ISDN Dial backup for Frame Relay

[jbrots04]

I'm running Frame Relay w/ISDN dial backup to 20 sites. I can't get one in Chicago to work. All sites have the same configuration. I'm using Cisco 2503 routers with Adtran NT1 ACE terminating the ISDN line for the BRI interface. The phone company said the line tests clean from the rj45 jack, however when I type a show isdn stat on my router the physical layer is down. I have tested the hardware/cables here and it works without any problems.

Is anyone running a similiar configuration, and if so, can you recommend a different solution for me to try?

Any help is greatly appreciated.

Thanks,
Jeff

 

[vipergg]

Have you tried changing isdn switch types ? When you run debug for isdn are you seeing any transmissions from the telco ? If not it's some type of physical layer issue .

 

[jbrots04]

The isdn switch-type is basic-ni1.

Here's a copy of the log, please let me know what you think.


#sho log
Syslog logging: enabled (0 messages dropped, 0 flushes, 0 overruns)
Console logging: disabled
Monitor logging: level debugging, 0 messages logged
Trap logging: level debugging, 1382 message lines logged
Logging to 172.20.50.70, 1382 message lines logged
Buffer logging: level debugging, 1378 messages logged

Log Buffer (4096 bytes):

ISDN BR0: Event: Call to 101033312154469041 at 64 Kb/s
ISDN BR0: Activating
ISDN BR0: TX -> IDREQ ri = 11759 ai = 127
ISDN BR0: TX -> IDREQ ri = 3296 ai = 127
ISDN BR0: TX -> IDREQ ri = 56033 ai = 127
%ISDN-6-LAYER2DOWN: Layer 2 for Interface BRI0, TEI 255 changed to down
ISDN BR0: received HOST_DISCONNECT_ACK
ISDN BR0: TX -> IDREQ ri = 35058 ai = 127
ISDN BR0: Event: Call to 101033312154469041 at 64 Kb/s
ISDN BR0: Activating
ISDN BR0: Physical layer is IF_DOWN
ISDN BR0: Shutting down ME
ISDN BR0: Shutting down ISDN Layer 3

 

[Challenger]

Hi Jeff,
Try doing some isdn debugging, carefull when you debug though if it's a busy router !

debug isdn ?
events ISDN events
q921 ISDN Q921 packets
q931 ISDN Q931 packets

Here in Australia we get some rx packets on either q921 or q931 at regular intervals if the isdn line is available but not in use by the router. the events debug will give you everything so it's a good one to put on and then try to fire up the back-up link.
Steve.

 

[jbrots04]

Steve,

I have the isdn debugging turned on for the log above. I then tried sending a ping over the isdn line.

#sho debug
ISDN:
ISDN events debugging is on
ISDN Q921 packets debugging is on
ISDN Q931 packets debugging is on

Any idea on what the log output suggests? Thanks for your help.

Jeff

 

[Challenger]

Well, there are tx transmit packets, but no rx receive, do you have access to the Adtran box ? I'm not familiar with them but had a quick google and they seem to have some setting switches and also in the troubleshooting they mention some leds for fault diagnoses, if the telco reckons the lines ok it's the next step ! If you haven't already !
But the debug seems very 1 one way, all transmit, but nothing coming back.
Steve.

 

[dnftech]

It sounds to me like you need to strap the Adtran NT1 ACE.
If you strap it (configure it) incorectly it will cause this type of error. you also need to check the connector on the back (v.35 or dp25) and see if there are any bad pins.
Of course you need to cable check your isdn cable from your dmark to the unit.

This is what I usualy chekc first in these situaltions.

Frank


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