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1721 158453 input errors, 8891 CRC, 68503 frame, 0 overrun, 0 ignored, 8105

Is this a T1 Line problem or a E1/T1 WIC problem? We are having odd problems at this office. Verizon said that the T1 Line tested ok however, They don't have stress on it when they test.

Serial0 is up, line protocol is up

Hardware is PQUICC with Fractional T1 CSU/DSU

Internet address is

MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,

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

Encapsulation HDLC, loopback not set

Keepalive set (10 sec)

Last input 00:00:00, output 00:00:01, output hang never

Last clearing of "show interface" counters 15:15:37

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 512

Queueing strategy: weighted fair

Output queue: 0/1000/64/484 (size/max total/threshold/drops)

Conversations 0/4/256 (active/max active/max total)

Reserved Conversations 0/0 (allocated/max allocated)

Available Bandwidth 1158 kilobits/sec

5 minute input rate 1000 bits/sec, 1 packets/sec

5 minute output rate 0 bits/sec, 1 packets/sec

495629 packets input, 45379504 bytes, 0 no buffer

Received 5419 broadcasts, 0 runts, 3 giants, 0 throttles

158453 input errors, 8891 CRC, 68503 frame, 0 overrun, 0 ignored, 81057 abo


514140 packets output, 47767968 bytes, 0 underruns

0 output errors, 0 collisions, 283 interface resets

0 output buffer failures, 0 output buffers swapped out

10 carrier transitions

DCD=up DSR=up DTR=up RTS=up CTS=up


Re: 1721 158453 input errors, 8891 CRC, 68503 frame, 0 overrun,

Further troubleshooting needs to be done to better locate the problem.

Start by doing a T1 loopback test using a T1 loop-plug cable plugged into the FT1. You will need to set the encaps to HDLC and clock to internal. This will test the entire WIC. The interface will come up/up if the loopback is good and you can run some extended pings to yourself with large datasize for a few minutes. See if the errors go up. If they don't with this test then your hardware is most likely fine and it's a circuit issue. You can then extend the loopback test to the smartjack perhaps - and plug the T1 loop cable in the telco side of the smartjack if it has one. This will test from the router , through the SJ and back. If this is fine then the problems beyond the smartjack....

Can verizon see your smartjack and CSU (FT1) ? Throw them a loop and see if they see errors... You can also have them throw a loop your way from the local switch to see if errors continue. If this is clean, then the problem could be in their network beyond where the loop was done. There may be other carriers involved as well.

HTH, Erick


Re: 1721 158453 input errors, 8891 CRC, 68503 frame, 0 overrun,

ebergquist made great suggestions. Here are a few more:

Make sure that the line really is configured the way you think it is (or at least the way you have it configured!). Check that the circuit really is ESF/B8ZS and that that is whaw you have. Also, try changing the clock source from line to internal (or internal to line). Also, it appears that you have an integrated CSU. Try do "sho service module serial 1" (or something similar, I don't have a router in front of me that has WIC's!). The output from that should give you (or us!) some more hints...

New Member

Re: 1721 158453 input errors, 8891 CRC, 68503 frame, 0 overrun,

Thanks for the info. It turned out to be a Verison issue. You need to have them run an Octive 55 test. That is the only way they can find a Repeter that will pass the regular line tests however, is otherwise defective. Once the Repeter was replaced all was back to Abbey Normal.


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