[Xorp-hackers] Question on RIB

Ben Greear greearb at candelatech.com
Wed Oct 24 17:03:51 PDT 2007

I have a scenario of 4 routers.  Starting config is:

A <-> B
B <-> C
C <-> D

B <-> D  (high cost link)

OSPF chooses the B-C link instead of the high cost link, and all is well.

Then, I disconnect (remove the interfaces & OSPF config for those interfaces
with xorpsh)

B & C

OSPF correctly starts using the high-cost link.

Then, I reconnect B & C with the low cost link.

It seems OSPF is trying to do the right thing.  Routes are deleted from
the high-cost link, but they do not appear on the low cost link.  The
reason appears to be this error in RIB.  I tried doing a 'commit' after
adding the interface and before adding the config to OSPF, but that did
not help.

Any idea how RIB learns about the directly connected interfaces?  Looks like
I need to somehow make it learn faster...

[ 2007/10/24 16:40:25 TRACE xorp_ospfv2 OSPF ] Add route Net Nexthop metric 2 equal false discard false policy
[ 2007/10/24 16:40:25  ERROR xorp_rib:17650 RIB rib.cc:856 add_route ] Attempting to add IGP route to table "ospf" (prefix next-hop no directly connected interface toward the next-hop router
[ 2007/10/24 16:40:25 WARNING xorp_rib XrlRibTarget ] Handling method for rib/0.1/add_route4 failed: XrlCmdError 102 Command failed Could not add IPv4 route net, nexthop: to unicast RIB
[ 2007/10/24 16:40:25  ERROR xorp_ospfv2:17680 OSPF xrl_io.cc:1167 route_command_done ] callback: add_route: ribname rib net nexthop 102 Command failed Could not add IPv4 route net, nexthop: to unicast RIB


Ben Greear <greearb at candelatech.com>
Candela Technologies Inc  http://www.candelatech.com

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