which debug command i can use?

Unanswered Question
Jul 14th, 2008

Hello netpro:

I have a 1841+vwic e1 g703 , the e1 link is always flapping ,i want to capture the erro, which debug command i can use ,the ios is 12.4.10c.

thanks for your help


I have this problem too.
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tajuddinmd Tue, 07/15/2008 - 01:28

Hi Zhou,

You can use the following commands.

show controller e1 - This is to verify the configuration if it matches to the remote end router

show isdn status - This will display the summary of the ISDN interfaces.

debug isdn q921 - Ensure that the logging console or terminal monitor is configured before debugging.




jj-zhou Tue, 07/15/2008 - 05:25

Hi Taj:

thanks for your response, but there is no isdn application on my router even not sh isdn command.I want capture the err packets, just like using debug ppp negotiation command ,we could get a lot log.

thank u


patrickvanham Tue, 07/15/2008 - 06:15

the show controller e1 command is very useful especially with the link flapping. There might be a clocking issue causing the flaps.

jj-zhou Wed, 07/16/2008 - 23:05

as below display ,you can see there're lots of violations, and the link is flapping in night generally.and the router connect to a sp modem .if I could judge there is some uncompatible between them.


cn-pek-vertu-rtr01#sh contr e1

E1 0/0/0 is up.

Applique type is Channelized E1 - balanced

No alarms detected.

alarm-trigger is not set

Version info Firmware: 20060623, FPGA: 20, spm_count = 0

Framing is CRC4, Line Code is HDB3, Clock Source is Line.

CRC Threshold is 320. Reported from firmware is 320.

Data in current interval (213 seconds elapsed):

0 Line Code Violations, 0 Path Code Violations

0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins

0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail Secs

Total Data (last 24 hours)

145 Line Code Violations, 45 Path Code Violations,

0 Slip Secs, 0 Fr Loss Secs, 34 Line Err Secs, 0 Degraded Mins,

37 Errored Secs, 3 Bursty Err Secs, 2 Severely Err Secs, 0 Unavail Secs

tajuddinmd Tue, 07/15/2008 - 17:23

Hi Zhou,

What is this controller used for. Can you provide the running config for this interface.




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