Re: DVMRP routing loop

[Bjorn Carlsson <]

Well, I removed decnet from these boxes earlier tonight, maybe something got
screwed up then. I've been checking with tcpdump on stockholm.mbone.ebone.net
and can see no duplicates from 130.240.34.6 now atleast. 

stockholm# ./tcpdump -e -l -v -i le1 -n src host 130.240.34.6
tcpdump: listening on le1
20:23:17.954204 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 146: 130.240.34.6.33061 > 224.2.0.1.23457: udp 104 (ttl 186, id 38193)
20:23:21.468933 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 142: 130.240.34.6.33061 > 224.2.0.1.23457: udp 100 (ttl 186, id 38194)
20:23:24.314457 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 110: 130.240.34.6.33061 > 224.2.0.1.23457: udp 68 (ttl 186, id 38195)
20:23:28.965373 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 142: 130.240.34.6.33061 > 224.2.0.1.23457: udp 100 (ttl 186, id 38197)
20:23:34.428326 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 146: 130.240.34.6.33061 > 224.2.0.1.23457: udp 104 (ttl 186, id 38198)
20:23:38.508375 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 142: 130.240.34.6.33061 > 224.2.0.1.23457: udp 100 (ttl 186, id 38199)
20:23:45.321992 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 142: 130.240.34.6.33061 > 224.2.0.1.23457: udp 100 (ttl 186, id 38200)
20:23:49.478557 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 142: 130.240.34.6.33061 > 224.2.0.1.23457: udp 100 (ttl 186, id 38201)
20:23:52.179763 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 146: 130.240.34.6.33061 > 224.2.0.1.23457: udp 104 (ttl 186, id 38202)
20:23:58.348567 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 142: 130.240.34.6.33061 > 224.2.0.1.23457: udp 100 (ttl 186, id 38203)
20:24:05.229872 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 110: 130.240.34.6.33061 > 224.2.0.1.23457: udp 68 (ttl 186, id 38204)
20:24:10.217385 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 142: 130.240.34.6.33061 > 224.2.0.1.23457: udp 100 (ttl 186, id 38205)
20:24:17.343851 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 146: 130.240.34.6.33061 > 224.2.0.1.23457: udp 104 (ttl 186, id 38206)
20:24:23.646234 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 142: 130.240.34.6.33061 > 224.2.0.1.23457: udp 100 (ttl 186, id 38207)
20:24:26.677515 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 142: 130.240.34.6.33061 > 224.2.0.1.23457: udp 100 (ttl 186, id 38208)
20:24:31.827983 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 142: 130.240.34.6.33061 > 224.2.0.1.23457: udp 100 (ttl 186, id 38209)
20:24:38.607243 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 146: 130.240.34.6.33061 > 224.2.0.1.23457: udp 104 (ttl 186, id 38211)
20:24:42.006846 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 142: 130.240.34.6.33061 > 224.2.0.1.23457: udp 100 (ttl 186, id 38212)
20:24:49.165868 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 110: 130.240.34.6.33061 > 224.2.0.1.23457: udp 68 (ttl 186, id 38213)
20:24:53.445099 0:0:c:13:6e:6c 1:0:5e:2:0:1 0800 142: 130.240.34.6.33061 > 224.2.0.1.23457: udp 100 (ttl 186, id 38214)

--BC

> Speaking of duplicates, I'm seeing duplicate packets yet again between
> upper-gw and lower-gw.  This pair of routers seem to periodically get
> into a state where they create lots and lots of duplicates (in this
> particular case it's only 14 copies of each packet).
> 
>   Source        Response Dest    Overall     Packet Statistics For Traffic From
> 130.240.34.6    224.0.1.32       Packet      130.240.34.6 To 224.2.0.1
>      |       __/  rtt  416 ms     Rate       Lost/Sent = Pct  Rate
>      v      /     hop -204 s     -------     ---------------------
> ...
> 193.10.80.33    upper-gw.sunet.se 
>      |     ^      ttl   19        57 pps      -26/2    = --%   0 pps
>      v     |      hop  156 ms
> 193.10.80.34   
> 192.36.148.197  lower-gw.sunet.se 
> 
> Can someone please look into this?
> 
> Thanks,
>   Bill