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New Member

Router unreachable for 5 min

Hi has anyone run into the problem before

I have a router that becomes unreachable for about 5 mins it seems to happen once a week so far. When the router is unreachable I know it isn't a circuit issue as I see the circuit up, even had the carrier look at it when the router was unreachable and they didn't see anything wrong with the router. When I can get into it I've checked both interfaces, serial looks good but here is what I see on the ethernet:

Ethernet0/0 is up, line protocol is up

Hardware is AmdP2, address is 0008.21c9.4b60 (bia 0008.21c9.4b60)

Internet address is

MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec,

reliability 255/255, txload 1/255, rxload 1/255

Encapsulation ARPA, loopback not set

Keepalive set (10 sec)

ARP type: ARPA, ARP Timeout 04:00:00

Last input 00:00:12, output 00:00:06, output hang never

Last clearing of "show interface" counters never

Queueing strategy: fifo

Output queue 0/40, 0 drops; input queue 0/75, 1792311 drops

5 minute input rate 3000 bits/sec, 7 packets/sec

5 minute output rate 49000 bits/sec, 10 packets/sec

177995308 packets input, 2874617768 bytes, 7 no buffer

Received 23367 broadcasts, 0 runts, 0 giants, 0 throttles

142 input errors, 0 CRC, 0 frame, 0 overrun, 142 ignored

0 input packets with dribble condition detected

309517996 packets output, 3753149070 bytes, 0 underruns

3175 output errors, 0 collisions, 1 interface resets

0 babbles, 0 late collision, 0 deferred

3175 lost carrier, 0 no carrier

0 output buffer failures, 0 output buffers swapped out

my question is is it a router issue or something on the internal network that is causing the router to freeze up? I'm leaning towards the router. Your thoughts would be appreciated....thank you in advance.


Re: Router unreachable for 5 min

The issue may be due to the interface flapping. The dampening command is entered in interface configuration mode to enable the IP Event Dampening feature. If this command is applied to an interface that already has dampening configured, all dampening states are reset and the accumulated penalty will be set to 0. If the interface has been dampened, the accumulated penalty will fall into the reuse threshold range, and the dampened interface will be made available to the network. The flap counts, however, are retained

New Member

Re: Router unreachable for 5 min

Thank you for that I will check that out but just a FYI I noticed that on both sides the local router and remoter router the debug ip packet detail was left on ever since I killed them the connection hasn't gone down in 2 days so I'm letting this run the reset of the week and if it is still good then I think it was the debugs that was left on. But in the mean time I will also check out what you have suggested as well. Thank you for that

Re: Router unreachable for 5 min

Have you checked the uptime by means of the "sh ver" command?

It might be executing a reload.



Re: Router unreachable for 5 min

Hi there.

it might well be the debug as u found out urself.

u might also want to check traffic statistics to see if there are any correlations betwee high peaks and loss of reachability. if a link is badly congested, routing updates will also fail.