Server A has two interfaces (
i2) with the same IP on them, say fd11:1111:1111:1111::1/48.
Server B has the same two interfaces with the same IP on them, say fd11:1111:1111:1111::2/48.
When server B pings server A, the
echo request packets come from
i1 and the
echo reply packets are sent in
i2 (all this seen in wireshark), so
ping6 on server B never sees the replies.
How can one "force" the kernel to send the replies to the incoming interface? Is it even possible? Or a good idea?
If not, wouldn't it make sense to make
ping6 able to listen to all interfaces for replies? Or is there something bigger I'm missing?
FWIW this happens (only) when I use Bird2 with OSPF for routing as I thought you'd need something to take care of setting the routes, but if A prefers
i1 and B perfers
i2 then that doesn't help.
(Yes this comes from an XY problem and I'm already trying to fix X without this but I still want to know what should be done in such a case)
Edit: I can't find anything on this topic, that's why I think I may be missing something here