We were told that 20ms is probably the lowest safe value you should run. For those reasons we're moving away from BFD and onto WanPhy and OTU2e encoding on the fibre. I remember testing the actual re-convergence time with BFD (on ASR9k) - with 20ms the actual re-convergence time (measured by a tester/traffic generator sending 1Gb/s stream over L2VPN) was always ~120ms. With WanPhy and OTU2e we could get around ~50ms. I suspect it has to do with the way error detection work in those technologies - it's threshold based, so once errors reach particular level switchover is triggered - whilst BFD has to actually lose those packets first.
kind regards Pshem On 3 April 2013 21:48, Adam Vitkovsky <[email protected]> wrote: >> on a cisco CRS what is the lowest / shortest BFD interval that can be set > It appears that on all XR platforms the lowest BFD interval is 15ms > unfortunately. > Combined with lowest multiplier of 2 it gives you 30ms detection time. We > use multiplier 3 which only leaves 5ms for the IPFRR to do its magic. > > > adam > > _______________________________________________ > cisco-nsp mailing list [email protected] > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
