The RA's Retransmission Timer field was being ignored. This resolves the IPv6
Core Conformance test, v6LC.2.1.5 [1].
Retransmission Timer is a 32-bit unsigned integer. The time, in milliseconds,
between retransmitted Neighbor Solicitation messages. Used by the Address
Resolution and Neighbor Unreachability Detection (NUD) algorithm.
Support setting a default value for the neighbour retransmission timer value with:
[Network]
IPv6RetransmissionTimeSec=<int>
By default, upon receiving a Router Advertisement with the Retransmission Timer
field set to a non-zero value, it will update the kernel's retransmit timer value.
To disable this behaviour, configure the UseIPv6RetransmissionTime= under the
[IPv6AcceptRA] section.
[IPv6AcceptRA]
UseIPv6RetransmissionTime=<bool>
RFC4861: Neighbor Discovery in IPv6
* Section 4.2 RA Message Format.
* Section 6.3.4 Processing Received Router Advertisements
A Router Advertisement field (e.g., Cur Hop Limit, Reachable Time,
and Retrans Timer) may contain a value denoting that it is
unspecified. In such cases, the parameter should be ignored and the
host should continue using whatever value it is already using. In
particular, a host MUST NOT interpret the unspecified value as
meaning change back to the default value that was in use before the
first Router Advertisement was received.
The RetransTimer variable SHOULD be copied from the Retrans Timer
field, if the received value is non-zero.
References
[1] IPv6 Core Conformance Spec (PDF)
We have not tested if the settings actually filter DHCP servers.
Let's add a test case for the settings.
Note, the .network file used here has been unused since
0730e3767d. So, we can freely reuse it
without changing other test cases.
Closes#30107.
This reverts commits 89e73ce86f and
543d2a4d45.
The commit assign "custom" to fixed DUID type 5. When making DUID fully
configurable, the type number should be also configurable. Also, the
fully custom DUID should be acceptable for DHCPv4.
- rename TCPRetransmissionTimeOutSec= -> TCPRetransmissionTimeoutSec,
- refuse infinity,
- fix the input value verifier (USEC_PER_SEC -> USEC_PER_MSEC),
- use DIV_ROUND_UP() when assigning the value.
Follow-ups for 1412d4a4fe.
Closes#28898.
From `ip-link(8)`:
> [no]ignore-df - enables/disables IPv4 DF
suppression on this tunnel. Normally datagrams
that exceed the MTU will be fragmented; the
presence of the DF flag inhibits this, resulting
instead in an ICMP Unreachable (Fragmentation
Required) message. Enabling this attribute causes
the DF flag to be ignored.
If this option is enabled for a GRE/GRETAP tunnel, the `DF` flag in the outer IP header
will not inherit the inner IP header's `DF` flag.
This is useful to transfer packets that exceed the MTU of the underlay
network.
The commit 0f707207b9 enables strong
warning about missing prefix length in Address= setting.
The change was done in v241, and was about 4 years ago.
Let's drop the legacy assumption and make the parser consistent with
'ip address' command.
C.f. #11307.
Closes#26102.
Yu Watanabe
Matt Muggeridge
Nick Cao
Mike Yuan
Raito Bezarius
Zbigniew Jędrzejewski-Szmek
Luca Boccassi
Susant Sahani
Topi Miettinen
Frantisek Sumsal
Yuxiang Zhu
Dmitry V. Levin