Chapter 3 Troubleshooting

Table 3-4

Troubleshooting ISDN (Continued)

 

 

 

 

 

WAN Interface

 

 

 

Card

Symptom(s)

Check the Following

Possible Causes

 

 

 

 

ISDN S/T

Card cannot

Use show isdn status

 

or

make a

command to check the

 

ISDN U

connection to the

following:

 

 

remote router.

• Does the current ISDN

• Use the isdn switch-typecommand to

 

 

 

 

switch type match actual

configure correct switch type.

 

 

switch type being used?

 

Is Layer 1 status deactivated?

Use the show controller bri0 command to check for the messages CO RUNNING LOOPBACK TESTS or CO TESTING. If you receive these messages, contact the service provider.

If Layer 1 status is active, does Layer 3 status say “2 Active Layer 3 calls”?

Router might have called itself. Check destination phone number configured with the dialer map command or the dialer string command.

 

• If Layer 1 status is active,

• Check destination phone number and

 

does Layer 3 status say

make sure it matches the remote router

 

“No Active Layer 3

phone number. Check route to the

 

call(s)”?

destination and make sure it matches

 

 

the remote router network address.

 

 

 

 

• If Layer 1 status is active,

• Check router protocol configurations.

 

does Layer 3 status say “1

 

 

Active Layer 3 call”?

 

 

 

 

 

Cisco 1700 Router Hardware Installation Guide

3-12

78-5405-03

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Cisco Systems 1700 manual Troubleshooting Isdn, Use show isdn status