Packet Capture - Nortel NN46110-602 Troubleshooting Manual

Chapter 5

Packet capture

Packet capture (PCAP) is a troubleshooting tool that network administrators and
customer support personnel use, in conjunction with other tools such as statistics,
logging, network analyzers, and testers, to remotely troubleshoot VPN Router and
network problems. Packet capture is especially useful for troubleshooting the
VPN Router 1010/1050/1100, which is typically located in a small office where
no technical expertise is available. You can only configure PCAP with the
command line interface (CLI).
There are two options when capturing packets:
•
•
When capturing packets traversing the VPN Router, you can do one of the
following:
•
•
No packet loss—captures all packets. If the RAM buffer is full, a forced flush
to disk occurs.
Packet loss—skips some packets. If the RAM buffer is full, the VPN Router
drops packets and inserts a malformed packet in the place where the packets
were not captured. The malformed packet stores the number of dropped
packets.
Note: While capturing packets with packet loss does not affect
forwarding performance, capturing packets with no packet loss can
affect performance.
write them to files in a circular buffer of maximum 999 files
write them to stop when the specified maximum number of files is reached
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