Reference Guide for the Model RT210/RT211 ISDN Routers
5-4 Troubleshooting
Correct provisioning of your ISDN line is important. Because there are many different service
packages offered in North America, which all have different parameters set in the central office
switch, you might experience malfunctions in your ISDN line. If you suspect that your line is not
working properly, you can verify its operation by making a loopback test. The loopback test calls
out on one B channel and back in on the other B channel.
To make a loopback test, follow these steps:
1. Type SAVE to save your current configuration.
When the router connects back to itself in the loopback test, a path with the name of the router
is created. After testing, discard this path.
2. Type STAT ISDN to connect to the ISDN Port Status screen.
ISDN01 should be highlighted, and both ports must be idle.
3. Type CALL to place a call.
CALL should be followed by a space and the number of the ISDN line assigned to the router.
If you have given a different local number to each B channel, use the one you configured under
ISDN02. A busy signal, clearing code 17, is received if you are using the number configured
under ISDN01.
If there are no problems, the ISDN Port Status screen shows both the outgoing and incoming
calls made from and to the unit. If there is a problem, the error code sent by the network or
generated internally is displayed on the ISDN01 status line.
For additional information on clearing codes, refer to Table 5-1 and Table 5-2.
The most common ISDN problems are:
• Code 50
The line has not been provisioned correctly.
• Code 146
The local directory number or SPID has been set incorrectly. Check your line
configuration with the telephone company and request the local directory number and
SPID that you should use.
4. Type REBOOT to reboot the router and restore the saved configuration.
NGRRT210.BK Page 4 Friday, October 17, 1997 2:37 PM