How to verify if Telco PRI E1 is working from my Voice Gateway.

Posted on 2014-07-10
Last Modified: 2014-07-14
I have a issue with my telephone system, I am unable to place or receive receive any call. I have forwarded the issue to my Telco and they just performed the loop test and confirm that it is working from there side. Can someone advise for a steps on the terminal to verify that the router is working perfectly and Telco has issue on there side. I have the following setup:

- PRI E1
- Cisco 2800 series

Voice-Gw#show controllers e1
E1 0/0/0 is up.
  Applique type is Channelized E1 - balanced
  No alarms detected.
  alarm-trigger is not set
  Version info Firmware: 20060711, FPGA: 13, 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 (547 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 66 15 minute intervals):
     56065 Line Code Violations, 204 Path Code Violations,
     3 Slip Secs, 4 Fr Loss Secs, 5 Line Err Secs, 1 Degraded Mins,
     4 Errored Secs, 0 Bursty Err Secs, 4 Severely Err Secs, 309 Unavail Secs

Voice-Gw#show isdn status
Global ISDN Switchtype = primary-net5
ISDN Serial0/0/0:15 interface
        dsl 0, interface ISDN Switchtype = primary-net5
    Layer 1 Status:
    Layer 2 Status:
        TEI = 0, Ces = 1, SAPI = 0, State = MULTIPLE_FRAME_ESTABLISHED
    Layer 3 Status:
        0 Active Layer 3 Call(s)
    Active dsl 0 CCBs = 0
    The Free Channel Mask:  0xFFFF7FFF
    Number of L2 Discards = 0, L2 Session ID = 16
    Total Allocated ISDN CCBs = 0

I am suspecting an issue with the PRI connection and I wanted to confirm and forward it to my Telco. Let me know if you need me to run any terminal commands. Thanks in advance.
Question by:pvelasquez
    LVL 34

    Expert Comment

    by:Istvan Kalmar

    I advise to use:

    debug isdn q931 when you want to call

    If you need more support please end us the config, and the log

    Author Comment

    Hello ikalmar. please find attached files. Thanks!
    LVL 20

    Accepted Solution

    You might want to look into these links. The call disconnect cause is where you need to start troubleshooting.

    At least the calls look like they are coming in fine from the provider, seems to be a local issue. Most likely a DSP or codec issue.
    LVL 34

    Assisted Solution

    by:Istvan Kalmar
    Hi do you have enough DSP in your router?

    Please provide us "sh inventory" output

    Author Closing Comment

    Thanks a lot guys

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