tcpreplay(1)
NAME
tcpreplay - Replay network traffic stored in pcap files
SYNOPSIS
tcpreplay [-flag [value]]... [--opt-name [[=| ]value]]...
<pcap_file(s)>
tcpreplay is a tool for replaying network traffic from files saved with
tcpdump or other tools which write pcap(3) files.
DESCRIPTION
This manual page briefly documents the tcpreplay command. The basic operation of tcpreplay is to resend all packets from the input file(s) at the speed at which they were recorded, or a specified data rate, up to as fast as the hardware is capable. Optionally, the traffic can be split between two interfaces, written to files, filtered and edited in various ways, providing the means to test firewalls, NIDS and other network devices. For more details, please see the Tcpreplay Manual at: http://tcpreplay.synfin.net/trac/wiki/manual
OPTIONS
-d number, --dbug=number
Enable debugging output. This option may appear up to 1 times.
This option takes an integer number as its argument. The value
of number is constrained to being:
in the range 0 through 5
The default number for this option is:
0
If configured with --enable-debug, then you can specify a
verbosity level for debugging output. Higher numbers increase
verbosity.
-q, --quiet
Quiet mode.
Print nothing except the statistics at the end of the run
-T string, --timer=string
Select packet timing mode: select, ioport, rdtsc, gtod, nano,
abstime. This option may appear up to 1 times. The default
string for this option is:
gtod
Allows you to select the packet timing method to use:
nano - Use nanosleep() API
select - Use select() API
ioport - Write to the i386 IO Port 0x80
rdtsc - Use the x86/x86_64/PPC RDTSC
gtod [default] - Use a gettimeofday() loop
abstime - Use OS X's AbsoluteTime API
--sleep-accel=number
Reduce the amount of time to sleep by specified usec. This
option takes an integer number as its argument. The default
number for this option is:
0
Reduce the amount of time we would normally sleep between two
packets by the specified number of usec. This provides a "fuzz
factor" to compensate for running on a non-RTOS and other
processes using CPU time. Default is disabled.
--rdtsc-clicks=number
Specify the RDTSC clicks/usec. This option may appear up to 1
times. This option takes an integer number as its argument.
The default number for this option is:
0
Override the calculated number of RDTSC clicks/usec which is
often the speed of the CPU in Mhz. Only useful if you specified
--timer=rdtsc
-v, --verbose
Print decoded packets via tcpdump to STDOUT. This option may
appear up to 1 times.
-A string, --decode=string
Arguments passed to tcpdump decoder. This option may appear up
to 1 times. This option must appear in combination with the
following options: verbose.
When enabling verbose mode (-v) you may also specify one or more
additional arguments to pass to tcpdump to modify the way
packets are decoded. By default, -n and -l are used. Be sure
to quote the arguments like: -A "-axxx" so that they are not
interpreted by tcpreplay. Please see the tcpdump(1) man page
for a complete list of options.
-K, --enable-file-cache
Enable caching of packets to internal memory. This option must
appear in combination with the following options: loop.
Cache pcap file(s) the first time they are cached in RAM so that
subsequent loops don't incurr any disk I/O latency in order to
increase performance. Make sure you have enough free RAM to
store the entire pcap file(s) in memory or the system will swap
and performance will suffer.
--preload-pcap
Preloads packets into RAM before sending.
This option loads the specified pcap(s) into RAM before starting
to send in order to improve replay performance while introducing
a startup performance hit. Preloading can be used with or
without --loop and implies --enable-file-cache.
-c string, --cachefile=string
Split traffic via a tcpprep cache file. This option may appear
up to 1 times.
-i string, --intf1=string
Server/primary traffic output interface. This option may appear
up to 1 times.
-I string, --intf2=string
Client/secondary traffic output interface. This option may
appear up to 1 times. This option must appear in combination
with the following options: cachefile.
--listnics
List available network interfaces and exit.
-l number, --loop=number
Loop through the capture file X times. This option may appear
up to 1 times. This option takes an integer number as its
argument. The value of number is constrained to being:
greater than or equal to 0
The default number for this option is:
1
--pktlen
Override the snaplen and use the actual packet len. This option
may appear up to 1 times.
By default, tcpreplay will send packets based on the size of the
"snaplen" stored in the pcap file which is usually the correct
thing to do. However, occasionally, tools will store more bytes
then told to. By specifying this option, tcpreplay will ignore
the snaplen field and instead try to send packets based on the
original packet length. Bad things may happen if you specify
this option.
-L number, --limit=number
Limit the number of packets to send. This option may appear up
to 1 times. This option takes an integer number as its
argument. The value of number is constrained to being:
greater than or equal to 1
The default number for this option is:
-1
By default, tcpreplay will send all the packets. Alternatively,
you can specify a maximum number of packets to send.
-x string, --multiplier=string
Modify replay speed to a given multiple. This option may appear
up to 1 times. This option must not appear in combination with
any of the following options: pps, mbps, oneatatime, topspeed.
Specify a floating point value to modify the packet replay
speed. Examples:
2.0 will replay traffic at twice the speed captured
0.7 will replay traffic at 70% the speed captured
-p number, --pps=number
Replay packets at a given packets/sec. This option may appear
up to 1 times. This option must not appear in combination with
any of the following options: multiplier, mbps, oneatatime,
topspeed. This option takes an integer number as its argument.
-M string, --mbps=string
Replay packets at a given Mbps. This option may appear up to 1
times. This option must not appear in combination with any of
the following options: multiplier, pps, oneatatime, topspeed.
Specify a floating point value for the Mbps rate that tcpreplay
should send packets at.
-t, --topspeed
Replay packets as fast as possible. This option must not appear
in combination with any of the following options: mbps,
multiplier, pps, oneatatime.
-o, --oneatatime
Replay one packet at a time for each user input. This option
must not appear in combination with any of the following
options: mbps, pps, multiplier, topspeed.
Allows you to step through one or more packets at a time.
--pps-multi=number
Number of packets to send for each time interval. This option
must appear in combination with the following options: pps.
This option takes an integer number as its argument. The value
of number is constrained to being:
greater than or equal to 1
The default number for this option is:
1
When trying to send packets at very high rates, the time between
each packet can be so short that it is impossible to accurately
sleep for the required period of time. This option allows you
to send multiple packets at a time, thus allowing for longer
sleep times which can be more accurately implemented.
-P, --pid
Print the PID of tcpreplay at startup.
--stats=number
Print statistics every X seconds. This option takes an integer
number as its argument. The value of number is constrained to
being:
greater than or equal to 1
Note that this is very much a "best effort" and long delays
between sending packets may cause equally long delays between
printing statistics.
-V, --version
Print version information.
-h, --less-help
Display less usage information and exit.
-H, --help
Display usage information and exit.
-!, --more-help
Extended usage information passed thru pager.
- [rcfile], --save-opts[=rcfile]
Save the option state to rcfile. The default is the last
configuration file listed in the OPTION PRESETS section, below.
- rcfile, --load-opts=rcfile, --no-load-opts
Load options from rcfile. The no-load-opts form will disable
the loading of earlier RC/INI files. --no-load-opts is handled
early, out of order.
OPTION PRESETS
Any option that is not marked as not presettable may be preset by
loading values from configuration ("RC" or ".INI") file(s). The homerc
file is "$$/", unless that is a directory. In that case, the file
".tcpreplayrc" is searched for within that directory.
SIGNALS
tcpreplay understands the following signals: SIGUSR1 Suspend tcpreplay SIGCONT Restart tcpreplay
SEE ALSO
tcpreplay-edit(1), tcpdump(1), tcpprep(1), tcprewrite(1), libnet(3)
BUGS
tcpreplay can only send packets as fast as your computer's interface, processor, disk and system bus will allow. Packet timing at high speeds is a black art and very OS/CPU dependent. Replaying captured traffic may simulate odd or broken conditions on your network and cause all sorts of problems. In most cases, you can not replay traffic back to/at a server. Some operating systems by default do not allow for forging source MAC addresses. Please consult your operating system's documentation and the tcpreplay FAQ if you experience this issue.
AUTHOR
Copyright 2000-2010 Aaron Turner For support please use the [email protected] mailing list. The latest version of this software is always available from: http://tcpreplay.synfin.net/ Released under the Free BSD License. This manual page was AutoGen-erated from the tcpreplay option definitions. (tcpreplay ) 2010-04-04 TCPREPLAY(1)
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