.TH TCPREPLAY 1 2008-06-09 "(tcpreplay )" "Programmer's Manual"
.\"  DO NOT EDIT THIS FILE   (tcpreplay-edit.1)
.\"  
.\"  It has been AutoGen-ed  Monday June  9, 2008 at 11:05:43 AM PDT
.\"  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
<pcap_file(s)>
.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
.SS ""
.TP
.BR \-r " \fIstring\fP, " \--portmap "=" \fIstring\fP
Rewrite TCP/UDP ports.
This option may appear up to 1 times.
.sp
Specify a list of comma delimited port mappingings consisting of 
colon delimited port number pairs.  Each colon delimited port pair
consists of the port to match followed by the port number to rewrite.

Example:
.nf
    \--portmap=80:8000,8080:80
.fi
.TP
.BR \-s " \fInumber\fP, " \--seed "=" \fInumber\fP
Randomize src/dst IP addresses w/ given seed.
This option may appear up to 1 times.
This option takes an integer number as its argument.
.sp
Causes the source and destination IP addresses to be pseudo 
randomized but still maintain client/server relationships.
Since the randomization is deterministic based on the seed, 
you can reuse the same seed value to recreate the traffic.
.TP
.BR \-N " \fIstring\fP, " \--pnat "=" \fIstring\fP
Rewrite IP addresses using pseudo-NAT.
This option may appear up to 2 times.
This option must not appear in combination with any of the following options:
srcipmap.
.sp
Takes a comma delimited series of colon delimited CIDR
netblock pairs.  Each netblock pair is evaluated in order against
the IP addresses.  If the IP address in the packet matches the
first netblock, it is rewriten using the second netblock as a
mask against the high order bits.

Example:
.nf
    \--pnat=192.168.0.0/16:10.77.0.0/16,172.16.0.0/12:10.1.0.0/24
.fi
.TP
.BR \-S " \fIstring\fP, " \--srcipmap "=" \fIstring\fP
Rewrite source IP addresses using pseudo-NAT.
This option may appear up to 1 times.
This option must not appear in combination with any of the following options:
pnat.
.sp
Works just like the \--pnat option, but only affects the source IP
addresses in the IPv4 header.
.TP
.BR \-D " \fIstring\fP, " \--dstipmap "=" \fIstring\fP
Rewrite destination IP addresses using pseudo-NAT.
This option may appear up to 1 times.
This option must not appear in combination with any of the following options:
pnat.
.sp
Works just like the \--pnat option, but only affects the destination IP
addresses in the IPv4 header.
.TP
.BR \-e " \fIstring\fP, " \--endpoints "=" \fIstring\fP
Rewrite IP addresses to be between two endpoints.
This option may appear up to 1 times.
This option must appear in combination with the following options:
cachefile.
.sp
Takes a pair of colon delimited IP addresses which will be used to rewrite
all traffic to appear to be between the two IP's.

Example:
.nf
    \--endpoints=172.16.0.1:172.16.0.2
.fi
.TP
.BR \-b ", " \--skipbroadcast
Skip rewriting broadcast/multicast IP's.
.sp
By default \--seed, \--pnat and \--endpoints will rewrite 
broadcast and multicast IP and MAC addresses.	Setting this flag
will keep broadcast/multicast IP and MAC addresses from being rewritten.
.TP
.BR \-C ", " \--fixcsum
Force recalculation of IP/TCP/UDP checksums.
.sp
Causes each IP packet to have it's checksums recalcualted and
fixed.  Automatically enabled for packets modified with \fB--seed\fP, 
\fB--pnat\fP, \fB--endpoints\fP or \fB--fixlen\fP.
.TP
.BR \-m " \fInumber\fP, " \--mtu "=" \fInumber\fP
Override default MTU length (1500 bytes).
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  1 through MAXPACKET
.fi
.in -4
.sp
Override the default 1500 byte MTU size for determining the maximum padding length.
.TP
.BR \-E ", " \--efcs
Remove Ethernet checksums (FCS) from end of frames.
.sp
Note, this option is pretty dangerous!  We don't actually check to see if a FCS
actually exists in the frame, we just blindly delete the last two bytes.  Hence,
you should only use this if you know know that your OS provides the FCS when 
reading raw packets.
.TP
.BR \--ttl "=\fIstring\fP"
Modify the IPv4 TTL.
.sp
Allows you to modify the TTL of all the IPv4 packets.  Specify a number to hard-code
the value or +/-value to increase or decrease by the value provided (limited to 1-255).    

Examples:
.nf
    \--ttl=10
    \--ttl=+7
    \--ttl=-64
.fi
.TP
.BR \-F " \fIstring\fP, " \--fixlen "=" \fIstring\fP
Pad or truncate packet data to match header length.
This option may appear up to 1 times.
.sp
Packets may be truncated during capture if the snaplen is smaller then the
packet.  This option allows you to modify the packet to pad the packet back
out to the size stored in the IPv4 header or rewrite the IP header total length
to reflect the stored packet length.
.sp 1
\fBpad\fP
Truncated packets will be padded out so that the packet length matches the 
IPv4 total length
.sp 1
\fBtrunc\fP
Truncated packets will have their IPv4 total length field rewritten to match
the actual packet length
.sp 1
\fBdel\fP
Delete the packet
.TP
.BR \--skipl2broadcast
Skip rewriting broadcast/multicast Layer 2 addresses.
.sp
By default, editing Layer 2 addresses will rewrite 
broadcast and multicast MAC addresses.	Setting this flag
will keep broadcast/multicast MAC addresses from being rewritten.
.TP
.BR \--dlt "=\fIstring\fP"
Override output DLT encapsulation.
This option may appear up to 1 times.
.sp
By default, no DLT (data link type) conversion will be made.  
To change the DLT type of the output pcap, select one of the following values:
.sp 1
\fBenet\fP
Ethernet aka DLT_EN10MB
.sp 1
\fBhdlc\fP
Cisco HDLC aka DLT_C_HDLC
.sp 1
\fBuser\fP
User specified Layer 2 header and DLT type
.br
.TP
.BR \--enet-dmac "=\fIstring\fP"
Override destination ethernet MAC addresses.
This option may appear up to 1 times.
.sp
Takes a pair of comma deliminated ethernet MAC addresses which
will replace the destination MAC address of outbound packets.
The first MAC address will be used for the server to client traffic
and the optional second MAC address will be used for the client
to server traffic.

Example:
.nf
    \--enet-dmac=00:12:13:14:15:16,00:22:33:44:55:66
.fi
.TP
.BR \--enet-smac "=\fIstring\fP"
Override source ethernet MAC addresses.
This option may appear up to 1 times.
.sp
Takes a pair of comma deliminated ethernet MAC addresses which
will replace the source MAC address of outbound packets.
The first MAC address will be used for the server to client traffic
and the optional second MAC address will be used for the client 
to server traffic.

Example:
.nf
    \--enet-smac=00:12:13:14:15:16,00:22:33:44:55:66
.fi
.TP
.BR \--enet-vlan "=\fIstring\fP"
Specify ethernet 802.1q VLAN tag mode.
This option may appear up to 1 times.
.sp
Allows you to rewrite ethernet frames to add a 802.1q header to standard 802.3
ethernet headers or remove the 802.1q VLAN tag information.
.sp 1
\fBadd\fP
Rewrites the existing 802.3 ethernet header as an 802.1q VLAN header
.sp 1
\fBdel\fP
Rewrites the existing 802.1q VLAN header as an 802.3 ethernet header
.TP
.BR \--enet-vlan-tag "=\fInumber\fP"
Specify the new ethernet 802.1q VLAN tag value.
This option may appear up to 1 times.
This option must appear in combination with the following options:
enet-vlan.
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 4095
.fi
.in -4
.sp

.TP
.BR \--enet-vlan-cfi "=\fInumber\fP"
Specify the ethernet 802.1q VLAN CFI value.
This option may appear up to 1 times.
This option must appear in combination with the following options:
enet-vlan.
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 1
.fi
.in -4
.sp

.TP
.BR \--enet-vlan-pri "=\fInumber\fP"
Specify the ethernet 802.1q VLAN priority.
This option may appear up to 1 times.
This option must appear in combination with the following options:
enet-vlan.
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 7
.fi
.in -4
.sp

.TP
.BR \--hdlc-control "=\fInumber\fP"
Specify HDLC control value.
This option may appear up to 1 times.
This option takes an integer number as its argument.
.sp
The Cisco HDLC header has a 1 byte "control" field.  Apparently this should 
always be 0, but if you can use any 1 byte value.
.TP
.BR \--hdlc-address "=\fInumber\fP"
Specify HDLC address.
This option may appear up to 1 times.
This option takes an integer number as its argument.
.sp
The Cisco HDLC header has a 1 byte "address" field which has two valid 
values:
.sp 1
\fB0x0F\fP
Unicast
.sp 1
\fB0xBF\fP
Broadcast
.br
You can however specify any single byte value.
.TP
.BR \--user-dlt "=\fInumber\fP"
Set output file DLT type.
This option may appear up to 1 times.
This option takes an integer number as its argument.
.sp
Set the DLT value of the output pcap file.
.TP
.BR \--user-dlink "=\fIstring\fP"
Rewrite Data-Link layer with user specified data.
This option may appear up to 2 times.
.sp
Provide a series of comma deliminated hex values which will be
used to rewrite or create the Layer 2 header of the packets.
The first instance of this argument will rewrite both server
and client traffic, but if this argument is specified a second
time, it will be used for the client traffic.

Example:
.nf
    \--user-dlink=01,02,03,04,05,06,00,1A,2B,3C,4D,5E,6F,08,00
.fi
.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 \-T " \fIstring\fP, " \--timer "=" \fIstring\fP
Select packet timing mode: select, ioport, rdtsc, gtod, nano, abstime.
This option may appear up to 1 times.
The default \fIstring\fP for this option is:
.ti +4
 gtod
.sp
Allows you to select the packet timing method to use:
.sp
.IR "nano"
- Use nanosleep() API
.sp
.IR "select"
- Use select() API
.sp
.IR "ioport"
- Write to the i386 IO Port 0x80
.sp
.IR "rdtsc  "
- Use the x86/x86_64/PPC RDTSC
.sp
.IR "gtod [default]"
- Use a gettimeofday() loop
.sp
.IR "abstime"
- Use OS X's AbsoluteTime API
.br

.TP
.BR \--sleep-accel "=\fInumber\fP"
Reduce the amount of time to sleep by specified usec.
This option takes an integer number as its argument.
The default \fInumber\fP for this option is:
.ti +4
 0
.sp
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.
.TP
.BR \--rdtsc-clicks "=\fInumber\fP"
Specify the RDTSC clicks/usec.
This option may appear up to 1 times.
This option takes an integer number as its argument.
The default \fInumber\fP for this option is:
.ti +4
 0
.sp
Override the calculated number of RDTSC clicks/usec which is often the speed of the 
CPU in Mhz.  Only useful if you specified \fB--timer=rdtsc\fP
.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.

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.
.SH AUTHOR
Copyright 2000-2008 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.