DOKK / manpages / debian 12 / anytun / anytun-config.8.en

anytun-config - anycast tunneling configuration utility


[ -h|--help ]
[ -L|--log <target>:<level>[,<param1>[,<param2>[..]]]
[ -U|--debug ]
[ -r|--remote-host <hostname|ip> ]
[ -o|--remote-port <port> ]
[ -4|--ipv4-only ]
[ -6|--ipv6-only ]
[ -R|--route <net>/<prefix length> ]
[ -m|--mux <mux-id> ]
[ -w|--window-size <window size> ]
[ -k|--kd-prf <kd-prf type> ]
[ -e|--role <role> ]
[ -E|--passphrase <pass phrase> ]
[ -K|--key <master key> ]
[ -A|--salt <master salt> ]

anytun-config writes routing/connection table entries, that can be read by anytun-controld.

-L, --log <target>:<level>[,<param1>[,<param2>[..]]]

add log target to logging system. This can be invoked several times in order to log to different targets at the same time. Every target hast its own log level which is a number between 0 and 5. Where 0 means disabling log and 5 means debug messages are enabled.

The file target can be used more the once with different levels. If no target is provided at the command line a single target with the config syslog:3,anytun-config,daemon is added.

The following targets are supported:


log to syslog daemon, parameters <level>[,<logname>[,<facility>]]


log to file, parameters <level>[,<path>]


log to standard output, parameters <level>


log to standard error, parameters <level>

-U, --debug

This option instructs Anytun to run in debug mode. It implicits -D (don’t daemonize) and adds a log target with the configuration stdout:5 (logging with maximum level). In future releases there might be additional output when this option is supplied.

-r, --remote-host <hostname|ip>

This option can be used to specify the remote tunnel endpoint. In case of anycast tunnel endpoints, the anycast IP address has to be used. If you do not specify an address, it is automatically determined after receiving the first data packet.

-o, --remote-port <port>

The UDP port used for payload data by the remote host (specified with -p on the remote host). If you do not specify a port, it is automatically determined after receiving the first data packet.

-4, --ipv4-only

Resolv to IPv4 addresses only. The default is to resolv both IPv4 and IPv6 addresses.

-6, --ipv6-only

Resolv to IPv6 addresses only. The default is to resolv both IPv4 and IPv6 addresses.

-R, --route <net>/<prefix length>

add a route to connection. This can be invoked several times.

-m, --mux <mux-id>

the multiplex id to use. default: 0

-w, --window-size <window size>

seqence window size

Sometimes, packets arrive out of order on the receiver side. This option defines the size of a list of received packets' sequence numbers. If, according to this list, a received packet has been previously received or has been transmitted in the past, and is therefore not in the list anymore, this is interpreted as a replay attack and the packet is dropped. A value of 0 deactivates this list and, as a consequence, the replay protection employed by filtering packets according to their secuence number. By default the sequence window is disabled and therefore a window size of 0 is used.

-k, --kd—prf <kd-prf type>

key derivation pseudo random function

The pseudo random function which is used for calculating the session keys and session salt.

Possible values:


no random function, keys and salt are set to 0..00


AES in counter mode with 128 Bits, default value


AES in counter mode with 128 Bits


AES in counter mode with 192 Bits


AES in counter mode with 256 Bits

-e, --role <role>

SATP uses different session keys for inbound and outbound traffic. The role parameter is used to determine which keys to use for outbound or inbound packets. On both sides of a vpn connection different roles have to be used. Possible values are left and right. You may also use alice or server as a replacement for left and bob or client as a replacement for right. By default left is used.

-E, --passphrase <pass phrase>

This passphrase is used to generate the master key and master salt. For the master key the last n bits of the SHA256 digest of the passphrase (where n is the length of the master key in bits) is used. The master salt gets generated with the SHA1 digest. You may force a specific key and or salt by using --key and --salt.

-K, --key <master key>

master key to use for key derivation

Master key in hexadecimal notation, e.g. 01a2b3c4d5e6f708a9b0cadbecfd0fa1, with a mandatory length of 32, 48 or 64 characters (128, 192 or 256 bits).

-A, --salt <master salt>

master salt to use for key derivation

Master salt in hexadecimal notation, e.g. 01a2b3c4d5e6f708a9b0cadbecfd, with a mandatory length of 28 characters (14 bytes).

Add a client with Connection ID (Mux) 12 and add 2 Routes to this client

# anytun-config -w 0 -m 12 -K 0123456789ABCDEFFEDCBA9876543210 -A 0123456789ABCDDCBA9876543210 \

-R -R -e server >> routingtable

Most likely there are some bugs in Anytun. If you find a bug, please let the developers know at Of course, patches are preferred.

anytun(8), anytun-controld(8), anytun-showtables(8)

Othmar Gsenger <> Erwin Nindl <> Christian Pointner <>

Main web site:

Copyright (C) 2007-2014 Markus Grüneis, Othmar Gsenger, Erwin Nindl and Christian Pointner. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or any later version.