User`s guide

Diagnostics
6-4
5100-A2-GB20-00
November 1996
Using the Loopback Tests
When you encounter a problem with a HotWire connection, try to determine
whether the problem is in the:
H LAN Network
H POTS service
H Local CO card
H Remote CP card
You can become aware of a problem through poor performance statistics or error
conditions reported by the local management utility (Chapter 4). LEDs on the CO
and CP card also have error states as described in
LED Status on page 6-2.
Use the following procedure when you encounter a problem.
" Procedure
1. Run the LAN loopback as described in LAN Loopback on page 6-5 to verify
that the back-end network and Ethernet circuitry of the CO card are
operational. If the LAN loopback is successful, go to Step 2.
2. Run the local loopback as described In
Local Loopback on page 6-5 to
verify that the ISA data path circuitry of the CO card is operational.
If neither the LAN or the local loopback detects an error, the likelihood is that
the problem is in the POTS facility or CP card.
Go to Step 3.
3. Run the remote loopback as described in
Remote Loopback on page 6-6 to
verify that the DSL circuitry of the CO card, the POTS network and the DSL
circuity of the CP card are operational.
If the remote loopback is successful, the problem is likely to be in the
application software or network setup.
If the remote loopback is unsuccessful, go to Step 4.
4. If the error condition persists, swap in another CO card and repeat
Steps 1 though 3.
5. If the error condition still persists, swap in another CP card and repeat
Steps 1 though 3.
You initiate and terminate the loopback tests from the Diagnostic screen of the
local management utility described in
Diagnostics in Chapter 4.