Does radv protocol (re)scan interfaces on IPv6?

Alex Bligh alex at alex.org.uk
Tue Sep 2 21:22:11 CEST 2014


On 2 Sep 2014, at 12:52, Ondrej Zajicek <santiago at crfreenet.org> wrote:

> This should work. Could you check whether 'evrradv: Adding interface XXX'
> log message is logged if you enable debug messages for evrradv?

We've managed to find the cause of the problem, which is deeply strange.
We were disabling duplicate address detection after setting the link up.
If we move this to disabling DAD before setting the link up, the problem
does not arise. Note that this is just *detection* - it wasn't actually
discovering a duplicate address or anything.

I'll check the logs if this is still interesting.

> Also what you mean by 'add another interface'? The interface is created,
> or just bringed up?

We were
1. creating a new interface (a veth interface)
2. adding IP addresses,
3. then bringing the link up.

We were doing doing disabling DAD after step 3, but are now doing it
after step 2, which appears to eliminate the problem.

Not disabling DAD at all is also fine (save of course in the
situations where we need it disabled - VMware I'm looking at you).

> If the interface is also created, could you try to wait several seconds
> between the interface creation and activation?

I could try that for debugging purposes if you like, though we appear
to have fixed the problem for now. Why this fixes the problem is a
mystery!

> Are there any error messages in log?

Not that we noticed.

-- 
Alex Bligh




-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 842 bytes
Desc: Message signed with OpenPGP using GPGMail
URL: <http://trubka.network.cz/pipermail/bird-users/attachments/20140902/5de7dc60/attachment-0001.asc>


More information about the Bird-users mailing list