxy ARP for IPv4. Proxy ARP is the technique in which one + host, usually a router, answers ARP requests intended for another machine. By "faking" its + identity, the router accepts responsibility for routing packets to the "real" destination. + See RFC 1027. When unset, the + kernel's default will be used. + + + + + IPv6ProxyNDP= + + Takes a boolean. Configures proxy NDP for IPv6. Proxy NDP (Neighbor Discovery Protocol) + is a technique for IPv6 to allow routing of addresses to a different destination when peers + expect them to be present on a certain physical link. In this case a router answers Neighbour + Advertisement messages intended for another machine by offering its own MAC address as + destination. Unlike proxy ARP for IPv4, it is not enabled globally, but will only send + Neighbour Advertisement messages for addresses in the IPv6 neighbor proxy table, which can + also be shown by ip -6 neighbour show proxy. systemd-networkd will control + the per-interface `proxy_ndp` switch for each configured interface depending on this option. + When unset, the kernel's default will be used. + + + + + IPv6ProxyNDPAddress= + + An IPv6 address, for which Neighbour Advertisement messages will be proxied. This + option may be specified more than once. systemd-networkd will add the + IPv6ProxyNDPAddress= entries to the kernel's IPv6 neighbor proxy table. + This setting implies IPv6ProxyNDP=yes but has no effect if + IPv6ProxyNDP= has been set to false. When unset, the kernel's default will + be used. + + + + + IPv6SendRA= + + Whether to enable or disable Router Advertisement sending on a link. Takes a boolean + value. When enabled, prefixes configured in [IPv6Prefix] sections and routes configured in + the [IPv6RoutePrefix] sections are distributed as defined in the [IPv6SendRA] section. If + DHCPPrefixDelegation= is enabled, then the delegated prefixes are also + distributed. See DCHPPrefixDelegation= setting and the [IPv6SendRA], + [IPv6Prefix], [IPv6RoutePrefix], and [DHCPPrefixDelegation] sections for more configuration + options. + + + + + DHCPPrefixDelegation= + + Takes a boolean value. When enabled, requests subnet prefixes acquired by a DHCPv6 + client, or by a DHCPv4 client through the 6RD option configured on another link. By default, + an address within each delegated prefix will be assigned, and the prefixes will be announced + through IPv6 Router Advertisement when IPv6SendRA= is enabled. Such + default settings can be configured in the [DHCPPrefixDelegation] section. Defaults to + disabled. + + + + + IPv6MTUBytes= + + Configures IPv6 maximum transmission unit (MTU). An integer greater than or equal to + 1280 bytes. When unset, the kernel's default will be used. + + + + + KeepMaster= + + Takes a boolean value. When enabled, the current master interface index will not be + changed, and BatmanAdvanced=, Bond=, + Bridge=, and VRF= settings are ignored. This may be + useful when a netdev with a master interface is created by another program, e.g. + systemd-nspawn1. + Defaults to false. + + + + + BatmanAdvanced= + Bond= + Bridge= + VRF= + + The name of the B.A.T.M.A.N. Advanced, bond, bridge, or VRF interface to add the link + to. See + systemd.netdev5. + + + + + + IPoIB= + IPVLAN= + IPVTAP= + L2TP= + MACsec= + MACVLAN= + MACVTAP= + Tunnel= + VLAN= + VXLAN= + Xfrm= + + The name of an IPoIB, IPVLAN, IPVTAP, L2TP, MACsec, MACVLAN, MACVTAP, tunnel, VLAN, + VXLAN, or Xfrm to be created on the link. See + systemd.netdev5. + This option may be specified more than once. + + + ActiveSlave= Takes a boolean. Specifies the new active slave. The ActiveSlave= - option is only valid for following modes: - active-backup, - balance-alb and - balance-tlb. Defaults to false. - + option is only valid for following modes: active-backup, + balance-alb, and balance-tlb. Defaults to false. + PrimarySlave= - Takes a boolean. Specifies which slave is the primary device. The specified - device will always be the active slave while it is available. Only when the - primary is off-line will alternate devices be used. This is useful when - one slave is preferred over another, e.g. when one slave has higher throughput - than another. The PrimarySlave= option is only valid for - following modes: - active-backup, - balance-alb and - balance-tlb. Defaults to false. - + Takes a boolean. Specifies which slave is the primary device. The specified device will + always be the active slave while it is available. Only when the primary is off-line will + alternate devices be used. This is useful when one slave is preferred over another, e.g. + when one slave has higher throughput than another. The PrimarySlave= + option is only valid for following modes: active-backup, + balance-alb, and balance-tlb. Defaults to false. + ConfigureWithoutCarrier= - Takes a boolean. Allows networkd to configure a specific link even if it has no carrier. - Defaults to false. If enabled, and the IgnoreCarrierLoss= setting is not - explicitly set, then it is enabled as well. - + Takes a boolean. Allows networkd to configure a specific link even if it has no + carrier. Defaults to false. If enabled, and the IgnoreCarrierLoss= setting + is not explicitly set, then it is enabled as well. + IgnoreCarrierLoss= @@ -967,6 +1018,7 @@ Table=1234 + KeepConfiguration= @@ -989,1140 +1041,1210 @@ Table=1234 [Address] Section Options - An [Address] section accepts the following keys. Specify several [Address] - sections to configure several addresses. + An [Address] section accepts the following keys. Specify several [Address] sections to + configure several addresses. - - - Address= - - As in the [Network] section. This key is mandatory. Each [Address] section can contain one - Address= setting. - - - - Peer= - - The peer address in a point-to-point connection. - Accepts the same format as the Address= - key. - - - - Broadcast= - - Takes an IPv4 address or boolean value. The address must be in the format described in - inet_pton3. - If set to true, then the IPv4 broadcast address will be derived from the - Address= setting. If set to false, then the broadcast address will not - be set. Defaults to true, except for wireguard interfaces, where it default to false. - - - - - Label= - - Specifies the label for the IPv4 address. The label must be a 7-bit ASCII string with - a length of 1…15 characters. Defaults to unset. - - - - PreferredLifetime= - - Allows the default "preferred lifetime" of the address to be overridden. Only three - settings are accepted: forever, infinity, which is the - default and means that the address never expires, and 0, which means that the - address is considered immediately "expired" and will not be used, unless explicitly requested. A - setting of is useful for addresses which are added to be - used only by a specific application, which is then configured to use them explicitly. - - - - Scope= - - The scope of the address, which can be - global (valid everywhere on the network, even through a gateway), - link (only valid on this device, will not traverse a gateway) or - host (only valid within the device itself, e.g. 127.0.0.1) - or an unsigned integer in the range 0…255. - Defaults to global. - - - - RouteMetric= - - The metric of the prefix route, which is pointing to the subnet of the configured IP - address, taking the configured prefix length into account. Takes an unsigned integer in the - range 0…4294967295. When unset or set to 0, the kernel's default value is used. This - setting will be ignored when AddPrefixRoute= is false. - - - - HomeAddress= - - Takes a boolean. Designates this address the "home address" as defined in - RFC 6275. - Supported only on IPv6. Defaults to false. - - - - DuplicateAddressDetection= - - Takes one of ipv4, ipv6, - both, none. When ipv4, - performs IPv4 Address Conflict Detection. See - RFC 5227. - When ipv6, performs IPv6 Duplicate Address Detection. See - RFC 4862. - Defaults to ipv6. - - - - ManageTemporaryAddress= - - Takes a boolean. If true the kernel manage temporary addresses created - from this one as template on behalf of Privacy Extensions - RFC 3041. For this to become - active, the use_tempaddr sysctl setting has to be set to a value greater than zero. - The given address needs to have a prefix length of 64. This flag allows using privacy - extensions in a manually configured network, just like if stateless auto-configuration - was active. Defaults to false. - - - - AddPrefixRoute= - - Takes a boolean. When true, the prefix route for the address is automatically added. - Defaults to true. - - - - AutoJoin= - - Takes a boolean. Joining multicast group on ethernet level via - ip maddr command would not work if we have an Ethernet switch that does - IGMP snooping since the switch would not replicate multicast packets on ports that did not - have IGMP reports for the multicast addresses. Linux vxlan interfaces created via - ip link add vxlan or networkd's netdev kind vxlan have the group option - that enables then to do the required join. By extending ip address command with option - autojoin we can get similar functionality for openvswitch (OVS) vxlan - interfaces as well as other tunneling mechanisms that need to receive multicast traffic. - Defaults to no. - - - + + + Address= + + As in the [Network] section. This setting is mandatory. Each [Address] section can + contain one Address= setting. + + + + + Peer= + + The peer address in a point-to-point connection. Accepts the same format as the + Address= setting. + + + + + Broadcast= + + Takes an IPv4 address or boolean value. The address must be in the format described in + inet_pton3. + If set to true, then the IPv4 broadcast address will be derived from the + Address= setting. If set to false, then the broadcast address will not be + set. Defaults to true, except for wireguard interfaces, where it default to false. + + + + + Label= + + Specifies the label for the IPv4 address. The label must be a 7-bit ASCII string with + a length of 1…15 characters. Defaults to unset. + + + + + PreferredLifetime= + + Allows the default "preferred lifetime" of the address to be overridden. Only three + settings are accepted: forever, infinity, which is the + default and means that the address never expires, and 0, which means that + the address is considered immediately "expired" and will not be used, unless explicitly + requested. A setting of is useful for addresses which + are added to be used only by a specific application, which is then configured to use them + explicitly. + + + + + Scope= + + The scope of the address, which can be global (valid everywhere on + the network, even through a gateway), link (only valid on this device, + will not traverse a gateway) or host (only valid within the device itself, + e.g. 127.0.0.1) or an integer in the range 0…255. Defaults to global. + + + + + + RouteMetric= + + The metric of the prefix route, which is pointing to the subnet of the configured IP + address, taking the configured prefix length into account. Takes an unsigned integer in the + range 0…4294967295. When unset or set to 0, the kernel's default value is used. This + setting will be ignored when AddPrefixRoute= is false. + + + + + HomeAddress= + + Takes a boolean. Designates this address the "home address" as defined in + RFC 6275. Supported only on IPv6. + Defaults to false. + + + + + DuplicateAddressDetection= + + Takes one of ipv4, ipv6, both, + or none. When ipv4, performs IPv4 Address Conflict + Detection. See RFC 5227. + When ipv6, performs IPv6 Duplicate Address Detection. See + RFC 4862. Defaults to + ipv6. + + + + + ManageTemporaryAddress= + + Takes a boolean. If true the kernel manage temporary addresses created from this one as + template on behalf of Privacy Extensions + RFC 3041. For this to become active, + the use_tempaddr sysctl setting has to be set to a value greater than zero. The given address + needs to have a prefix length of 64. This flag allows using privacy extensions in a manually + configured network, just like if stateless auto-configuration was active. Defaults to false. + + + + + + AddPrefixRoute= + + Takes a boolean. When true, the prefix route for the address is automatically added. + Defaults to true. + + + + + AutoJoin= + + Takes a boolean. Joining multicast group on ethernet level via + ip maddr command would not work if we have an Ethernet switch that does + IGMP snooping since the switch would not replicate multicast packets on ports that did not + have IGMP reports for the multicast addresses. Linux vxlan interfaces created via + ip link add vxlan or networkd's netdev kind vxlan have the group option + that enables then to do the required join. By extending ip address command with option + autojoin we can get similar functionality for openvswitch (OVS) vxlan + interfaces as well as other tunneling mechanisms that need to receive multicast traffic. + Defaults to no. + + + [Neighbor] Section Options - A [Neighbor] section accepts the following keys. The neighbor section adds a permanent, static - entry to the neighbor table (IPv6) or ARP table (IPv4) for the given hardware address on the links - matched for the network. Specify several [Neighbor] sections to configure several static neighbors. - - - - Address= - - The IP address of the neighbor. - - - - LinkLayerAddress= - - The link layer address (MAC address or IP address) of the neighbor. - - - + A [Neighbor] section accepts the following keys. The neighbor section adds a permanent, + static entry to the neighbor table (IPv6) or ARP table (IPv4) for the given hardware address on the + links matched for the network. Specify several [Neighbor] sections to configure several static + neighbors. + + + + Address= + + The IP address of the neighbor. + + + + + LinkLayerAddress= + + The link layer address (MAC address or IP address) of the neighbor. + + + - + [IPv6AddressLabel] Section Options - An [IPv6AddressLabel] section accepts the following keys. Specify several [IPv6AddressLabel] - sections to configure several address labels. IPv6 address labels are used for address selection. See - RFC 3484. Precedence is managed by userspace, - and only the label itself is stored in the kernel. + An [IPv6AddressLabel] section accepts the following keys. Specify several [IPv6AddressLabel] + sections to configure several address labels. IPv6 address labels are used for address selection. + See RFC 3484. Precedence is managed by + userspace, and only the label itself is stored in the kernel. - - - Label= - - The label for the prefix, an unsigned integer in the range 0…4294967294. - 0xffffffff is reserved. This setting is mandatory. - - - - Prefix= - - IPv6 prefix is an address with a prefix length, separated by a slash / character. - This key is mandatory. - - - + + + Label= + + The label for the prefix, an unsigned integer in the range 0…4294967294. 0xffffffff is + reserved. This setting is mandatory. + + + + + Prefix= + + IPv6 prefix is an address with a prefix length, separated by a slash + / character. This setting is mandatory. + + + - + [RoutingPolicyRule] Section Options - An [RoutingPolicyRule] section accepts the following keys. Specify several [RoutingPolicyRule] - sections to configure several rules. + An [RoutingPolicyRule] section accepts the following settings. Specify several + [RoutingPolicyRule] sections to configure several rules. - - - TypeOfService= - - Takes a number between 0 and 255 that specifies the type of service to match. - - - - From= - - Specifies the source address prefix to match. Possibly followed by a slash and the prefix length. - - - - To= - - Specifies the destination address prefix to match. Possibly followed by a slash and the prefix length. - - - - FirewallMark= - - Specifies the iptables firewall mark value to match (a number between 1 and - 4294967295). Optionally, the firewall mask (also a number between 1 and 4294967295) can be - suffixed with a slash (/), e.g., 7/255. - - - - Table= - - Specifies the routing table identifier to lookup if the rule selector matches. Takes one of predefined names - default, main, and local, and names defined in RouteTable= - in networkd.conf5, - or a number between 1 and 4294967295. Defaults to main. - - - - Priority= - - Specifies the priority of this rule. Priority= is an unsigned - integer in the range 0…4294967295. Higher number means lower priority, and rules get - processed in order of increasing number. Defaults to unset, and the kernel will pick - a value dynamically. - - - - IncomingInterface= - - Specifies incoming device to match. If the interface is loopback, the rule only matches packets originating from this host. - - - - OutgoingInterface= - - Specifies the outgoing device to match. The outgoing interface is only available for packets originating from local sockets that are bound to a device. - - - - SourcePort= - - Specifies the source IP port or IP port range match in forwarding information base (FIB) rules. - A port range is specified by the lower and upper port separated by a dash. Defaults to unset. - - - - DestinationPort= - - Specifies the destination IP port or IP port range match in forwarding information base (FIB) rules. - A port range is specified by the lower and upper port separated by a dash. Defaults to unset. - - - - IPProtocol= - - Specifies the IP protocol to match in forwarding information base (FIB) rules. Takes IP protocol name such as tcp, - udp or sctp, or IP protocol number such as 6 for tcp or - 17 for udp. - Defaults to unset. - - - - InvertRule= - - A boolean. Specifies whether the rule is to be inverted. Defaults to false. - - - - Family= - - Takes a special value ipv4, ipv6, or - both. By default, the address family is determined by the address - specified in To= or From=. If neither - To= nor From= are specified, then defaults to - ipv4. - - - - User= - - Takes a username, a user ID, or a range of user IDs separated by a dash. Defaults to - unset. - - - - SuppressPrefixLength= - - Takes a number N in the range 0…128 and rejects routing - decisions that have a prefix length of N or less. Defaults to - unset. - - - - SuppressInterfaceGroup= - - Takes an integer in the range 0…2147483647 and rejects routing decisions that have - an interface with the same group id. It has the same meaning as - in ip rule. Defaults to unset. - - - - Type= - - Specifies Routing Policy Database (RPDB) rule type. Takes one of blackhole, - unreachable or prohibit. - - - - - + + + TypeOfService= + + Takes a number between 0 and 255 that specifies the type of service to match. + + - - [NextHop] Section Options - The [NextHop] section is used to manipulate entries in the kernel's "nexthop" tables. The - [NextHop] section accepts the following keys. Specify several [NextHop] sections to configure several - hops. + + From= + + Specifies the source address prefix to match. Possibly followed by a slash and the + prefix length. + + - - - Id= - - The id of the next hop. Takes an unsigned integer in the range 1…4294967295. If left - unspecified, then automatically chosen by kernel. - - - - Gateway= - - As in the [Network] section. - - - - Family= - - Takes one of the special values ipv4 or ipv6. - By default, the family is determined by the address specified in - Gateway=. If Gateway= is not specified, then defaults - to ipv4. - - - - OnLink= - - Takes a boolean. If set to true, the kernel does not have to check if the gateway is - reachable directly by the current machine (i.e., attached to the local network), so that we - can insert the nexthop in the kernel table without it being complained about. Defaults to - no. - - - - Blackhole= - - Takes a boolean. If enabled, packets to the corresponding routes are discarded - silently, and Gateway= cannot be specified. Defaults to - no. - - - - Group= - - Takes a whitespace separated list of nexthop IDs. Each ID must be in the range - 1…4294967295. Optionally, each nexthop ID can take a weight after a colon - (id:weight). - The weight must be in the range 1…255. If the weight is not specified, then it is assumed - that the weight is 1. This setting cannot be specified with Gateway=, - Family=, Blackhole=. This setting can be specified - multiple times. If an empty string is assigned, then the all previous assignments are - cleared. Defaults to unset. - - - + + To= + + Specifies the destination address prefix to match. Possibly followed by a slash and the + prefix length. + + + + + FirewallMark= + + Specifies the iptables firewall mark value to match (a number in the range + 1…4294967295). Optionally, the firewall mask (also a number between 1…4294967295) can be + suffixed with a slash (/), e.g., 7/255. + + + + + Table= + + Specifies the routing table identifier to lookup if the rule selector matches. Takes + one of predefined names default, main, and + local, and names defined in RouteTable= in + networkd.conf5, + or a number between 1 and 4294967295. Defaults to main. + + + + + Priority= + + Specifies the priority of this rule. Priority= is an integer in the + range 0…4294967295. Higher number means lower priority, and rules get processed in order of + increasing number. Defaults to unset, and the kernel will pick a value dynamically. + + + + + IncomingInterface= + + Specifies incoming device to match. If the interface is loopback, the rule only matches + packets originating from this host. + + + + + OutgoingInterface= + + Specifies the outgoing device to match. The outgoing interface is only available for + packets originating from local sockets that are bound to a device. + + + + + SourcePort= + + Specifies the source IP port or IP port range match in forwarding information base + (FIB) rules. A port range is specified by the lower and upper port separated by a dash. + Defaults to unset. + + + + + DestinationPort= + + Specifies the destination IP port or IP port range match in forwarding information base + (FIB) rules. A port range is specified by the lower and upper port separated by a dash. + Defaults to unset. + + + + + IPProtocol= + + Specifies the IP protocol to match in forwarding information base (FIB) rules. Takes IP + protocol name such as tcp, udp or + sctp, or IP protocol number such as 6 for + tcp or 17 for udp. Defaults to unset. + + + + + + InvertRule= + + A boolean. Specifies whether the rule is to be inverted. Defaults to false. + + + + + Family= + + Takes a special value ipv4, ipv6, or + both. By default, the address family is determined by the address + specified in To= or From=. If neither + To= nor From= are specified, then defaults to + ipv4. + + + + + User= + + Takes a username, a user ID, or a range of user IDs separated by a dash. Defaults to + unset. + + + + + SuppressPrefixLength= + + Takes a number N in the range 0…128 and rejects routing + decisions that have a prefix length of N or less. Defaults to + unset. + + + + + SuppressInterfaceGroup= + + Takes an integer in the range 0…2147483647 and rejects routing decisions that have + an interface with the same group id. It has the same meaning as + in ip rule. Defaults to unset. + + + + + Type= + + Specifies Routing Policy Database (RPDB) rule type. Takes one of + blackhole, unreachable or prohibit. + + + + + + + + [NextHop] Section Options + + The [NextHop] section is used to manipulate entries in the kernel's "nexthop" tables. The + [NextHop] section accepts the following settings. Specify several [NextHop] sections to configure + several hops. + + + + Id= + + The id of the next hop. Takes an integer in the range 1…4294967295. If unspecified, + then automatically chosen by kernel. + + + + + Gateway= + + As in the [Network] section. + + + + + Family= + + Takes one of the special values ipv4 or ipv6. + By default, the family is determined by the address specified in + Gateway=. If Gateway= is not specified, then defaults + to ipv4. + + + + + OnLink= + + Takes a boolean. If set to true, the kernel does not have to check if the gateway is + reachable directly by the current machine (i.e., attached to the local network), so that we + can insert the nexthop in the kernel table without it being complained about. Defaults to + no. + + + + + Blackhole= + + Takes a boolean. If enabled, packets to the corresponding routes are discarded + silently, and Gateway= cannot be specified. Defaults to + no. + + + + + Group= + + Takes a whitespace separated list of nexthop IDs. Each ID must be in the range + 1…4294967295. Optionally, each nexthop ID can take a weight after a colon + (id:weight). + The weight must be in the range 1…255. If the weight is not specified, then it is assumed + that the weight is 1. This setting cannot be specified with Gateway=, + Family=, Blackhole=. This setting can be specified + multiple times. If an empty string is assigned, then the all previous assignments are + cleared. Defaults to unset. + + + [Route] Section Options - The [Route] section accepts the following keys. Specify several [Route] sections to configure - several routes. - - - Gateway= - - Takes the gateway address or the special values _dhcp4 and - _ipv6ra. If _dhcp4 or _ipv6ra is - set, then the gateway address provided by DHCPv4 or IPv6 RA is used. - - - - GatewayOnLink= - - Takes a boolean. If set to true, the kernel does not have to check if the gateway is - reachable directly by the current machine (i.e., attached to the local network), so that we - can insert the route in the kernel table without it being complained about. Defaults to - no. - - - - Destination= - - The destination prefix of the route. Possibly - followed by a slash and the prefix length. If omitted, a - full-length host route is assumed. - - - - Source= - - The source prefix of the route. Possibly followed by - a slash and the prefix length. If omitted, a full-length - host route is assumed. - - - - Metric= - - The metric of the route. Takes an unsigned integer in the range 0…4294967295. - Defaults to unset, and the kernel's default will be used. - - - - IPv6Preference= - - Specifies the route preference as defined in RFC 4191 for Router Discovery messages. Which - can be one of low the route has a lowest priority, medium - the route has a default priority or high the route has a highest priority. - - - - - Scope= - - The scope of the IPv4 route, which can be global, site, - link, host, or - nowhere: - - global means the route can reach - hosts more than one hop away. + The [Route] section accepts the following settings. Specify several [Route] sections to + configure several routes. - site means an interior route in - the local autonomous system. + + + Gateway= + + Takes the gateway address or the special values _dhcp4 and + _ipv6ra. If _dhcp4 or _ipv6ra is + set, then the gateway address provided by DHCPv4 or IPv6 RA is used. + + - link means the route can only - reach hosts on the local network (one hop away). + + GatewayOnLink= + + Takes a boolean. If set to true, the kernel does not have to check if the gateway is + reachable directly by the current machine (i.e., attached to the local network), so that we + can insert the route in the kernel table without it being complained about. Defaults to + no. + + - host means the route will not - leave the local machine (used for internal addresses like - 127.0.0.1). + + Destination= + + The destination prefix of the route. Possibly followed by a slash and the prefix + length. If omitted, a full-length host route is assumed. + + - nowhere means the destination - doesn't exist. - - For IPv4 route, defaults to host if Type= is - local or nat, - and link if Type= is - broadcast, multicast, or anycast. - In other cases, defaults to global. The value is - not used for IPv6. - - - - PreferredSource= - - The preferred source address of the route. The address - must be in the format described in - inet_pton3. - - - - Table= - - The table identifier for the route. Takes one of predefined names default, main, - and local, and names defined in RouteTable= in networkd.conf - 5, or a number between 1 and 4294967295. The table can be retrieved using - ip route show table num. If unset and Type= is local, - broadcast, anycast, or nat, then local is used. - In other cases, defaults to main. + + Source= + + The source prefix of the route. Possibly followed by a slash and the prefix length. If + omitted, a full-length host route is assumed. + + + + + Metric= + + The metric of the route. Takes an unsigned integer in the range 0…4294967295. Defaults + to unset, and the kernel's default will be used. + + + + + IPv6Preference= + + Specifies the route preference as defined in + RFC 4191 for Router Discovery + messages. Which can be one of low the route has a lowest priority, + medium the route has a default priority or high the + route has a highest priority. + + + + + Scope= + + The scope of the IPv4 route, which can be global, + site, link, host, or + nowhere: + + + global means the route can reach hosts more than one hop away. + + + + + site means an interior route in the local autonomous system. + + + + + link means the route can only reach hosts on the local network + (one hop away). + + + + host means the route will not leave the local machine (used for + internal addresses like 127.0.0.1). + + + + nowhere means the destination doesn't exist. + + + + For IPv4 route, defaults to host if Type= is + local or nat, and link if + Type= is broadcast, multicast, or + anycast. In other cases, defaults to global. The value + is not used for IPv6. + + + + + PreferredSource= + + The preferred source address of the route. The address must be in the format described + in + inet_pton3. - - - - Protocol= - - The protocol identifier for the route. Takes a number between 0 and 255 or the special values - kernel, boot, static, - ra and dhcp. Defaults to static. - - - - - Type= - - Specifies the type for the route. Takes one of unicast, - local, broadcast, anycast, - multicast, blackhole, unreachable, - prohibit, throw, nat, and - xresolve. If unicast, a regular route is defined, i.e. a - route indicating the path to take to a destination network address. If blackhole, packets - to the defined route are discarded silently. If unreachable, packets to the defined route - are discarded and the ICMP message "Host Unreachable" is generated. If prohibit, packets - to the defined route are discarded and the ICMP message "Communication Administratively Prohibited" is - generated. If throw, route lookup in the current routing table will fail and the route - selection process will return to Routing Policy Database (RPDB). Defaults to unicast. - - - - - InitialCongestionWindow= - - The TCP initial congestion window is used during the start of a TCP connection. - During the start of a TCP session, when a client requests a resource, the server's initial - congestion window determines how many packets will be sent during the initial burst of data - without waiting for acknowledgement. Takes a number between 1 and 1023. Note that 100 is - considered an extremely large value for this option. When unset, the kernel's default - (typically 10) will be used. - - - - InitialAdvertisedReceiveWindow= - - The TCP initial advertised receive window is the amount of receive data (in bytes) - that can initially be buffered at one time on a connection. The sending host can send only - that amount of data before waiting for an acknowledgment and window update from the - receiving host. Takes a number between 1 and 1023. Note that 100 is considered an extremely - large value for this option. When unset, the kernel's default will be used. - - - - QuickAck= - - Takes a boolean. When true enables TCP quick ack mode for the route. When unset, the kernel's default will be used. - - - - - FastOpenNoCookie= - - Takes a boolean. When true enables TCP fastopen without a cookie on a per-route basis. - When unset, the kernel's default will be used. - - - - - TTLPropagate= - - Takes a boolean. When true enables TTL propagation at Label Switched Path (LSP) egress. - When unset, the kernel's default will be used. - - - - + + + + + Table= + + The table identifier for the route. Takes one of predefined names + default, main, and local, and names + defined in RouteTable= in + networkd.conf5, + or a number between 1 and 4294967295. The table can be retrieved using + ip route show table num. If unset and + Type= is local, broadcast, + anycast, or nat, then local is used. + In other cases, defaults to main. + + + + + Protocol= + + The protocol identifier for the route. Takes a number between 0 and 255 or the special + values kernel, boot, static, + ra and dhcp. Defaults to static. + + + + + + Type= + + Specifies the type for the route. Takes one of unicast, + local, broadcast, anycast, + multicast, blackhole, unreachable, + prohibit, throw, nat, and + xresolve. If unicast, a regular route is defined, i.e. + a route indicating the path to take to a destination network address. If + blackhole, packets to the defined route are discarded silently. If + unreachable, packets to the defined route are discarded and the ICMP + message "Host Unreachable" is generated. If prohibit, packets to the + defined route are discarded and the ICMP message "Communication Administratively Prohibited" + is generated. If throw, route lookup in the current routing table will + fail and the route selection process will return to Routing Policy Database (RPDB). Defaults + to unicast. + + + + + InitialCongestionWindow= + + The TCP initial congestion window is used during the start of a TCP connection. + During the start of a TCP session, when a client requests a resource, the server's initial + congestion window determines how many packets will be sent during the initial burst of data + without waiting for acknowledgement. Takes a number between 1 and 1023. Note that 100 is + considered an extremely large value for this option. When unset, the kernel's default + (typically 10) will be used. + + + + + InitialAdvertisedReceiveWindow= + + The TCP initial advertised receive window is the amount of receive data (in bytes) + that can initially be buffered at one time on a connection. The sending host can send only + that amount of data before waiting for an acknowledgment and window update from the + receiving host. Takes a number between 1 and 1023. Note that 100 is considered an extremely + large value for this option. When unset, the kernel's default will be used. + + + + + QuickAck= + + Takes a boolean. When true enables TCP quick ack mode for the route. When unset, the + kernel's default will be used. + + + + + FastOpenNoCookie= + + Takes a boolean. When true enables TCP fastopen without a cookie on a per-route basis. + When unset, the kernel's default will be used. + + + + + TTLPropagate= + + Takes a boolean. When true enables TTL propagation at Label Switched Path (LSP) egress. + When unset, the kernel's default will be used. + + + + MTUBytes= - The maximum transmission unit in bytes to set for the - route. The usual suffixes K, M, G, are supported and are - understood to the base of 1024. - Note that if IPv6 is enabled on the interface, and the MTU is chosen - below 1280 (the minimum MTU for IPv6) it will automatically be increased to this value. + The maximum transmission unit in bytes to set for the route. The usual suffixes K, M, + G, are supported and are understood to the base of 1024. - - - IPServiceType= - - Takes one of the special values none, CS6, or - CS4. When none no IP service type is set to the packet - sent from the DHCPv4 client. When CS6 (network control) or - CS4 (realtime), the corresponding service type will be set. Defaults to - CS6. - - - - TCPAdvertisedMaximumSegmentSize= - - Specifies the Path MSS (in bytes) hints given on TCP layer. The usual suffixes K, M, G, are - supported and are understood to the base of 1024. An unsigned integer in the range 1…4294967294. - When unset, the kernel's default will be used. - - - - MultiPathRoute=address[@name] [weight] - - Configures multipath route. Multipath routing is the technique of using multiple - alternative paths through a network. Takes gateway address. Optionally, takes a network - interface name or index separated with @, and a weight in 1..256 for - this multipath route separated with whitespace. This setting can be specified multiple - times. If an empty string is assigned, then the all previous assignments are cleared. - - - - NextHop= - - Specifies the nexthop id. Takes an unsigned integer in the range 1…4294967295. - If set, the corresponding [NextHop] section must be configured. Defaults to unset. - - - + + + + TCPAdvertisedMaximumSegmentSize= + + Specifies the Path MSS (in bytes) hints given on TCP layer. The usual suffixes K, M, G, + are supported and are understood to the base of 1024. An unsigned integer in the range + 1…4294967294. When unset, the kernel's default will be used. + + + + + MultiPathRoute=address[@name] [weight] + + Configures multipath route. Multipath routing is the technique of using multiple + alternative paths through a network. Takes gateway address. Optionally, takes a network + interface name or index separated with @, and a weight in 1..256 for this + multipath route separated with whitespace. This setting can be specified multiple times. If + an empty string is assigned, then the all previous assignments are cleared. + + + + + NextHop= + + Specifies the nexthop id. Takes an unsigned integer in the range 1…4294967295. If set, + the corresponding [NextHop] section must be configured. Defaults to unset. + + + [DHCPv4] Section Options - The [DHCPv4] section configures the DHCPv4 client, if it is enabled with the - DHCP= setting described above: - + The [DHCPv4] section configures the DHCPv4 client, if it is enabled with the + DHCP= setting described above: - + - - SendHostname= - - When true (the default), the machine's hostname (or the value specified with - Hostname=, described below) will be sent to the DHCP server. Note that the - hostname must consist only of 7-bit ASCII lower-case characters and no spaces or dots, and be - formatted as a valid DNS domain name. Otherwise, the hostname is not sent even if this option is - true. - - + - - Hostname= - - Use this value for the hostname which is sent to the DHCP server, instead of machine's hostname. - Note that the specified hostname must consist only of 7-bit ASCII lower-case characters and - no spaces or dots, and be formatted as a valid DNS domain name. - - + + SendHostname= + + When true (the default), the machine's hostname (or the value specified with + Hostname=, described below) will be sent to the DHCP server. Note that the + hostname must consist only of 7-bit ASCII lower-case characters and no spaces or dots, and be + formatted as a valid DNS domain name. Otherwise, the hostname is not sent even if this option + is true. + + - - MUDURL= - - When configured, the specified Manufacturer Usage Description (MUD) URL will be sent to the - DHCPv4 server. Takes a URL of length up to 255 characters. A superficial verification that the - string is a valid URL will be performed. DHCPv4 clients are intended to have at most one MUD URL - associated with them. See RFC 8520. - + + Hostname= + + Use this value for the hostname which is sent to the DHCP server, instead of machine's + hostname. Note that the specified hostname must consist only of 7-bit ASCII lower-case + characters and no spaces or dots, and be formatted as a valid DNS domain name. + + - MUD is an embedded software standard defined by the IETF that allows IoT device makers to - advertise device specifications, including the intended communication patterns for their device - when it connects to the network. The network can then use this to author a context-specific - access policy, so the device functions only within those parameters. - - + + MUDURL= + + When configured, the specified Manufacturer Usage Description (MUD) URL will be sent + to the DHCPv4 server. Takes a URL of length up to 255 characters. A superficial verification + that the string is a valid URL will be performed. DHCPv4 clients are intended to have at most + one MUD URL associated with them. See + RFC 8520. - - ClientIdentifier= - - The DHCPv4 client identifier to use. Takes one of , - or . If set to , the - MAC address of the link is used. If set to , an RFC4361-compliant Client - ID, which is the combination of IAID and DUID (see below), is used. If set to - , only DUID is used, this may not be RFC compliant, but some setups - may require to use this. Defaults to . - - + MUD is an embedded software standard defined by the IETF that allows IoT device makers + to advertise device specifications, including the intended communication patterns for their + device when it connects to the network. The network can then use this to author a + context-specific access policy, so the device functions only within those parameters. + + - - VendorClassIdentifier= - - The vendor class identifier used to identify vendor - type and configuration. - - + + ClientIdentifier= + + The DHCPv4 client identifier to use. Takes one of , + or . If set to , the + MAC address of the link is used. If set to , an RFC4361-compliant Client + ID, which is the combination of IAID and DUID (see below), is used. If set to + , only DUID is used, this may not be RFC compliant, but some setups + may require to use this. Defaults to . + + - - UserClass= - - A DHCPv4 client can use UserClass option to identify the type or category of user or - applications it represents. The information contained in this option is a string that represents - the user class of which the client is a member. Each class sets an identifying string of - information to be used by the DHCP service to classify clients. Takes a whitespace-separated list - of strings. - - + + VendorClassIdentifier= + + The vendor class identifier used to identify vendor type and configuration. + + - - DUIDType= - - Override the global DUIDType= setting for this network. See - networkd.conf5 - for a description of possible values. - - + + UserClass= + + A DHCPv4 client can use UserClass option to identify the type or category of user or + applications it represents. The information contained in this option is a string that + represents the user class of which the client is a member. Each class sets an identifying + string of information to be used by the DHCP service to classify clients. Takes a + whitespace-separated list of strings. + + - - DUIDRawData= - - Override the global DUIDRawData= setting for this network. See - networkd.conf5 - for a description of possible values. - - + + DUIDType= + + Override the global DUIDType= setting for this network. See + networkd.conf5 + for a description of possible values. + + - - IAID= - - The DHCP Identity Association Identifier (IAID) for the interface, a 32-bit unsigned - integer. - - + + DUIDRawData= + + Override the global DUIDRawData= setting for this network. See + networkd.conf5 + for a description of possible values. + + - - Anonymize= - - Takes a boolean. When true, the options sent to the DHCP server will follow the - RFC 7844 (Anonymity Profiles for - DHCP Clients) to minimize disclosure of identifying information. Defaults to false. + + IAID= + + The DHCP Identity Association Identifier (IAID) for the interface, a 32-bit unsigned + integer. + + - This option should only be set to true when MACAddressPolicy= is - set to (see - systemd.link5). - + + Anonymize= + + Takes a boolean. When true, the options sent to the DHCP server will follow the + RFC 7844 (Anonymity Profiles for + DHCP Clients) to minimize disclosure of identifying information. Defaults to false. - When true, SendHostname=, ClientIdentifier=, - VendorClassIdentifier=, UserClass=, - RequestOptions=, SendOption=, - SendVendorOption=, and MUDURL= are ignored. + This option should only be set to true when MACAddressPolicy= is set + to (see + systemd.link5). + - With this option enabled DHCP requests will mimic those generated by Microsoft - Windows, in order to reduce the ability to fingerprint and recognize installations. This - means DHCP request sizes will grow and lease data will be more comprehensive than normally, - though most of the requested data is not actually used. - - + When true, SendHostname=, ClientIdentifier=, + VendorClassIdentifier=, UserClass=, + RequestOptions=, SendOption=, + SendVendorOption=, and MUDURL= are ignored. - - RequestOptions= - - Sets request options to be sent to the server in the DHCPv4 request options list. A - whitespace-separated list of integers in the range 1…254. Defaults to unset. - - + With this option enabled DHCP requests will mimic those generated by Microsoft + Windows, in order to reduce the ability to fingerprint and recognize installations. This + means DHCP request sizes will grow and lease data will be more comprehensive than normally, + though most of the requested data is not actually used. + + - - SendOption= - - Send an arbitrary raw option in the DHCPv4 request. Takes a DHCP option number, data type - and data separated with a colon - (option:type:value). - The option number must be an integer in the range 1…254. The type takes one of - uint8, uint16, uint32, - ipv4address, or string. Special characters in the data - string may be escaped using C-style - escapes. This setting can be specified multiple times. If an empty string is specified, - then all options specified earlier are cleared. Defaults to unset. - - + + RequestOptions= + + Sets request options to be sent to the server in the DHCPv4 request options list. A + whitespace-separated list of integers in the range 1…254. Defaults to unset. + + - - SendVendorOption= - - Send an arbitrary vendor option in the DHCPv4 request. Takes a DHCP option number, data - type and data separated with a colon - (option:type:value). - The option number must be an integer in the range 1…254. The type takes one of - uint8, uint16, uint32, - ipv4address, or string. Special characters in the data - string may be escaped using C-style - escapes. This setting can be specified multiple times. If an empty string is specified, - then all options specified earlier are cleared. Defaults to unset. - - + + SendOption= + + Send an arbitrary raw option in the DHCPv4 request. Takes a DHCP option number, data + type and data separated with a colon + (option:type:value). + The option number must be an integer in the range 1…254. The type takes one of + uint8, uint16, uint32, + ipv4address, or string. Special characters in the data + string may be escaped using + C-style + escapes. This setting can be specified multiple times. If an empty string is + specified, then all options specified earlier are cleared. Defaults to unset. + + - + + SendVendorOption= + + Send an arbitrary vendor option in the DHCPv4 request. Takes a DHCP option number, data + type and data separated with a colon + (option:type:value). + The option number must be an integer in the range 1…254. The type takes one of + uint8, uint16, uint32, + ipv4address, or string. Special characters in the data + string may be escaped using + C-style + escapes. This setting can be specified multiple times. If an empty string is specified, + then all options specified earlier are cleared. Defaults to unset. + + - - Label= - - Specifies the label for the IPv4 address received from the DHCP server. - The label must be a 7-bit ASCII string with a length of 1…15 characters. - Defaults to unset. - - + + IPServiceType= + + Takes one of the special values none, CS6, or + CS4. When none no IP service type is set to the packet + sent from the DHCPv4 client. When CS6 (network control) or + CS4 (realtime), the corresponding service type will be set. Defaults to + CS6. + + - - UseDNS= - - When true (the default), the DNS servers received from the DHCP server will be used. + - This corresponds to the - option in resolv.conf5. - - + + Label= + + Specifies the label for the IPv4 address received from the DHCP server. The label must + be a 7-bit ASCII string with a length of 1…15 characters. Defaults to unset. + + - - RoutesToDNS= - - When true, the routes to the DNS servers received from the DHCP server will be - configured. When UseDNS= is disabled, this setting is ignored. - Defaults to true. - - + + UseDNS= + + When true (the default), the DNS servers received from the DHCP server will be used. + - - UseNTP= - - When true (the default), the NTP servers received from the DHCP server will be used by - systemd-timesyncd.service. - - + This corresponds to the option in + resolv.conf5. + + + - - RoutesToNTP= - - When true, the routes to the NTP servers received from the DHCP server will be - configured. When UseNTP= is disabled, this setting is ignored. - Defaults to true. - - + + RoutesToDNS= + + When true, the routes to the DNS servers received from the DHCP server will be + configured. When UseDNS= is disabled, this setting is ignored. Defaults to + true. + + - - UseSIP= - - When true (the default), the SIP servers received from the DHCP server will be collected - and made available to client programs. - - + + UseNTP= + + When true (the default), the NTP servers received from the DHCP server will be used by + systemd-timesyncd.service. + + - - UseMTU= - - When true, the interface maximum transmission unit from the DHCP server will be used on the - current link. If MTUBytes= is set, then this setting is ignored. Defaults to - false. - Note, some drivers will reset the interfaces if the MTU is changed. For such - interfaces, please try to use IgnoreCarrierLoss= with a short timespan, - e.g. 3 seconds. - - + + RoutesToNTP= + + When true, the routes to the NTP servers received from the DHCP server will be + configured. When UseNTP= is disabled, this setting is ignored. Defaults to + true. + + - - UseHostname= - - When true (the default), the hostname received from the DHCP server will be set as the - transient hostname of the system. - - + + UseSIP= + + When true (the default), the SIP servers received from the DHCP server will be collected + and made available to client programs. + + - - UseDomains= - - Takes a boolean, or the special value . When true, the domain name - received from the DHCP server will be used as DNS search domain over this link, similar to the - effect of the setting. If set to , the domain - name received from the DHCP server will be used for routing DNS queries only, but not for - searching, similar to the effect of the setting when the argument is - prefixed with ~. Defaults to false. + + UseMTU= + + When true, the interface maximum transmission unit from the DHCP server will be used on + the current link. If MTUBytes= is set, then this setting is ignored. + Defaults to false. - It is recommended to enable this option only on trusted networks, as setting this affects - resolution of all hostnames, in particular of single-label names. It is generally safer to use - the supplied domain only as routing domain, rather than as search domain, in order to not have it - affect local resolution of single-label names. + Note, some drivers will reset the interfaces if the MTU is changed. For such + interfaces, please try to use IgnoreCarrierLoss= with a short timespan, + e.g. 3 seconds. + + - When set to true, this setting corresponds to the option in - resolv.conf5. - - - + + UseHostname= + + When true (the default), the hostname received from the DHCP server will be set as the + transient hostname of the system. + + - - UseRoutes= - - When true (the default), the static routes will be requested from the DHCP server and added - to the routing table with a metric of 1024, and a scope of , - or , depending on the route's destination and - gateway. If the destination is on the local host, e.g., 127.x.x.x, or the same as the link's own - address, the scope will be set to . Otherwise if the gateway is null (a - direct route), a scope will be used. For anything else, scope defaults to - . - - + + UseDomains= + + Takes a boolean, or the special value . When true, the domain + name received from the DHCP server will be used as DNS search domain over this link, similar + to the effect of the setting. If set to , the + domain name received from the DHCP server will be used for routing DNS queries only, but not + for searching, similar to the effect of the setting when the + argument is prefixed with ~. Defaults to false. - - RouteMetric= - - Set the routing metric for routes specified by the DHCP server (including the prefix - route added for the specified prefix). Takes an unsigned integer in the range 0…4294967295. - Defaults to 1024. - - + It is recommended to enable this option only on trusted networks, as setting this + affects resolution of all hostnames, in particular of single-label names. It is generally + safer to use the supplied domain only as routing domain, rather than as search domain, in + order to not have it affect local resolution of single-label names. - - RouteTable=num - - The table identifier for DHCP routes (a number between 1 and 4294967295, or 0 to unset). - The table can be retrieved using ip route show table num. - - When used in combination with VRF=, the - VRF's routing table is used when this parameter is not specified. - - - + When set to true, this setting corresponds to the option in + resolv.conf5. + + + - - RouteMTUBytes= - - Specifies the MTU for the DHCP routes. Please see the [Route] section for further details. - - + + UseRoutes= + + When true (the default), the static routes will be requested from the DHCP server and + added to the routing table with a metric of 1024, and a scope of , + or , depending on the route's destination and + gateway. If the destination is on the local host, e.g., 127.x.x.x, or the same as the link's + own address, the scope will be set to . Otherwise if the gateway is null + (a direct route), a scope will be used. For anything else, scope + defaults to . + + - - UseGateway= - - When true, the gateway will be requested from the DHCP server and added to the routing - table with a metric of 1024, and a scope of . When unset, the value specified - with UseRoutes= is used. - - + + RouteMetric= + + Set the routing metric for routes specified by the DHCP server (including the prefix + route added for the specified prefix). Takes an unsigned integer in the range 0…4294967295. + Defaults to 1024. + + - - UseTimezone= - When true, the timezone received from the DHCP server will be set as timezone of - the local system. Defaults to false. - + + RouteTable=num + + The table identifier for DHCP routes (a number between 1 and 4294967295, or 0 to + unset). The table can be retrieved using + ip route show table num. - - Use6RD= - When true, subnets of the received IPv6 prefix are assigned to downstream - interfaces which enables DHCPPrefixDelegation=. See also + When used in combination with VRF=, the VRF's routing table is + used when this parameter is not specified. + + + + + RouteMTUBytes= + + Specifies the MTU for the DHCP routes. Please see the [Route] section for further + details. + + + + + UseGateway= + + When true, the gateway will be requested from the DHCP server and added to the routing + table with a metric of 1024, and a scope of . When unset, the value + specified with UseRoutes= is used. + + + + + UseTimezone= + When true, the timezone received from the DHCP server will be set as timezone + of the local system. Defaults to false. + + + + Use6RD= + + When true, subnets of the received IPv6 prefix are assigned to downstream interfaces + which enables DHCPPrefixDelegation=. See also DHCPPrefixDelegation= in the [Network] section, the [DHCPPrefixDelegation] section, and RFC 5969. Defaults to - false. - + false. + + - - FallbackLeaseLifetimeSec= - - Allows to set DHCPv4 lease lifetime when DHCPv4 server does not send the lease lifetime. - Takes one of forever or infinity. The latter means that the - address never expires. Defaults to unset. - - + + FallbackLeaseLifetimeSec= + + Allows to set DHCPv4 lease lifetime when DHCPv4 server does not send the lease + lifetime. Takes one of forever or infinity. If + specified, the acquired address never expires. Defaults to unset. + + - + - - RequestBroadcast= - - Request the server to use broadcast messages before the IP address has been configured. - This is necessary for devices that cannot receive RAW packets, or that cannot receive packets at - all before an IP address has been configured. On the other hand, this must not be enabled on - networks where broadcasts are filtered out. - - + + RequestBroadcast= + + Request the server to use broadcast messages before the IP address has been configured. + This is necessary for devices that cannot receive RAW packets, or that cannot receive packets + at all before an IP address has been configured. On the other hand, this must not be enabled + on networks where broadcasts are filtered out. + + - - MaxAttempts= - - Specifies how many times the DHCPv4 client configuration should be attempted. Takes a - number or infinity. Defaults to infinity. Note that the - time between retries is increased exponentially, up to approximately one per minute, so the - network will not be overloaded even if this number is high. The default is suitable in most - circumstances. - - + + MaxAttempts= + + Specifies how many times the DHCPv4 client configuration should be attempted. Takes a + number or infinity. Defaults to infinity. Note that the + time between retries is increased exponentially, up to approximately one per minute, so the + network will not be overloaded even if this number is high. The default is suitable in most + circumstances. + + - - ListenPort= - - Set the port from which the DHCP client packets originate. - - + + ListenPort= + + Set the port from which the DHCP client packets originate. + + - - DenyList= - - A whitespace-separated list of IPv4 addresses. Each address can optionally take a - prefix length after /. DHCP offers from servers in the list are - rejected. Note that if AllowList= is configured then - DenyList= is ignored. - - + + DenyList= + + A whitespace-separated list of IPv4 addresses. Each address can optionally take a + prefix length after /. DHCP offers from servers in the list are rejected. + Note that if AllowList= is configured then DenyList= is + ignored. + + - - AllowList= - - A whitespace-separated list of IPv4 addresses. Each address can optionally take a - prefix length after /. DHCP offers from servers in the list are - accepted. - - + + AllowList= + + A whitespace-separated list of IPv4 addresses. Each address can optionally take a + prefix length after /. DHCP offers from servers in the list are accepted. + + + - - SendRelease= - - When true, the DHCPv4 client sends a DHCP release packet when it stops. Defaults to - true. - - + + SendRelease= + + When true, the DHCPv4 client sends a DHCP release packet when it stops. Defaults to + true. + + - - SendDecline= - - A boolean. When true, the DHCPv4 client receives the IP address from the - DHCP server. After a new IP is received, the DHCPv4 client performs IPv4 Duplicate Address - Detection. If duplicate use is detected, the DHCPv4 client rejects the IP by sending a - DHCPDECLINE packet and tries to obtain an IP address again. See RFC 5227. Defaults to - unset. - - - - - + + SendDecline= + + A boolean. When true, systemd-networkd performs IPv4 Duplicate + Address Detection to the acquired address by the DHCPv4 client. If duplicate is detected, + the DHCPv4 client rejects the address by sending a DHCPDECLINE packet to + the DHCP server, and tries to obtain an IP address again. See + RFC 5227. Defaults to false. + + + + [DHCPv6] Section Options - The [DHCPv6] section configures the DHCPv6 client, if it is enabled with the - DHCP= setting described above, or invoked by the IPv6 Router Advertisement: - + The [DHCPv6] section configures the DHCPv6 client, if it is enabled with the + DHCP= setting described above, or invoked by the IPv6 Router Advertisement: + - + - - MUDURL= - IAID= - DUIDType= - DUIDRawData= - RequestOptions= - - As in the [DHCPv4] section. - - + - - SendOption= - - As in the [DHCPv4] section, however because DHCPv6 uses 16-bit fields to store option - numbers, the option number is an integer in the range 1…65536. - - + + MUDURL= + IAID= + DUIDType= + DUIDRawData= + RequestOptions= + + As in the [DHCPv4] section. + + - - SendVendorOption= - - Send an arbitrary vendor option in the DHCPv6 request. Takes an enterprise identifier, DHCP - option number, data type, and data separated with a colon (enterprise - identifier:option:type:value). - Enterprise identifier is an unsigned integer in the range 1…4294967294. The option number must be - an integer in the range 1…254. Data type takes one of uint8, - uint16, uint32, ipv4address, - ipv6address, or string. Special characters in the data - string may be escaped using C-style - escapes. This setting can be specified multiple times. If an empty string is specified, - then all options specified earlier are cleared. Defaults to unset. - - + + SendOption= + + As in the [DHCPv4] section, however because DHCPv6 uses 16-bit fields to store option + numbers, the option number is an integer in the range 1…65536. + + - - UserClass= - - A DHCPv6 client can use User Class option to identify the type or category of user or - applications it represents. The information contained in this option is a string that represents - the user class of which the client is a member. Each class sets an identifying string of - information to be used by the DHCP service to classify clients. Special characters in the data - string may be escaped using C-style - escapes. This setting can be specified multiple times. If an empty string is specified, - then all options specified earlier are cleared. Takes a whitespace-separated list of - strings. Note that currently NUL bytes are not allowed. - - + + SendVendorOption= + + Send an arbitrary vendor option in the DHCPv6 request. Takes an enterprise identifier, + DHCP option number, data type, and data separated with a colon + (enterprise identifier:option:type:value). + Enterprise identifier is an unsigned integer in the range 1…4294967294. The option number + must be an integer in the range 1…254. Data type takes one of uint8, + uint16, uint32, ipv4address, + ipv6address, or string. Special characters in the data + string may be escaped using + C-style + escapes. This setting can be specified multiple times. If an empty string is + specified, then all options specified earlier are cleared. Defaults to unset. + + - - VendorClass= - - A DHCPv6 client can use VendorClass option to identify the vendor that manufactured the - hardware on which the client is running. The information contained in the data area of this - option is contained in one or more opaque fields that identify details of the hardware - configuration. Takes a whitespace-separated list of strings. - - + + UserClass= + + A DHCPv6 client can use User Class option to identify the type or category of user or + applications it represents. The information contained in this option is a string that + represents the user class of which the client is a member. Each class sets an identifying + string of information to be used by the DHCP service to classify clients. Special characters + in the data string may be escaped using + C-style + escapes. This setting can be specified multiple times. If an empty string is + specified, then all options specified earlier are cleared. Takes a whitespace-separated list + of strings. Note that currently NUL bytes are not allowed. + + - - PrefixDelegationHint= - - Takes an IPv6 address with prefix length in the same format as the - Address= in the [Network] section. The DHCPv6 client will include a prefix - hint in the DHCPv6 solicitation sent to the server. The prefix length must be in the range - 1…128. Defaults to unset. - - + + VendorClass= + + A DHCPv6 client can use VendorClass option to identify the vendor that manufactured the + hardware on which the client is running. The information contained in the data area of this + option is contained in one or more opaque fields that identify details of the hardware + configuration. Takes a whitespace-separated list of strings. + + - + + PrefixDelegationHint= + + Takes an IPv6 address with prefix length in the same format as the + Address= in the [Network] section. The DHCPv6 client will include a prefix + hint in the DHCPv6 solicitation sent to the server. The prefix length must be in the range + 1…128. Defaults to unset. + + - - UseAddress= - - When true (the default), the IP addresses provided by the DHCPv6 server will be - assigned. - - + - - UseDelegatedPrefix= - - When true (the default), the client will request the DHCPv6 server to delegate - prefixes. If the server provides prefixes to be delegated, then subnets of the prefixes are - assigned to the interfaces which enables DHCPPrefixDelegation=. - See also DHCPPrefixDelegation= in [Network] section, - [DHCPPrefixDelegation] section, and - RFC 8415. - - - + + UseAddress= + + When true (the default), the IP addresses provided by the DHCPv6 server will be + assigned. + + - - UseDNS= - UseNTP= - UseHostname= - UseDomains= - - As in the [DHCPv4] section. - - + + UseDelegatedPrefix= + + When true (the default), the client will request the DHCPv6 server to delegate + prefixes. If the server provides prefixes to be delegated, then subnets of the prefixes are + assigned to the interfaces which enables DHCPPrefixDelegation=. + See also the DHCPPrefixDelegation= setting in the [Network] section, + settings in the [DHCPPrefixDelegation] section, and + RFC 8415. + + + - + + UseDNS= + UseNTP= + UseHostname= + UseDomains= + + As in the [DHCPv4] section. + + - - WithoutRA= - - Allows DHCPv6 client to start without router advertisements's managed or other - address configuration flag. Takes one of no, solicit - or information-request. If this is not specified, - solicit is used when DHCPPrefixDelegation= is - enabled and UplinkInterface=:self is specified in the - [DHCPPrefixDelegation] section. Otherwise, defaults to no, and the - DHCPv6 client will be started when an RA is received. See also - DHCPv6Client= setting in the [IPv6AcceptRA] section. - - - + + + + WithoutRA= + + Allows DHCPv6 client to start without router advertisements's managed or other + address configuration flag. Takes one of no, solicit + or information-request. If this is not specified, + solicit is used when DHCPPrefixDelegation= is enabled + and UplinkInterface=:self is specified in the [DHCPPrefixDelegation] + section. Otherwise, defaults to no, and the DHCPv6 client will be started + when an RA is received. See also the DHCPv6Client= setting in the + [IPv6AcceptRA] section. + + +