Nortel 5510 - Stack loopback tests

Diagnostic information in the CLI 73
show stack port-statistics {down-stack|up-stack} [unit<1-8>]
where down-stack displays the statistics from the down stack port from
the requested unit, and up-stack displays the statistics from the up stack
port from the requested unit.
This show stack port-statistics command is available in the
PrivExec mode.
clear stack port-statistics command
The clear stack port-statistics command clears the statistics
counters.
The syntax for the clear stack port-statistics command is:
clear stack port-statistics {down-stack|up-stack} [unit
<1-8>]
where down-stack clears the statistics from the down stack port from
the requested unit, and up-stack clears the statistics from the up stack
port from the requested unit.
The clear stack port-statistics command is available in the
PrivExec mode.
Stack loopback tests
You can quickly test your stack ports and stack cable using the stack
loopback test. This is very useful when you need to determine whether the
source of the problem is a bad stack cable or a damaged stack port, and
can help prevent unnecessarily sending switches for service.
There are two types of loopback tests. The internal loopback test verifies
that the stack ports are functional.
The external loopback test checks the stack cable to find out if it is the
source of the problem. The external loopback test is done by connecting the
stack uplink port with the stack downlink port, sending a packet from the
uplink port and verifying that the packet is received on the downlink port.
The internal test should always be run first, because the cable tests won’t
be conclusive until the stack ports are proven to be working correctly.
Testing the stack ports
Verify the operation of the stack ports using the internal loopback test.
Prerequisites for testing the stack ports
• Any previous tests have finished running.
Nortel Ethernet Routing Switch 5500 Series
Configuration - System Monitor ing
NN47200-505 03.01 Standard
5.1 27 August 2007
Copyright © 2005 - 2007, Nortel Networks
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