EIGRP / OSPF dampening

Donn Lasher dlasher at clearskynet.net
Wed Dec 18 01:02:48 UTC 2002


I'm looking for a way to way to either dampen, penalize, or otherwise slow 
down a flapping interface, when the router has no "link state" information 
about the Layer 2 connection, which is itself causing the flap... Example...

Dec 17 08:23:50 xxx.xxx.xxx.xxx 2106: 15w5d: %DUAL-5-NBRCHANGE: IP-EIGRP 
10: Neighbor xxx.xxx.xxx.xxx (FastEthernet2/0.3) is down: peer restarted
Dec 17 08:23:52 xxx.xxx.xxx.xxx 2107: 15w5d: %DUAL-5-NBRCHANGE: IP-EIGRP 
10: Neighbor xxx.xxx.xxx.xxx (FastEthernet2/0.3) is up: new adjacency
Dec 17 08:24:09 xxx.xxx.xxx.xxx 2108: 15w5d: %DUAL-5-NBRCHANGE: IP-EIGRP 
10: Neighbor xxx.xxx.xxx.xxx (FastEthernet2/0.3) is down: peer restarted
Dec 17 08:24:11 xxx.xxx.xxx.xxx 2109: 15w5d: %DUAL-5-NBRCHANGE: IP-EIGRP 
10: Neighbor xxx.xxx.xxx.xxx (FastEthernet2/0.3) is up: new adjacency
Dec 17 08:24:42 xxx.xxx.xxx.xxx 2110: 15w5d: %DUAL-5-NBRCHANGE: IP-EIGRP 
10: Neighbor xxx.xxx.xxx.xxx (FastEthernet2/0.3) is down: peer restarted
Dec 17 08:24:43 xxx.xxx.xxx.xxx 2111: 15w5d: %DUAL-5-NBRCHANGE: IP-EIGRP 
10: Neighbor xxx.xxx.xxx.xxx (FastEthernet2/0.3) is up: new adjacency
Dec 17 08:25:18 xxx.xxx.xxx.xxx 2112: 15w5d: %DUAL-5-NBRCHANGE: IP-EIGRP 
10: Neighbor xxx.xxx.xxx.xxx (FastEthernet2/0.3) is down: peer restarted
Dec 17 08:25:20 xxx.xxx.xxx.xxx 2113: 15w5d: %DUAL-5-NBRCHANGE: IP-EIGRP 
10: Neighbor xxx.xxx.xxx.xxx (FastEthernet2/0.3) is up: new adjacency

This type of flapping yields an effectively down interface, yet, appears 
"up" so data gets blackholed while dead timers expire, etc.

I'm very familar with doing this via BGP, but haven't found any good way 
yet to do this with either EIGRP or OSPF.

Any ideas? Feel free to either reply to the list, or privately.

Thanks in advance..




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