On 2010-12-22, at 5:08 AM, Michael Robson wrote: <snip>
> If I configure BFD for each link and also attach it to OSPF and repeat the > experiment, the time to re-route is still 6-7 seconds. > > I can reason that this might work or that it shouldn't: does this not work > because there is no direct hook between BFD and LDP or should it work because > the pseudowire terminating loopbacks are advertised in OSPF, OSPF has been > hooked into BFD and ultimately the LFIB is built via the FIB and LIB (or > perhaps with this testbed because the size of the network and Penultimate Hop > Popping it means that the FIB is used anyway)? </snip> With regards to LDP, what about enabling mpls ldp session protection if you find that you really need it? (http://www.cisco.com/en/US/docs/ios/12_0s/feature/guide/fssespro.html) With regards to the OSPF/BFD integration, I'm not sure if it's the same for ISIS but I recently went through an exercise with BFD/ISIS integration where I was getting less than desirable results on a link failure while BFD tuned way down. Turned out that regardless of how quickly BFD reacted, I still had to tune down the ISIS timers to react more quickly when BFD detected a link failure. Now then, when I was testing this, I was using some pretty scary numbers, but ultimately got this to work in a lab, flawlessly. The result was that I went from 6-7 seconds worth of packet loss to zero seconds of packet loss between CEs when I yanked a link between two P/PE routers. Note that while I was able to achieve these results, I did so without ldp session protection enabled (I just recently read about it, but haven't had a chance to try it) and using L3VPNs, not EoMPLS. Also, this was done between 7301s, not 6500s, so YMMV on both counts: Here's what my end looked like: !R1 ! interface GigabitEthernet0/0 mpls ip bfd interval 50 min_rx 50 multiplier 3 isis bfd ! interface GigabitEthernet0/1 mpls ip bfd interval 50 min_rx 50 multiplier 3 isis bfd ! router isis spf-interval 5 1 50 prc-interval 5 1 50 lsp-gen-interval 5 1 50 ! !R2 ! interface GigabitEthernet0/0 mpls ip bfd interval 50 min_rx 50 multiplier 3 isis bfd ! interface GigabitEthernet0/1 mpls ip bfd interval 50 min_rx 50 multiplier 3 isis bfd ! router isis spf-interval 5 1 50 prc-interval 5 1 50 lsp-gen-interval 5 1 50 ! P.S. While digging through the archives for content, I also found this, which may be of more help to your particular configuration: ! router ospf 1 timers throttle spf 10 100 5000 timers throttle lsa all 10 100 5000 timers lsa arrival 80 ! _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
