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Strange RIP behavious

Hi all,

today I had a problem I cannot explain. I'm using Cisco 3550-48-SMI with IOS 12.1(22)EA1 as access switches for our customers. Each customer has a routed port on the 3550. The 3550 announces the connected and static routes via RIP to a couple of 7206 (my borders). The 7206 announce via RIP the default to the 3550. Everything works fine, but today all of sudden, a static route was marked as "possibly down", and my borders began to throw all traffic destined to that subnet to Null0 (as designed).

This is the relevant sanitized config:

interface FastEthernet0/35 description CustomerX PtP no switchport ip address 1.2.3.4 255.255.255.252 service-policy input 2mbit-in service-policy output 2mbit-out no cdp enable

router rip version 2 timers basic 3 10 0 10 redistribute connected redistribute static passive-interface default no passive-interface FastEthernet0/32 network 1.0.0.0 neighbor 1.2.2.3 neighbor 1.2.2.4 no auto-summary

ip route 1.6.7.8 255.255.255.240 1.2.3.5

Normaly a show ip rip database shows:

1.6.7.8/28 redistributed 1.2.3.4/30 directly connected, FastEthernet0/35

During the outage (that affected only this customer out of 40 on this

3550), it showed:

1.6.7.8/28 possibly down

1.2.3.4/30 directly connected, FastEthernet0/35

What strikes me is: how could it be possible to have a static selected as possibly down, when the connected route is (and has always be) up? I could ping the point to point fine from the router, no problems. The way to recover was simply to shut/unshut the relevant interface. Any hints what could be happened?

Reply to
Marco Matarazzo
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Marco, Your rip timers may be the issue. What are the timers set too on the

7200(s)?
Reply to
csouth

"csouth" wrote in comp.dcom.sys.cisco:

The timers are set to "timers basic 3 10 0 10" on all routers. I didn't mention this in my previuos post, as the issue happened on the same router that had the connected route and the static route. The borders were seeing the router possibly down because it was marked possibly down on the 3550, and what I was wondering why it was marked possibly down in the first place, given the fact that the connected interface never flapped...

Reply to
Marco Matarazzo

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