Zhone Technologies 900 ユーザーズマニュアル

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Model No.

Running Head

Refer to Appendix B in the System Reference Guide for further information on Error 
Messages regarding this card.

ISDN-PRI card problems could indicate a number of possible causes, including:

Faulty ISDN PBX/CPE at the near end (where the problem was first noticed)

Faulty ISDN PBX/CPE at the far (opposite) end

T1 or E1 network failure

T1 or E1 D-channel failure

Improper network switch configuration

Improper ISDN-PRI card configuration

Typically, a problem is indicated by the inability to originate or receive/route calls. You can 
perform numerous tasks to isolate the trouble and clear it. When troubleshooting problems on 
a call routing through an ISDN-PRI card, follow this general sequence:

1. If all calls are affected, verify that the US/EUR jumper is correctly placed to match the 

US/EUR jumper on the chassis. The ISDN-PRI card performs a self-test on power-up. 
A “healthy” card will have a green LED lit on the front panel. Do not proceed with 
further steps until a green LED is present.

2. Verify that the T1 or E1 network is working properly by checking for current CGA-Red 

and CGA-Yellow alarms. If an ISDN-PRI DS-1 is faulty, a D-channel alarm will also 
be present. If no CGA alarms on ISDN-PRI DS-1s are present, but a D-channel alarm 
is present continue with step 3. If there is no D-channel alarm continue with step 4.

3. A D-channel alarm will be posted if the ISDN D-channel is not communicating 

properly with the ISDN switch/PBX connected to the WAN port. Verify the 
configuration settings for the affected ISDN port. Be sure the port is connected to the 
proper WAN card and port, that the correct SIDE (net or user) is selected and that the 
appropriate SW. TYPE has been chosen. If these assignments appear correct, it may be 
necessary to consult with the network or PBX provider to clear the D-channel alarm. 
Do not proceed with further steps until the D-channel alarm is cleared. In the alarm 
filter screen DCHAN alarm needs to be set as “log” or “report” to see ISDN D channel 
alarms (the default is “ignore”).