Deployment Guide

Parameters
cp Enter the keyword cp to perform a dump on traffic processed by the Control
Processor CPU.
rp Enter the keyword rp to perform a dump on traffic processed by the Route
Processor CPU.
capture-duration Enter the time for packet capturing. The timer begins as soon as the command is
enabled. The range is 20 to 9000 seconds.
filter Specify the packet that will be dumped. If no filter is entered, all packets are
dumped. Filter expressions usually consist of an id (name or num ber) preceded by
one or more qualifiers. There are three different kinds of qualifier: type, direction,
or protocol.
Enclose the filter option with double quotes: “port 20.” The range is 1 to 100
characters.
max-file-count Enter the maximum number of 1MB files. 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
number. The range is 1 to 20.
packet-count Enter the number of packets to capture. The counter begins as soon as the
command is enabled. The range is 10 to 150000.
snap-length Enter the number of bytes per packet to capture. Use this option to reduce the
size of the captured packets, to capture only the needed headers and avoid rest of
the data portion of the packet. The range is 0 to 1200.
write-to Enter the location to save the captured packets. Files can be saved to flash, to
FTP, SCP, or TFTP:
● flash://filepath
● ftp://userid:password@hostip/filepath
● scp://userid:password@hostip/filepath
● tftp://hostip/filepath
Defaults TCP dumps are disabled.
Command Modes EXEC Privilege
Command
History
This guide is platform-specific. For command information about other platforms, refer to the relevant Dell
Networking OS Command Line Reference Guide.
The following is a list of the Dell Networking OS version history for this command.
Version Description
9.9(0.0) Introduced on the C9010.
9.2(1.0) Introduced on the Z9500.
8.3.19.0 Introduced on the S4820T.
8.3.11.1 Introduced on the Z9000.
8.3.7.0 Introduced on the S4810.
Usage
Information
Use the tcpdump command to perform a packet capture on a specified switch CPU: Control Processor
(CP) or Route Processor (RP).
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.
The files saved on the flash are located in the flash://TCP_DUMP_DIR/Tcpdump_<time_stamp_dir>/
directory. The file name is tcpdump_*.pcap. There can be up to 20 Tcpdump_<time_stamp_dir>
directories. If more than 20 files are created, the oldest is overwritten.
Entering the no tcpdump command stops any TCP dump process running in either the Control
Processor or Route Processor. The dump stops immediately, without waiting for a threshold to be met.
614 Debugging and Diagnostics