Dell S4048T, Руководство по настройке

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Enabling TCP Dumps
A TCP dump captures CPU-bound control plane traffic to improve troubleshooting and system
manageability. When you enable TCP dump, it captures all the packets on the local CPU, as specified in the
CLI.
You can save the traffic capture files to flash, FTP, SCP, or TFTP. The files saved on the flash are located in the
flash://TCP_DUMP_DIR/Tcpdump_<time_stamp_dir>/ directory and labeled tcpdump_*.pcap . There can be
up to 20 Tcpdump_<time_stamp_dir> directories. The 21st file overwrites the oldest saved file. The maximum
file size for a TCP dump capture is 1MB. When a file reaches 1MB, a new file is created, up to the specified
total number of files.
Maximize the number of packets recorded in a file by specifying the snap-length to capture the file headers
only.
The
tcpdump
command has a finite run process. When you enable the
tcpdump
command, it runs until the
capture-duration timer and/or the packet-count counter threshold is met. If you do not set a threshold, the
system uses a default of a 5 minute capture-duration and/or a single 1k file as the stopping point for the
dump.
You can use the capture-duration timer and the packet-count counter at the same time. The TCP dump
stops when the first of the thresholds is met. That means that even if the duration timer is 9000 seconds, if
the maximum file count parameter is met first, the dumps stop.
To enable a TCP dump, use the following command.
• Enable a TCP dump for CPU bound traffic.
CONFIGURATION mode
tcpdump cp [capture-duration time | filter expression | max-file-count value |
packet-count value | snap-length value | write-to path ]
Debugging and Diagnostics 1262