Provided by: tcpreplay_4.4.4-1build2_amd64 
NAME
tcpreplay-edit - Replay network traffic stored in pcap files
SYNOPSIS
tcpreplay-edit [-flags] [-flag [value]] [--option-name[[=| ]value]] <pcap_file(s)> | <pcap_dir(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://tcpreplay.appneta.com
OPTIONS
-r string, --portmap=string Rewrite TCP/UDP ports. This option may appear up to 9999 times.
Specify a list of comma delimited port mappings 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.
Examples:
--portmap=80:8000 --portmap=8080:80 # 80->8000 and 8080->80
--portmap=8000,8080,88888:80 # 3 different ports become 80
--portmap=8000-8999:80 # ports 8000 to 8999 become 80
-s number, --seed=number Randomize src/dst IPv4/v6 addresses w/ given seed. This option may appear up to
1 times. This option must not appear in combination with any of the following options: fuzz-seed. This
option takes an integer number as its argument.
Causes the source and destination IPv4/v6 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.
-N string, --pnat=string Rewrite IPv4/v6 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.
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
rewritten using the second netblock as a mask against the high order bits.
IPv4 Example:
--pnat=192.168.0.0/16:10.77.0.0/16,172.16.0.0/12:10.1.0.0/24
IPv6 Example:
--pnat=[2001:db8::/32]:[dead::/16],[2001:db8::/32]:[::ffff:0:0/96]
-S string, --srcipmap=string Rewrite source IPv4/v6 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.
Works just like the --pnat option, but only affects the source IP addresses in the IPv4/v6 header.
-D string, --dstipmap=string Rewrite destination IPv4/v6 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.
Works just like the --pnat option, but only affects the destination IP addresses in the IPv4/v6 header.
-e string, --endpoints=string 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.
Takes a pair of colon delimited IPv4/v6 addresses which will be used to rewrite all traffic to appear to
be between the two IP addresses.
IPv4 Example:
--endpoints=172.16.0.1:172.16.0.2
IPv6 Example:
--endpoints=[2001:db8::dead:beef]:[::ffff:0:0:ac:f:0:2]
--tcp-sequence=number Change TCP Sequence (and ACK) numbers /w given seed. 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:
0
Change all TCP sequence numbers, and related sequence-acknowledgement numbers. They will be shifted by a
random amount based on the provided seed.
-b, --skipbroadcast Skip rewriting broadcast/multicast IPv4/v6 addresses.
By default --seed, --pnat and --endpoints will rewrite broadcast and multicast IPv4/v6 and MAC
addresses. Setting this flag will keep broadcast/multicast IPv4/v6 and MAC addresses from being
rewritten.
-C, --fixcsum Force recalculation of IPv4/TCP/UDP header checksums.
Causes each IPv4/v6 packet to have their checksums recalculated and fixed. Automatically enabled for
packets modified with --seed, --pnat, --endpoints or --fixlen.
-m number, --mtu=number 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 number is constrained to being:
in the range 1 through MAX_SNAPLEN
Override the default 1500 byte MTU size for determining the maximum padding length (--fixlen=pad) or when
truncating (--mtu-trunc).
--mtu-trunc Truncate packets larger then specified MTU. This option may appear up to 1 times.
Similar to --fixlen, this option will truncate data in packets from Layer 3 and above to be no larger
then the MTU.
-E, --efcs Remove Ethernet checksums (FCS) from end of frames.
Note, this option is pretty dangerous! We do not actually check to see if a FCS actually exists in the
frame, we just blindly delete the last 4 bytes. Hence, you should only use this if you know know that
your OS provides the FCS when reading raw packets.
--ttl=string Modify the IPv4/v6 TTL/Hop Limit.
Allows you to modify the TTL/Hop Limit of all the IPv4/v6 packets. Specify a number to hard-code the
value or +/-value to increase or decrease by the value provided (limited to 1-255).
Examples:
--ttl=10
--ttl=+7
--ttl=-64
--tos=number Set the IPv4 TOS/DiffServ/ECN byte. 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 255
Allows you to override the TOS (also known as DiffServ/ECN) value in IPv4.
--tclass=number Set the IPv6 Traffic Class byte. 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 255
Allows you to override the IPv6 Traffic Class field.
--flowlabel=number Set the IPv6 Flow Label. 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 1048575
Allows you to override the 20bit IPv6 Flow Label field. Has no effect on IPv4 packets.
-F string, --fixlen=string Pad or truncate packet data to match header length. This option may appear up
to 1 times.
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/v6 header or rewrite
the IP header total length to reflect the stored packet length.
pad Truncated packets will be padded out so that the packet length matches the IPv4 total length
trunc Truncated packets will have their IPv4 total length field rewritten to match the actual packet
length
del Delete the packet
--fuzz-seed=number Fuzz 1 in X packets. Edit bytes, length, or emulate packet drop. 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 fuzzing was designed as to test layer 7 protocols such as voip protocols. It modifies randomly 1
out of X packets (where X = --fuzz-factor) in order for stateful protocols to cover more of their code.
The random fuzzing actions focus on data start and end because it often is the part of the data
application protocols base their decisions on.
Possible fuzzing actions list:
* drop packet
* reduce packet size
* edit packet Bytes:
* Not all Bytes have the same probability of appearance in real life.
Replace with 0x00, 0xFF, or a random byte with equal likelihood.
* Not all Bytes have the same significance in a packet.
Replace the start, the end, or the middle of the packet with equal likelihood.
* do nothing (7 out of 8 packets)
--fuzz-factor=number Set the Fuzz 1 in X packet ratio (default 1 in 8 packets). This option must appear
in combination with the following options: fuzz-seed. 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:
8
Sets the ratio of for --fuzz-seed option. By default this value is 8, which means 1 in 8 packets are
modified by fuzzing. Note that this ratio is based on the random number generated by the supplied fuzz
seed. Therefore by default you cannot expect that exactly every eighth packet will be modified.
--skipl2broadcast Skip rewriting broadcast/multicast Layer 2 addresses.
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.
--dlt=string Override output DLT encapsulation. This option may appear up to 1 times.
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:
enet Ethernet aka DLT_EN10MB
hdlc Cisco HDLC aka DLT_C_HDLC
jnpr_eth Juniper Ethernet DLT_C_JNPR_ETHER
pppserial PPP Serial aka DLT_PPP_SERIAL
user User specified Layer 2 header and DLT type
--enet-dmac=string Override destination ethernet MAC addresses. This option may appear up to 1 times.
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:
--enet-dmac=00:12:13:14:15:16,00:22:33:44:55:66
--enet-smac=string Override source ethernet MAC addresses. This option may appear up to 1 times.
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:
--enet-smac=00:12:13:14:15:16,00:22:33:44:55:66
--enet-subsmac=string Substitute MAC addresses. This option may appear up to 9999 times.
Allows you to rewrite ethernet MAC addresses of packets. It takes comma delimited pair or MACs address
and rewrites all occurrences of the first MAC with the value of the second MAC. Example:
--enet-subsmac=00:12:13:14:15:16,00:22:33:44:55:66
--enet-mac-seed=number Randomize MAC addresses. This option may appear up to 1 times. This option must
not appear in combination with any of the following options: enet-smac, enet-dmac, enet-subsmac. This
option takes an integer number as its argument.
Allows you to randomize ethernet MAC addresses of packets, mostly like what --seed option does for
IPv4/IPv6 addresses.
--enet-mac-seed-keep-bytes=number Randomize MAC addresses. This option may appear up to 1 times. This
option must appear in combination with the following options: enet-mac-seed. This option takes an
integer number as its argument. The value of number is constrained to being:
in the range 1 through 6
Keep some bytes untouched when usinging --enet-mac-seed option.
--enet-vlan=string Specify ethernet 802.1q VLAN tag mode. This option may appear up to 1 times.
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.
add Adds an 802.1q VLAN header to the existing 802.3 ethernet header. If a VLAN header already exists, a
new VLAN header is added outside of the existing header.
Note that you will be allowed to run this option multiple times to create more than 2 VLAN headers,
however those packets will be valid. At most you should have 2 X 802.1q VLAN tags, or outer an 802.1ad
and an inner 802.1q VLAN tag.
del Rewrites the existing 802.1q VLAN header as an 802.3 ethernet header
--enet-vlan-tag=number 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 number is constrained to being:
in the range 0 through 4095
--enet-vlan-cfi=number 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 number is constrained to being:
in the range 0 through 1
--enet-vlan-pri=number 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 number is constrained to being:
in the range 0 through 7
--enet-vlan-proto=string Specify VLAN tag protocol 802.1q or 802.1ad. This option may appear up to 1
times.
Allows you to specify the protocol of the added VLAN tags.
802.1q Specifies that 802.1q VLAN headers are to be added. This is the default.
802.1ad Specifies that 802.1ad Q-in-Q VLAN headers are to be added. To make valid packets, input packets
must already have 802.1q VLAN headers.
--hdlc-control=number Specify HDLC control value. This option may appear up to 1 times. This option
takes an integer number as its argument.
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.
--hdlc-address=number Specify HDLC address. This option may appear up to 1 times. This option takes an
integer number as its argument.
The Cisco HDLC header has a 1 byte "address" field which has two valid values:
0x0F Unicast
0xBF Broadcast
You can however specify any single byte value.
--user-dlt=number Set output file DLT type. This option may appear up to 1 times. This option takes an
integer number as its argument.
Set the DLT value of the output pcap file.
--user-dlink=string Rewrite Data-Link layer with user specified data. This option may appear up to 2
times.
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:
--user-dlink=01,02,03,04,05,06,00,1A,2B,3C,4D,5E,6F,08,00
-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, 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 tcpreplay will sleep between packets.
Effectively prevents long delays between packets without effecting the majority of packets. 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 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, --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.
This option also suppresses flow statistics collection 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 combination with any of the following options: dualfile.
If you have a pcap file you would like to use to send bi-directional 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 traffic 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 argument. 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 constrained 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 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.
--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 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
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 string, --pps=string 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.
Specify a value to regulate the packet replay to a specific packet-per-second rate. Examples:
200 will replay traffic at 200 packets per second
0.25 will replay traffic at 15 packets per minute
-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.
--unique-ip Modify IP addresses each loop iteration to generate unique flows. This option must appear in
combination with the following options: loop. This option must not appear in combination with any of the
following options: seed, fuzz-seed.
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 generally not affect performance. This option will significantly
increase the flows/sec over generated over multiple loop iterations.
--unique-ip-loops=string Number of times to loop before assigning new unique ip. This option may appear
up to 1 times. This option must appear in combination with the following options: unique-ip.
Number of --loop iterations before a new unique IP is assigned. Default is 1. Assumes both --loop and
--unique-ip.
--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 commodity 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' specifies netmap over interface eth0.
--nm-delay=number Netmap startup delay. This option takes an integer number as its argument. The
default number for this option is:
10
Number of seconds to delay after netmap is loaded. Required to ensure interfaces are fully up before
netmap transmit. Requires netmap option. Default is 10 seconds.
--no-flow-stats Suppress printing and tracking flow count, rates and expirations.
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, destination 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 iterations.
--flow-expiry=number Number of inactive seconds before a flow is considered expired. This option must
not appear in combination with any of the following 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. Configuring your flow
timeouts too high may increase resources required by your flow product.
Note that using this option while replaying at higher than original 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.
--stats=number Print statistics every X seconds, or every loop if '0'. This option takes an integer
number as its argument. The value of number is constrained to being:
greater than or equal to 0
Note that timed delays are 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 configuration 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 loading values from
configuration ("RC" or ".INI") file(s). The homerc file is "$$/", unless that is a directory. In
that case, the file ".tcpreplay-editrc" 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 2013-2022 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) 2000-2022 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-edit option definitions.
tcpreplay 11 Jun 2023 tcpreplay-edit(1)