A host can send Router Advertisements (RAs) without acting as a router.
In such cases, the lifetime of the RA header should be zero, but may
contain several options, and clients can configure addresses, routes,
and so on with the message. The host may (should?) send Neighbor
Announcements (NAs) without the router flag in that case.
So, when a NA without the router flag is received, let's not drop
configurations based on the previous RA options, but only drop the
default gateway configured based on the RA header.
See RFC 4861 Neighbor Discovery in IPv6, section 6.3.4:
https://www.rfc-editor.org/rfc/rfc4861#section-6.3.4:~:text=%2D%20The%20IsRouter%20flag,as%20a%20host.
> - The IsRouter flag in the cache entry MUST be set based on the Router
> flag in the received advertisement. In those cases where the IsRouter
> flag changes from TRUE to FALSE as a result of this update, the node
> MUST remove that router from the Default Router List and update the
> Destination Cache entries for all destinations using that neighbor as
> a router as specified in Section 7.3.3. This is needed to detect when
> a node that is used as a router stops forwarding packets due to being
> configured as a host.
Fixes a regression caused by 87a33c0740 (v256).
Fixes #37198.
System and Service Manager
Details
Most documentation is available on systemd's web site.
Assorted, older, general information about systemd can be found in the systemd Wiki.
Information about build requirements is provided in the README file.
Consult our NEWS file for information about what's new in the most recent systemd versions.
Please see the Code Map for information about this repository's layout and content.
Please see the Hacking guide for information on how to hack on systemd and test your modifications.
Please see our Contribution Guidelines for more information about filing GitHub Issues and posting GitHub Pull Requests.
When preparing patches for systemd, please follow our Coding Style Guidelines.
If you are looking for support, please contact our mailing list, join our IRC channel #systemd on libera.chat or Matrix channel
Stable branches with backported patches are available in the stable repo.
We have a security bug bounty program sponsored by the Sovereign Tech Fund hosted on YesWeHack
Repositories with distribution packages built from git main are available on OBS
