#1851 filter out ipv6 autoconfiguration from libnl messages
Opened 6 years ago by jhrozek. Modified 2 years ago

Currently, if an interface uses IPv6 autoconfiguration, we might receive updates for the existing prefix. From kernel's point of view, this is a change in configuration, too and the kernel emits a message. libnl-1.x does not filter it at all, while libnl-3.x does.

From a conversation I had with the libnl upstream maintainer:

13:44 <tgr> yeah, you may have received an update for that prefix that's all
13:44 <jhrozek> I see
13:44 <tgr> so the valid lifetime has been bumped but you can't really
see that from userspace
13:45 <tgr> nevertheless it's a change in the kernel's view of the
addressing table
13:46 <jhrozek> right, so there's no way to discard exactly this type
of message?
13:46 <tgr> are you only interested in changes to your own static addresses?
13:47 <tgr> you can check for IFA_F_PERMANENT
13:49 <jhrozek> basically I'm looking for a way to distinguish between
"this is a different address than we've had before" versus "update for a
prefix of an existing address"
13:49 <tgr> libnl3 can do that for you                 
13:49 <tgr> it compares the notification against the known address and
invokes a callback when there is a diff

Fields changed

milestone: NEEDS_TRIAGE => SSSD 1.13 beta
rhbz: => todo

Metadata Update from @jhrozek:
- Issue set to the milestone: SSSD Future releases (no date set yet)

2 years ago

Login to comment on this ticket.