Cisco 1721 - VPN Security Router Bundle Hardware Installation Manual page 62

Problem Solving
Table 3-4 Troubleshooting ISDN
WIC Symptom(s)
ISDN S/T Router is on,
but OK LED on
the card is off.
ISDN U Router is on,
but the NT-1
LED on the
card is off.
Cisco 1721 Router Hardware Installation Guide
3-12
For routers with an ISDN U WIC, use the clear controller command to
•
terminate any active ISDN calls, to reset the ISDN BRI interface, and to reset
the ISDN line between the router and the central office switch. Do this for
each ISDN port installed in the router:
Router# clear controller bri0
Router# clear controller bri1
Table 3-4 lists troubleshooting methods for ISDN-related problems that
might occur.
Check the Following
• Is the OK LED on the
router front panel on?
Are all ISDN cables
•
properly connected?
Is the NT-1 LED on?
•
Is the OK LED on?
•
Are all ISDN cables
•
properly connected?
Is the ISDN line
•
connected to the card
ISDN U port?
Chapter 3
Possible Causes
• If the OK LED is not on, the
router might be malfunctioning.
Contact your Cisco reseller.
If the cables are properly
•
connected, the ISDN line might
be malfunctioning. Check with
your ISDN service provider.
If the NT-1 LED is not on, the
•
NT1 might be malfunctioning.
If the OK LED is not on, the
•
router might be malfunctioning.
Contact your Cisco reseller.
If the cables are properly
•
connected, the ISDN line might
be malfunctioning. Check with
your ISDN service provider.
If the line is connected to the
•
port, the ISDN line might be
malfunctioning. Check with your
ISDN service provider.
Troubleshooting
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