> From: Thomas Schmid [mailto:[email protected]] > Sent: Thursday, August 02, 2018 12:12 PM > > Hi Adam, > > Am 02.08.2018 um 12:23 schrieb [email protected]: > > First thing first, > > To mitigate the damage due to RIB-FIB inconsistencies you could use the: > > "BGP-RIB Feedback Mechanism for Update Generation" > > "To configure BGP to wait for feedback from RIB indicating that the routes > that BGP installed in RIB are installed in FIB, before BGP sends out updates > to > neighbors, use the "update wait-install" command in router address-family > IPv4 or router address-family VPNv4 configuration mode." > > > > good point. Haven't heard of this from Cisco yet. Will discuss this with the > TAC. > > > > > Are you seeing any log messages indicating bottleneck between RIB and > FIB please? > > no. > > > Do you drop BGP updates on ingress with "as-path length ge 51" please? - > not only it's a good practice, but apparently long as-paths caused RIB-FIB > clogging in the past. > > > > On your note regarding the apparent relation to number of peers. > > So how long does it take for the process to complete for the 200 peers > nodes is it linearly proportional to the 20-30 minutes seen on 300 peers > nodes please?> Or the relation between number of peers and time follows > more of an exponential function (e.g. 290 all good and then 301 bang 30min) , > in which case that could also indicate something special with those "delta" > peers (e.g. some peers sending somewhat funky updates) (any slow peers > btw?) > > > > to be more clear: the full 700k BGP updates are only sent to a small fraction > of the e/iBGP peers (10-20). > > The BGP updates are sent out without delay to the neighbors. Wrt. the > number of sessions when things get bad, it's hard to tell since the number of > routers is 8 with 4 ASR9000 and 4 ASR9900 (many BGP peers). Within the 4 > ASR9900 it looks more or less linear. > Seems like the control plane is all good it's just the bcdlv2 having troubles - or GSP as the underlying transport. The " show bcdlv2 trace" should give TAC engineers tons of info. Btw if you do "show rib update-groups" you see no freeze counts right?
adam netconsultings.com ::carrier-class solutions for the telecommunications industry:: _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
