.TH TCPREPLAY 1 2008-01-16 "(tcpreplay )" "Programmer's Manual" .\" DO NOT EDIT THIS FILE (tcpreplay.1) .\" .\" It has been AutoGen-ed Wednesday January 16, 2008 at 10:09:46 PM PST .\" From the definitions tcpreplay_opts.def .\" and the template file agman1.tpl .\" .SH NAME tcpreplay \- Replay network traffic stored in pcap files .SH SYNOPSIS .B tcpreplay .\" Mixture of short (flag) options and long options .RB [ \-\fIflag\fP " [\fIvalue\fP]]... [" \--\fIopt-name\fP " [[=| ]\fIvalue\fP]]..." .br .in +8 .PP tcpreplay is a tool for replaying network traffic from files saved with tcpdump or other tools which write pcap(3) files. .SH "DESCRIPTION" This manual page documents, briefly, the \fBtcpreplay\fP 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 .SH OPTIONS .TP .BR \-d " \fInumber\fP, " \--dbug "=" \fInumber\fP Enable debugging output. This option may appear up to 1 times. This option takes an integer number as its argument. The value of \fInumber\fP is constrained to being: .in +4 .nf .na in the range 0 through 5 .fi .in -4 The default \fInumber\fP for this option is: .ti +4 0 .sp If configured with \--enable-debug, then you can specify a verbosity level for debugging output. Higher numbers increase verbosity. .TP .BR \-q ", " \--quiet Quiet mode. .sp Print nothing except the statistics at the end of the run .TP .BR \-a ", " \--accurate Enable more accurate packet timing. This option may appear up to 1 times. This option must not appear in combination with any of the following options: accurate2. .sp Enables more accurate timing between packets at the cost of higher CPU utilization by using the gettimeofday() system call. This method works better on some systems then others and may have rather non-granular resolution which makes it problematic for replaying at high rates of speed. .TP .BR \--accurate2 "=\fInumber\fP" Enable even more accurate packet timing. This option may appear up to 1 times. This option must not appear in combination with any of the following options: accurate. This option takes an integer number as its argument. .sp Enables the "even more" accurate timing at the cost of higher CPU utilization by using a tight loop which increments a counter. This method provides the most accurate timing of any option, but requires you to specify a cost for each loop. This cost value is VERY system dependent, so you will need to run \--loop-test to get this value. .TP .BR \-v ", " \--verbose Print decoded packets via tcpdump to STDOUT. This option may appear up to 1 times. .sp .TP .BR \-A " \fIstring\fP, " \--decode "=" \fIstring\fP Arguments passed to tcpdump decoder. This option may appear up to 1 times. This option must appear in combination with the following options: verbose. .sp When enabling verbose mode (\fB-v\fP) you may also specify one or more additional arguments to pass to \fBtcpdump\fP 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. .TP .BR \-K ", " \--enable-file-cache Enable caching of packets to internal memory. This option must appear in combination with the following options: loop. .sp 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. .TP .BR \-c " \fIstring\fP, " \--cachefile "=" \fIstring\fP Split traffic via a tcpprep cache file. This option may appear up to 1 times. .sp .TP .BR \-i " \fIstring\fP, " \--intf1 "=" \fIstring\fP Server/primary traffic output interface. This option may appear up to 1 times. .sp .TP .BR \-I " \fIstring\fP, " \--intf2 "=" \fIstring\fP Client/secondary traffic output interface. This option may appear up to 1 times. This option must appear in combination with the following options: cachefile. .sp .TP .BR \--listnics List available network interfaces and exit. .sp .TP .BR \-l " \fInumber\fP, " \--loop "=" \fInumber\fP 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 \fInumber\fP is constrained to being: .in +4 .nf .na greater than or equal to 0 .fi .in -4 The default \fInumber\fP for this option is: .ti +4 1 .sp .TP .BR \--pktlen Override the snaplen and use the actual packet len. This option may appear up to 1 times. .sp 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. .TP .BR \-L " \fInumber\fP, " \--limit "=" \fInumber\fP 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 \fInumber\fP is constrained to being: .in +4 .nf .na greater than or equal to 1 .fi .in -4 The default \fInumber\fP for this option is: .ti +4 \-1 .sp By default, tcpreplay will send all the packets. Alternatively, you can specify a maximum number of packets to send. .TP .BR \-x " \fIstring\fP, " \--multiplier "=" \fIstring\fP 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. .sp Specify a floating point value to modify the packet replay speed. Examples: .nf 2.0 will replay traffic at twice the speed captured 0.7 will replay traffic at 70% the speed captured .fi .TP .BR \-p " \fInumber\fP, " \--pps "=" \fInumber\fP 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. .sp .TP .BR \-M " \fIstring\fP, " \--mbps "=" \fIstring\fP 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. .sp Specify a floating point value for the Mbps rate that tcpreplay should send packets at. .TP .BR \-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. .sp .TP .BR \-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. .sp Allows you to step through one or more packets at a time. .TP .BR \-P ", " \--pid Print the PID of tcpreplay at startup. .sp .TP .BR \-V ", " \--version Print version information. .sp .TP .BR \-h ", " \--less-help Display less usage information and exit. .sp .TP .BR \-H , " \--help" Display usage information and exit. .TP .BR \-! , " \--more-help" Extended usage information passed thru pager. .TP .BR \- " [\fIrcfile\fP]," " \--save-opts" "[=\fIrcfile\fP]" Save the option state to \fIrcfile\fP. The default is the \fIlast\fP configuration file listed in the \fBOPTION PRESETS\fP section, below. .TP .BR \- " \fIrcfile\fP," " \--load-opts" "=\fIrcfile\fP," " \--no-load-opts" Load options from \fIrcfile\fP. The \fIno-load-opts\fP form will disable the loading of earlier RC/INI files. \fI--no-load-opts\fP is handled early, out of order. .SH OPTION PRESETS Any option that is not marked as \fInot presettable\fP may be preset by loading values from configuration ("RC" or ".INI") file(s). The \fIhomerc\fP file is "\fI$$/\fP", unless that is a directory. In that case, the file "\fI.tcpreplayrc\fP" is searched for within that directory. .SH "SIGNALS" tcpreplay understands the following signals: .sp .IR "\fBSIGUSR1\fP" Suspend tcpreplay .sp .IR "\fBSIGCONT\fP" Restart tcpreplay .br .SH "SEE ALSO" tcpreplay-edit(1), tcpdump(1), tcpprep(1), tcprewrite(1), libnet(3) .SH "BUGS" tcpreplay can only send packets as fast as your computer's interface, processor, disk and system bus will allow. Replaying captured traffic may simulate odd or broken conditions on your network and cause 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 experiance this issue. .SH AUTHOR Copyright 2000-2007 Aaron Turner For support please use the tcpreplay-users@lists.sourceforge.net mailing list. The latest version of this software is always available from: http://tcpreplay.synfin.net/ .PP Released under the Free BSD License. .PP This manual page was \fIAutoGen\fP-erated from the \fBtcpreplay\fP option definitions.