Troubleshooting Istsessiondown Message Using Cli Or Acli; Troubleshooting Bpdu Filtering; No Packets Received On The Port - Avaya 8800 Troubleshooting Manual

3. Check interface status:
Troubleshooting IstSessionDown message using CLI or
ACLI
If the Avaya Ethernet Routing Switch 8800/8600 shows the log message IstSessionDown
for no apparent reason or additional information as to why, use show mlt ist stats (CLI)
or show ist stat (ACLI) to determine if a switch is having difficulty sending or receiving the
IST messages.
The normal IST message timeout is 50 seconds and is affected by the port link state. If the
lowest numbered port is up, the IST mechanism sends IST messages on this link and expects
to receive them on this link. A failure of the lowest numbered link results in failover to the 2nd
lowest, but the IST always tries to return to the lowest link whenever the link state is up.
Trace level 25 can show the IST messages being exchanged over the IST.
trace level 25 <1-4> trace screen on (CLI or ACLI)
Also, enabling VLACP on the IST links can guard against link failures, where the link remains
up but the link cannot transmit or receive the IST messages reliably.

Troubleshooting BPDU filtering

The following sections provide information for troubleshooting BPDU filtering issues.

No packets received on the port

In order for BPDU filtering to work on a port, BPDU packets must be received on that port. To
troubleshoot cases when no packets are received on a port, use the following procedure.
1. Display the BPDU filtering status for the port:
Troubleshooting
Verify that the correct ports are members of the MLTs, and that the trunk is
enabled.
show ip interface
Verify that, for each interface, the port state is enabled, and its operational state is
up. If they are not, try to disable then reenable the port. If the ports do not come up,
there may be a physical layer issue.
show bpdu-filter 4/1 (CLI)

Troubleshooting IstSessionDown message using CLI or ACLI

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