How to perform a network trace
From Wiki-UX.info
1) In order to run the trace you need to follow these steps:
Step 1: Begin LAN Tracing to a Raw Trace File:
# nettl -tn all -e ns_ls_ip -mem 1024 -tracemax 99999 -f /tmp/raw0
This will trace packets in, packets out, and loopback packets at the IP
Layer (ns_ls_ip).
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Step 2: Reproduce the Network "Event" or Error Condition
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Step 3: Stop Tracing to the Raw Trace File As Soon As Possible
# nettl -tf -e all
or
1. Start the trace on the NFS client and server systems:
# nettl -tn pduin pduout -e ns_ls_ip -tm 99999 -f /tmp/raw0
2. Quickly execute a command that will hang on the NFS client.
3. Quickly stop the trace on both systems (once the command hangs):
# nettl -tf -e all