User`s guide

Performing Loopback Modes and Pattern Tests
6-3
7800-A2-GB26-80
May 1999
Diagnosing Problems with the Management Link
You can manage a device from OpenView through an Ethernet, leased-line, or
dial-up connection. If the management connection is lost to a functional (green)
device, the device symbol that is displayed on the OpenView submap turns blue
and the line connected to it turns red. The colors of the interface symbols on the
Device Display correspond to their last known states. An unknown (blue) state
may be the norm if you are managing a device only periodically over a dial-up
connection.
Without a management connection to the device, diagnosis using the DCE
Manager is impossible. Therefore, you should perform an on-site test of the
device to determine whether the problem is in the device or in the line. The
individual device manuals provide a troubleshooting section that describes how to
diagnose problems. The device manuals also describe how to run the device
self-test.
It may be possible to test the device using the device’s terminal interface, which
is accessible through a Telnet connection. Refer to the individual device manuals.
See
Diagnosing Problems with Device or Line below.
Diagnosing Problems with the Device or Line
When the DCE Manager detects that one of the device interfaces is in a down
(or alarm) state, the following symbols turn red:
H Interface symbol on the Device Display
H Device symbol that is displayed on the OpenView submap
This state is reflected in the Operational Status field of the appropriate Health and
Status dialog. Using the DCE Manager, you can place these interfaces in
loopback mode and run pattern tests to help you isolate the problem.
When you are notified of a problem with a particular interface, try to determine
whether or not the failure resulted from a problem with any of the following:
H The device itself
H Line
H Remote device
The sections that follow describe how you can use the loopback modes in
combination with the pattern tests to do this. If you isolate a failure to a device,
you may want to run the device self-test, as described in the troubleshooting
section of some device manuals. If you isolate a failure to the network or to a
device not supported by the DCE Manager, contact the network administrator or
refer to the device manual.