A MAC change can mean the link joined another network, e.g. on an
active-backup bond failover with FailOverMACPolicy=active. NDisc only
solicits when it starts, so IPv6 sat stale until the next unsolicited
RA. Restart NDisc to solicit immediately.
During early boot, interfaces may be renamed frequently, which can lead to
caching the driver name of a different interface. Invalidate the cached
driver whenever an interface rename is detected so it can be re-read using
the new name.
Follow-up for #42545.
Fixes#43099.
This adds an IPv4 counterpart to `IPv6ProxyNDPAddress=` for adding
manual entries to the kernel's IPv4 neighbour proxy table (check via
`ip -4 neighbour show proxy dev <dev>`). systemd-networkd only exposed
`IPv4ProxyARP=` for per-interface `proxy_arp` sysctl (automatic proxy
ARP) with no way to manage manual entries from a .network file.
To avoid duplicating the IPv6 proxy NDP code path, both families are
now combined into a single new `networkd-neighbor-proxy` module. The
IPv6 behaviour is preserved: `IPv6ProxyNDPAddress=` still implies
`IPv6ProxyNDP=yes` unless `IPv6ProxyNDP=` is explicitly disabled and
entries are still dropped if the kernel has no IPv6 support.
The same rule is applied to `IPv4ProxyARPAddress=`. It implies
`IPv4ProxyARP=yes` when the sysctl is not explicitly set and has no
effect if `IPv4ProxyARP=` has been set to false.
This keeps the user model symmetric and predictable across both
families: a single per-address setting that turns on the matching
per-interface sysctl automatically, while still letting system
administrators opt out by setting the boolean explicitly to false.
Note that the IPv4 manual NTF_PROXY entries installed here would
actually function without `proxy_arp` (unlike IPv6, where `proxy_ndp`
gates the manual entries); the implication is kept for symmetry with
`IPv6ProxyNDPAddress=` and is now called out explicitly in the man
page, together with the fact that enabling `proxy_arp` also activates
interface-wide automatic proxy ARP for routed-toward addresses on
connected subnets.
Parser-time validation rejects addresses the kernel would refuse:
the ANY/null address for both families, IPv4 and IPv6 multicast
and the IPv4 limited broadcast 255.255.255.255.
Signed-off-by: Aritra Basu <aritrbas+gh@cisco.com>
After enumeration, networkd may receive RTM_NEWLINK messages carrying a
stale interface name. This can happen when interface rename notifications
are queued before link enumeration and processed afterwards.
Previously, networkd could become confused by such a message and put the
corresponding Link into the failed state. Avoid this by checking whether
the new interface name is already in use by another interface and ignoring
the rename if so.
Fixes#20203.
E.g. on issue #20203, we may wrongly remove entry for another interface.
Let's mitigate issue on such situation for safety, though this does not
solve the issue.
This reverts commit 176b8be10f.
The check introduced by the commit is racy, as when format_ifname() is
called, the interface may be already renamed (again) to another name.
This is typically problematic when we swap interface names:
```
ip link set aaa name tmpname
ip link set bbb name aaa
ip link set tmpname bbb
```
When networkd received the notification about name change aaa -> tmpname,
the interface is already renamed from tmpname to bbb. So, the reverted
logic skips updating Link.ifname:
```
aaa: New interface name 'tmpname' received from the kernel does not correspond with the name currently configured on the actual interface 'bbb'. Ignoring.
```
On the second notification about name change bbb -> aaa, networkd fails to
update the mapping Manager.links_by_name, as we skipped previous renaming
and the mapping still has an outdated entry for 'aaa'.
```
bbb: Interface name change detected, renamed to aaa.
aaa: Failed to manage link by its new name: File exists
aaa: Could not process link message: File exists
aaa: Failed
aaa: State changed: configured -> failed
```
By reverting the commit, the issue is fixed. But the commit intended to
fix another issue #20203. So this reintroduces #20203. Let's fix it
in a later commit.
Fixes#42527.
Reintroduces #20203.
When the tracked IPv6 link-local address is removed, networkd clears
link->ipv6ll_address, but keeps DHCPv6, NDisc, and RADV running. These
engines keep using a stale source identity which affects the following:
- DHCPv6 client continues to send Solicit/Renew/Rebind from a nonexistent
source address.
- NDisc continues to send Router Solicitations from a nonexistent source
address. Router Advertisements cannot be received properly.
- RADV continues to advertise with a stale source address. This can lead
to downstream hosts configuring invalid routes.
- DHCP-PD prefixes remain configured without a valid upstream DHCPv6 path.
Added link_ipv6ll_lost() to stop IPv6 dynamic engines and related states:
- sd_dhcp6_client_stop()
- ndisc_stop() + ndisc_flush()
- sd_radv_stop()
This is called from address_drop() when the dropped address matches the
tracked IPv6LL. After clearing the tracked address, it scans for another
ready link-local address on the interface. If found, this is set as
link->ipv6ll_address and link_ipv6ll_gained() is called to restart the
engines with the new source identity.
This resolves the FIXME in address_drop().
Signed-off-by: Aritra Basu <aritrbas+gh@cisco.com>
Then, this deprecates
- BindToInterface=
- RelayTarget=
- RelayAgentCircuitId=
- RelayAgentRemoteId=
settings in [DHCPServer] section.
These are gracefully translated as new settings.
We have a number of *_unref_and_replace macros. One could think that
they are like the various free_and_replace variants, but they actually
create a new ref to the passed object. The free_and_replace variants
take ownership of the argument. This inconsistency is surprising. Rename
all those functions to have "_new_ref" at the end to make the difference
clear.
Add an sd_varlink* parameter to both functions so Varlink callers can
receive a deferred reply once all async work completes, symmetrically
with the existing sd_bus_message* path.
Co-developed-by: Claude Opus 4.6 <noreply@anthropic.com>
Let's synthesize DNS RRs for leases handed out by our DHCP server. This
way local VMs can have resolvable hostnames locally.
This does not implement reverse look ups for now. We can add this
later in similar fashion.
This renames and splits link_may_have_ipv6ll() into
link_ipv6ll_enabled_harder() and link_multicast_enabled(),
as they are completely irrelevant to each other.
Also, this makes link_ipv6ll_enabled_harder() work non-Wireguard
interfaces.
Previously, the property was checked only when an uevent is received,
so even if an interface has ID_NET_MANAGED_BY property, the interface
will be configured by networkd when reconfiguration is triggered e.g.
when interface state is changed.
Follow-up for ba87a61d05.
Fixes#36997.
If master ifindex is non-zero, then the carrier state and operational
state of the interface may be the enslaved state.
As the operational state is saved in link state file, and read by
wait-online, we need to update the state file when the master ifindex is
changed.
When an interface leaved from the master interface, then reading
IFLA_MASTER attribute causes ENODATA. When the interface was previously
enslaved to another interface, we need to remove reference to the
interface from the previous master interface.
This is especially important when
```
ip link set dev eth0 nomaster
```
is called.
Fixes a bug introduced by 0d411b7f8f (v249).
Fixes#37629.
Let's move some more implementation logic into functions. We keep
the logic that requires the macro in the macro and move the rest into
functions.
While we're at it, let's also make the parameter declarations of
all the string table macros less clausthrophobic.
Admittedly, some of our glyphs _are_ special, e.g. "O=" for SPECIAL_GLYPH_TOUCH ;)
But we don't need this in the name. The very long names make some invocations
very wordy, e.g. special_glyph(SPECIAL_GLYPH_SLIGHTLY_UNHAPPY_SMILEY).
Also, I want to add GLYPH_SPACE, which is not special at all.
In the kernel, all routing policy rules are not assigned to any interface,
and we can configure them even if the relevant interface is down state.
Fixes a regression caused by 4f8b153d90 (v257).
Fixes#36244.
By the previous commit, configuration source of addresses and routes are
saved on stop and restored on start. Hence, we can keep dynamic
configurations on stop.
Co-authored-by: Jian Zhang <zhangjian.3032@bytedance.com>
When an interface went down, IPv4 non-local routes are removed by the
kernel without any notifications. Let's forget the routes in that case.
Fixes#35047.
Previously, even if KeepConfiguration=dhcp or yes is specified in the
new .network file, dynamic configurations like DHCP address and routes
were dropped when 'networkctl reconfigure INTERFACE' is invoked.
If the setting is specified, let's gracefully handle the dynamic
configurations. Then, 'networkctl reconfigure' can be also used for
an interface that has critical connections.
r-vdp
Yu Watanabe
Aritra Basu
Daan De Meyer
Zbigniew Jędrzejewski-Szmek
Michael Vogt
noxiouz
Oleksandr AndrushchenkoandYu Watanabe
Lennart Poettering
Daan De Meyer
Jelle van der Waa
Zbigniew Jędrzejewski-Szmek
Mike Yuan
