Is this a GSR?
--- On Tue, 22/7/08, Christian Koch <[EMAIL PROTECTED]> wrote: From: Christian Koch <[EMAIL PROTECTED]> Subject: Re: [c-nsp] BGP Hold Time Expired, but why? To: "Oliver Boehmer (oboehmer)" <[EMAIL PROTECTED]> Cc: "cisco-nsp" <[email protected]> Date: Tuesday, 22 July, 2008, 1:58 AM same issue, no differences...got me On Sun, Jul 20, 2008 at 2:53 AM, Oliver Boehmer (oboehmer) < [EMAIL PROTECTED]> wrote: > I don't know, but I would try it.. Looks weird.. > > oli > > ------------------------------ > *From:* Christian Koch [mailto:[EMAIL PROTECTED] > *Sent:* Saturday, July 19, 2008 7:07 PM > > *To:* Oliver Boehmer (oboehmer) > *Cc:* cisco-nsp > *Subject:* Re: [c-nsp] BGP Hold Time Expired, but why? > > config look ok as far as i can see, i actually dont have bgp router-id > set in the bgp config... you think if i add that with the loopback ip, it > would make a difference? > > > config > > router bgp 65000 > no synchronization > bgp log-neighbor-changes > bgp graceful-restart restart-time 120 > bgp graceful-restart stalepath-time 360 > bgp graceful-restart > bgp dampening > neighbor Backbone peer-group > neighbor Backbone remote-as 65000 > neighbor Backbone update-source Loopback1 > neighbor Backbone version 4 > neighbor Backbone send-community > neighbor 10.10.10.2 peer-group Backbone > neighbor 10.10.10.3 peer-group Backbone > no auto-summary > > > > > > On Sat, Jul 19, 2008 at 12:29 PM, Oliver Boehmer (oboehmer) < > [EMAIL PROTECTED]> wrote: > >> Hmm, "%BGP-5-ADJCHANGE: neighbor 10.10.10.3 Down BGP protocol >> initialization" looks unexpected, not sure what's happening.. >> just a hunch, but can you double-check your config regarding loopback >> addresses, bgp router-id and things? Possibly add some bgp debug (deb >> bgp all events, deb bgp all, deb bgp all keep) and see if something >> weird pops up? >> What does the neighbor's (10.10.10.3) log say? >> >> oli >> >> ________________________________ >> >> From: Christian Koch [mailto:[EMAIL PROTECTED] >> Sent: Saturday, July 19, 2008 3:08 PM >> To: Oliver Boehmer (oboehmer) >> Cc: cisco-nsp >> Subject: Re: [c-nsp] BGP Hold Time Expired, but why? >> >> >> hmm, i didnt check cef/mpls on the new path, i should try that.. there >> is connectivity between the loopbacks >> >> the session comes back up right after the timer expires.thats what >> puzzles me >> >> actually 3-4 is about how long i kept it down for.. >> >> >> Jul 16 14:29:22 EDT: %LINK-3-UPDOWN: Interface TenGigabitEthernet2/2, >> changed state to down >> Jul 16 14:29:22 EDT: %LINEPROTO-SP-5-UPDOWN: Line protocol on Interface >> TenGigabitEthernet2/2, changed state to down >> Jul 16 14:29:22 EDT: %OSPF-5-ADJCHG: Process 10, Nbr 10.10.10.2 on >> TenGigabitEthernet2/2 from FULL to DOWN, Neighbor Down: Interface down >> or detached >> Jul 16 14:29:22 EDT: %LDP-5-NBRCHG: LDP Neighbor 10.10.10.2:0 (11) is >> DOWN (Interface not operational) >> Jul 16 14:29:22 EDT: %LINK-SP-3-UPDOWN: Interface TenGigabitEthernet2/2, >> changed state to down >> Jul 16 14:29:23 EDT: %LINK-SP-3-UPDOWN: Interface TenGigabitEthernet2/2, >> changed state to up >> Jul 16 14:29:23 EDT: %LINK-3-UPDOWN: Interface TenGigabitEthernet2/2, >> changed state to up >> Jul 16 14:29:23 EDT: %LINEPROTO-5-UPDOWN: Line protocol on Interface >> TenGigabitEthernet2/2, changed state to up >> Jul 16 14:29:23 EDT: %LINEPROTO-SP-5-UPDOWN: Line protocol on Interface >> TenGigabitEthernet2/2, changed state to up >> Jul 16 14:29:33 EDT: %LDP-5-NBRCHG: LDP Neighbor 10.10.10.2:0 (11) is UP >> Jul 16 14:30:19 EDT: %OSPF-5-ADJCHG: Process 10, Nbr 10.10.10.2 on >> TenGigabitEthernet2/2 from LOADING to FULL, Loading Done >> Jul 16 14:30:37 EDT: %LDP-5-NBRCHG: LDP Neighbor 10.10.10.2:0 (4) is >> DOWN (Discovery Hello Hold Timer expired) >> Jul 16 14:31:39 EDT: %LDP-5-NBRCHG: LDP Neighbor 10.10.10.2:0 (4) is UP >> Jul 16 14:32:38 EDT: %BGP-3-NOTIFICATION: received from neighbor >> 10.10.10.3 4/0 (hold time expired) 0 bytes >> Jul 16 14:32:38 EDT: %BGP-5-ADJCHANGE: neighbor 10.10.10.3 Down BGP >> protocol initialization >> Jul 16 14:32:45 EDT: %BGP-5-ADJCHANGE: neighbor 10.10.10.3 Up >> >> >> >> On Sat, Jul 19, 2008 at 3:24 AM, Oliver Boehmer (oboehmer) >> <[EMAIL PROTECTED]> wrote: >> >> >> No clue what's happening.. I've seen issues in the past with TCP >> PMTUD >> when the path converges over a link with a different MTU (which >> is >> happening in your case), but as BGP will not send packets larger >> than >> 4k, this shouldn't be an issue here. >> >> How long did you take down the link before bringing it back up? >> I assume >> longer than 3 minutes? Have you checked CEF and MPLS along the >> new path? >> You have IP connectivity between the loopbacks aR1 and bR2? Does >> the >> session come back up eventually, or will it stay down? >> >> oli >> >> Christian Koch <> wrote on Saturday, July 19, 2008 8:38 AM: >> >> >> > sorry forgot to specify >> > >> > the bgp session from aR1 to bR2 is the session in question >> > >> > ck >> > >> > On Sat, Jul 19, 2008 at 2:21 AM, Christian Koch >> > <[EMAIL PROTECTED]> wrote: >> > >> >> Hello - >> >> >> >> I have the following topology in lab, testing different >> failure >> >> scenarios. When i disconnect the link between aR1 and bR1, >> what >> >> would appear to be normal happens - ospf and ldp neighbor go >> down. >> >> >> >> When i re-connect the link between aR1 and bR1, the interface >> comes >> >> back up, osfp/ldp neighbor is re-established. >> >> >> >> 3minutes later, bgp holdtime expires , and all links are up.. >> >> >> >> aR1-----------------bR1 >> >>> | >> >>> | >> >>> | >> >>> | aR2-----------------bR2 >> >> >> >> >> >> Some Notes >> >> - All Links 10GE >> >> - Full ibgp mesh >> >> - Peering is to loopbacks >> >> - OSPF as IGP >> >> - Loopbacks in OSPF >> >> - MPLS Enabled on Interfaces >> >> >> >> >> >> OSPF cost between aR1 and aR2 is 1 >> >> OSPF cost between bR1 and bR2 is 1 >> >> OSPF cost between aR1 and bR1 is 250 >> >> OSPF cost betwen aR2 and bR2 is 500 >> >> >> >> MTU 9216 between aR1 and aR2, aR1 and bR1, aR2 AND BR2 >> >> MTU 9182 between bR1 and bR2 >> >> >> >> >> >> IOS on aR1 and aR2 is 12.2.33.SRB2 - SUP720 >> >> IOS on bR1 and bR2 is 12.33.SRC - RSP720 >> >> >> >> >> >> i am stumped, any ideas would be helpful in trying to >> understand why >> >> the bgp session is going down due to expired hold time, when >> all >> >> links are up.. >> >> >> >> thanks! >> >> >> >> ck >> >> >> >> >> >> >> >> >> >> >> >> >> > >> > >> > -- >> > ^christian$ >> >> > _______________________________________________ >> > cisco-nsp mailing list [email protected] >> > https://puck.nether.net/mailman/listinfo/cisco-nsp >> > archive at http://puck.nether.net/pipermail/cisco-nsp/ >> >> >> >> >> >> -- >> ^christian$ >> > > _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/ __________________________________________________________ Not happy with your email address?. 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