On Thu, Mar 20, 2014 at 11:20:20AM +0200, Javor Kliachev wrote:
Hello,
Unfortunately, I still have no response from anybody. The messages continue to come into our logs. The iBGP session is UP since more than 1 week and till this moment we don't have complaints by some member.
Here is part of my bird.log: 07-03-2014 14:19:41 R0_29: Invalid NEXT_HOP attribute in route
This message means that BIRD tries to send a route with NEXT_HOP attribute X to a neighbor with IP address X. That happens because both iBGP and RS eBGP do not change NEXT_HOP, so if you have neighbor N connected to both: RS1 --- RS2 \ / \ / \ / N And it propagates the same route to both RS1 and RS2, then you have the same route both times in RS1 and RS2. Usually the directly received is prefered, but if for some reason the one received through IBGP is preferred (perhaps N sends a withdraw, which is propagated first to RS1 so directly received route disappears but the one received from RS2 by iBGP is still in RS1 for a moment), then it is scheduled for propagation back to N, but the check for NEXT_HOP denies it. I am not sure now whether this is some non-standard situation or the check should be silent. Generally i would advise against connecting route servers through IBGP. You get most routes two times, therefore double memory requirements. Another reason is that IBGP (unless with ADD-PATH extension) will silently eliminate non-preferred routes, which would cause hidden unexpected problems. -- Elen sila lumenn' omentielvo Ondrej 'SanTiago' Zajicek (email: santiago@crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."