tcpreplay(1) User Commands tcpreplay(1)NAMEtcpreplay - Replay network traffic stored in pcap files
SYNOPSIStcpreplay [-flags] [-flag [value]] [--option-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
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://tcpre‐
play.appneta.com
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 ver‐
bosity level for debugging output. Higher numbers increase ver‐
bosity.
-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, gtod, nano. 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
gtod [default] - Use a gettimeofday() loop
--maxsleep=number
Sleep for no more then X milliseconds between packets. This
option takes an integer number as its argument. The default
number for this option is:
0
Set a limit for the maximum number of milliseconds that tcpre‐
play will sleep between packets. Effectively prevents long
delays between packets without effecting the majority of pack‐
ets. Default is disabled.
-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 pack‐
ets are decoded. By default, -n and -l are used. Be sure to
quote the arguments like: -A "-axxx" so that they are not inter‐
preted by tcpreplay. Please see the tcpdump(1) man page for a
complete list of options.
-K, --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 with‐
out --loop. This option also suppresses flow statistics collec‐
tion for every iteration, which can significantly reduce memory
usage. Flow statistics are predicted based on options supplied
and statistics collected from the first loop iteration.
-c string, --cachefile=string
Split traffic via a tcpprep cache file. This option may appear
up to 1 times. This option must appear in combination with the
following options: intf2. This option must not appear in combi‐
nation with any of the following options: dualfile.
If you have a pcap file you would like to use to send bi-direc‐
tional traffic through a device (firewall, router, IDS, etc)
then using tcpprep you can create a cachefile which tcpreplay
will use to split the traffic across two network interfaces.
-2, --dualfile
Replay two files at a time from a network tap. This option may
appear up to 1 times. This option must appear in combination
with the following options: intf2. This option must not appear
in combination with any of the following options: cachefile.
If you captured network traffic using a network tap, then you
can end up with two pcap files- one for each direction. This
option will replay these two files at the same time, one on each
interface and inter-mix them using the timestamps in each.
-i string, --intf1=string
Client to server/RX/primary traffic output interface. This
option may appear up to 1 times.
Required network interface used to send either all traffic or
traffic which is marked as 'primary' via tcpprep. Primary traf‐
fic is usually client-to-server or inbound (RX) on khial virtual
interfaces.
-I string, --intf2=string
Server to client/TX/secondary traffic output interface. This
option may appear up to 1 times.
Optional network interface used to send traffic which is marked
as 'secondary' via tcpprep. Secondary traffic is usually
server-to-client or outbound (TX) on khial virtual interfaces.
Generally, it only makes sense to use this option with
--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 argu‐
ment. The value of number is constrained to being:
greater than or equal to 0
The default number for this option is:
1
--loopdelay-ms=number
Delay between loops in milliseconds. This option must appear in
combination with the following options: loop. This option takes
an integer number as its argument. The value of number is con‐
strained to being:
greater than or equal to 0
The default number for this option is:
0
--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 argu‐
ment. 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.
--duration=number
Limit the number of seconds to send. This option may appear up
to 1 times. This option takes an integer number as its argu‐
ment. 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 seconds to transmit.
-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 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, top‐
speed. 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, multi‐
plier, 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.
--unique-ip
Modify IP addresses each loop iteration to generate unique
flows.
Ensure IPv4 and IPv6 packets will be unique for each --loop
iteration. This is done in a way that will not alter packet
CRC, and therefore will genrally not affect performance. This
option will significantly increase the flows/sec over generated
over multiple loop iterations.
--netmap
Write packets directly to netmap enabled network adapter.
This feature will detect netmap capable network drivers on Linux
and BSD systems. If detected, the network driver is bypassed for
the execution duration, and network buffers will be written to
directly. This will allow you to achieve full line rates on com‐
modity network adapters, similar to rates achieved by commercial
network traffic generators. Note that bypassing the network
driver will disrupt other applications connected through the
test interface. See INSTALL for more information.
This feature can also be enabled by specifying an interface as
'netmap:<intf>' or 'vale:<intf>. For example 'netmap:eth0' spec‐
ifies netmap over interface eth0.
--nm-delay=number
Netmap startup delay. This option must appear in combination
with the following options: netmap. This option takes an inte‐
ger number as its argument. The default number for this option
is:
4
Number of seconds to delay after netmap is loaded. Required to
ensure interfaces are fully up before netmap transmit. Requires
netmap option. Default is 4 seconds.
--no-flow-stats
Suppress printing and tracking flow count, rates and expira‐
tions.
Suppress the collection and printing of flow statistics. This
option may improve performance when not using --preload-pcap
option, otherwise its only function is to suppress printing.
The flow feature will track and print statistics of the flows
being sent. A flow is loosely defined as a unique combination
of a 5-tuple, i.e. source IP, destination IP, source port, des‐
tination port and protocol.
If --loop is specified, the flows from one iteration to the next
will not be unique, unless the packets are altered. Use
--unique-ip or tcpreplay-edit to alter packets between itera‐
tions.
--flow-expiry=number
Number of inactive seconds before a flow is considered expired.
This option must not appear in combination with any of the fol‐
lowing options: no-flow-stats. 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:
0
This option will track and report flow expirations based on the
flow idle times. The timestamps within the pcap file are used to
determine the expiry, not the actual timestamp of the packets
are replayed. For example, a value of 30 suggests that if no
traffic is seen on a flow for 30 seconds, any subsequent traffic
would be considered a new flow, and thereby will increment the
flows and flows per second (fps) statistics.
This option can be used to optimize flow timeout settings for
flow products. Setting the timeout low may lead to flows being
dropped when in fact the flow is simply slow to respond. Config‐
uring your flow timeouts too high may increase resources
required by your flow product.
Note that using this option while replaying at higher than orig‐
inal speeds can lead to inflated flows and fps counts.
Default is 0 (no expiry) and a typical value is 30-120 seconds.
-P, --pid
Print the PID of tcpreplay at startup.
--quick-tx
Write packets directly to an interface via Quick_TX module.
This feature will detect detect the presence of the Quick TX
module on Linux systems. If detected, tcpreplay packets will
bypass the network stack and will be written to the network
driver via the Quick TX module. This will allow you to achieve
full line rates on commodity network adapters, similar to rates
achieved by commercial network traffic generators.
Note that unlike netmap, Quick TX does not bypass the network
driver and therefore is less disruptive. Yet it can achieve TX
rates comparble netmap. Quick TX is distributed with Tcpreplay
and does not require full kernel source in order to be
installed. See INSTALL for more information.
This feature can also be enabled by specifying an interface as
'qtx:<intf>'. For example 'qtx:eth0' specifies Quick TX over
interface eth0.
--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
Pass the extended usage information through a pager.
--save-opts [=cfgfile]
Save the option state to cfgfile. The default is the last con‐
figuration file listed in the OPTION PRESETS section, below.
The command will exit after updating the config file.
--load-opts=cfgfile, --no-load-opts
Load options from cfgfile. The no-load-opts form will disable
the loading of earlier config/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 load‐
ing 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.
FILES
See OPTION PRESETS for configuration files.
EXIT STATUS
One of the following exit values will be returned:
0 (EXIT_SUCCESS)
Successful program execution.
1 (EXIT_FAILURE)
The operation failed or the command syntax was not valid.
66 (EX_NOINPUT)
A specified configuration file could not be loaded.
70 (EX_SOFTWARE)
libopts had an internal operational error. Please report it to
autogen-users@lists.sourceforge.net. Thank you.
AUTHORS
Copyright 2013-2014 Fred Klassen - AppNeta Copyright 2000-2012 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.appneta.com/
COPYRIGHT
Copyright (C) 2000-2014 Aaron Turner and Fred Klassen all rights
reserved. This program is released under the terms of the GNU General
Public License, version 3 or later.
BUGS
Please send bug reports to: tcpreplay-users@lists.sourceforge.net
NOTES
This manual page was AutoGen-erated from the tcpreplay option defini‐
tions.
tcpreplay 11 Jan 2016 tcpreplay(1)
