3 .\" Manual page created by:
5 .\" Guus Sliepen <guus@tinc-vpn.org>
9 .Nd tinc daemon configuration
13 .Pa @sysconfdir@/tinc/
14 directory contain runtime and security information for the tinc daemon.
17 It is perfectly ok for you to run more than one tinc daemon.
18 However, in its default form,
19 you will soon notice that you can't use two different configuration files without the
24 We have thought of another way of dealing with this: network names.
25 This means that you call
29 option, which will assign a name to this daemon.
32 The effect of this is that the daemon will set its configuration root to
33 .Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa / ,
36 is your argument to the
39 You'll notice that messages appear in syslog as coming from
40 .Nm tincd. Ns Ar NETNAME .
43 However, it is not strictly necessary that you call tinc with the
46 In this case, the network name would just be empty,
47 and it will be used as such.
49 now looks for files in
50 .Pa @sysconfdir@/tinc/ ,
52 .Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa / ;
53 the configuration file should be
54 .Pa @sysconfdir@/tinc/tinc.conf ,
55 and the host configuration files are now expected to be in
56 .Pa @sysconfdir@/tinc/hosts/ .
59 But it is highly recommended that you use this feature of
61 because it will be so much clearer whom your daemon talks to.
62 Hence, we will assume that you use it.
65 Each tinc daemon should have a name that is unique in the network which it will be part of.
66 The name will be used by other tinc daemons for identification.
67 The name has to be declared in the
68 .Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /tinc.conf
73 choose something that will give unique and easy to remember names to your tinc daemon(s).
74 You could try things like hostnames, owner surnames or location names.
76 .Sh PUBLIC/PRIVATE KEYS
79 to generate public/private keypairs.
80 It will generate two keys.
81 The private key should be stored in a separate file
82 .Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /rsa_key.priv
85 stands for the network (see
88 The public key should be stored in the host configuration file
89 .Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /hosts/ Ns Va NAME
92 stands for the name of the local tinc daemon (see
95 .Sh SERVER CONFIGURATION
96 The server configuration of the daemon is done in the file
97 .Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /tinc.conf .
98 This file consists of comments (lines started with a
100 or assignments in the form of:
103 .Va Variable Li = Ar Value .
106 The variable names are case insensitive, and any spaces, tabs,
107 newlines and carriage returns are ignored.
108 Note: it is not required that you put in the
110 sign, but doing so improves readability.
111 If you leave it out, remember to replace it with at least one space character.
114 The server configuration is complemented with host specific configuration (see the next section).
115 Although all configuration options for the local host listed in this document can also be put in
116 .Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /tinc.conf ,
117 it is recommended to put host specific configuration options in the host configuration file,
118 as this makes it easy to exchange with other nodes.
121 Here are all valid variables, listed in alphabetical order.
122 The default value is given between parentheses.
123 .Bl -tag -width indent
125 .It Va AddressFamily Li = ipv4 | ipv6 | any Pq any
126 This option affects the address family of listening and outgoing sockets.
129 is selected, then depending on the operating system both IPv4 and IPv6 or just
130 IPv6 listening sockets will be created.
132 .It Va BindToAddress Li = Ar address Bq experimental
133 If your computer has more than one IPv4 or IPv6 address,
135 will by default listen on all of them for incoming connections.
136 It is possible to bind only to a single address with this variable.
139 This option may not work on all platforms.
141 .It Va BindToInterface Li = Ar interface Bq experimental
142 If your computer has more than one network interface,
144 will by default listen on all of them for incoming connections.
145 It is possible to bind only to a single interface with this variable.
148 This option may not work on all platforms.
150 .It Va ConnectTo Li = Ar name
151 Specifies which other tinc daemon to connect to on startup.
154 variables may be specified,
155 in which case outgoing connections to each specified tinc daemon are made.
156 The names should be known to this tinc daemon
157 (i.e., there should be a host configuration file for the name on the
162 If you don't specify a host with
165 won't try to connect to other daemons at all,
166 and will instead just listen for incoming connections.
168 .It Va Device Li = Ar device Po Pa /dev/tap0 , Pa /dev/net/tun No or other depending on platform Pc
169 The virtual network device to use.
171 will automatically detect what kind of device it is.
172 Note that you can only use one device per daemon.
177 The info pages of the tinc package contain more information
178 about configuring the virtual network device.
180 .It Va DeviceType Li = tun | tunnohead | tunifhead | tap Po only supported on BSD platforms Pc
181 The type of the virtual network device.
182 Tinc will normally automatically select the right type, and this option should not be used.
183 However, in case tinc does not seem to correctly interpret packets received from the virtual network device,
184 using this option might help.
185 .Bl -tag -width indent
189 Depending on the platform, this can either be with or without an address family header (see below).
192 Set type to tun without an address family header.
193 Tinc will expect packets read from the virtual network device to start with an IP header.
194 On some platforms IPv6 packets cannot be read from or written to the device in this mode.
197 Set type to tun with an address family header.
198 Tinc will expect packets read from the virtual network device
199 to start with a four byte header containing the address family,
200 followed by an IP header.
201 This mode should support both IPv4 and IPv6 packets.
205 Tinc will expect packets read from the virtual network device
206 to start with an Ethernet header.
209 .It Va DirectOnly Li = yes | no Po no Pc Bq experimental
210 When this option is enabled, packets that cannot be sent directly to the destination node,
211 but which would have to be forwarded by an intermediate node, are dropped instead.
212 When combined with the IndirectData option,
213 packets for nodes for which we do not have a meta connection with are also dropped.
215 .It Va Forwarding Li = off | internal | kernel Po internal Pc Bq experimental
216 This option selects the way indirect packets are forwarded.
217 .Bl -tag -width indent
220 Incoming packets that are not meant for the local node,
221 but which should be forwarded to another node, are dropped.
224 Incoming packets that are meant for another node are forwarded by tinc internally.
227 This is the default mode, and unless you really know you need another forwarding mode, don't change it.
230 Incoming packets are always sent to the TUN/TAP device, even if the packets are not for the local node.
231 This is less efficient, but allows the kernel to apply its routing and firewall rules on them,
232 and can also help debugging.
235 .It Va GraphDumpFile Li = Ar filename Bq experimental
236 If this option is present,
238 will dump the current network graph to the file
240 every minute, unless there were no changes to the graph.
241 The file is in a format that can be read by graphviz tools.
244 starts with a pipe symbol |,
245 then the rest of the filename is interpreted as a shell command
246 that is executed, the graph is then sent to stdin.
248 .It Va Hostnames Li = yes | no Pq no
249 This option selects whether IP addresses (both real and on the VPN) should
250 be resolved. Since DNS lookups are blocking, it might affect tinc's
251 efficiency, even stopping the daemon for a few seconds every time it does
252 a lookup if your DNS server is not responding.
255 This does not affect resolving hostnames to IP addresses from the
256 host configuration files.
258 .It Va IffOneQueue Li = yes | no Po no Pc Bq experimental
259 (Linux only) Set IFF_ONE_QUEUE flag on TUN/TAP devices.
261 .It Va Interface Li = Ar interface
262 Defines the name of the interface corresponding to the virtual network device.
263 Depending on the operating system and the type of device this may or may not actually set the name of the interface.
264 Under Windows, this variable is used to select which network interface will be used.
267 this variable is almost always already correctly set.
269 .It Va KeyExpire Li = Ar seconds Pq 3600
270 This option controls the period the encryption keys used to encrypt the data are valid.
271 It is common practice to change keys at regular intervals to make it even harder for crackers,
272 even though it is thought to be nearly impossible to crack a single key.
274 .It Va MACExpire Li = Ar seconds Pq 600
275 This option controls the amount of time MAC addresses are kept before they are removed.
276 This only has effect when
281 .It Va MaxTimeout Li = Ar seconds Pq 900
282 This is the maximum delay before trying to reconnect to other tinc daemons.
284 .It Va Mode Li = router | switch | hub Pq router
285 This option selects the way packets are routed to other daemons.
286 .Bl -tag -width indent
291 variables in the host configuration files will be used to form a routing table.
292 Only unicast packets of routable protocols (IPv4 and IPv6) are supported in this mode.
295 This is the default mode, and unless you really know you need another mode, don't change it.
298 In this mode the MAC addresses of the packets on the VPN will be used to
299 dynamically create a routing table just like an Ethernet switch does.
300 Unicast, multicast and broadcast packets of every protocol that runs over Ethernet are supported in this mode
301 at the cost of frequent broadcast ARP requests and routing table updates.
304 This mode is primarily useful if you want to bridge Ethernet segments.
307 This mode is almost the same as the switch mode, but instead
308 every packet will be broadcast to the other daemons
309 while no routing table is managed.
312 .It Va Name Li = Ar name Bq required
313 This is the name which identifies this tinc daemon.
314 It must be unique for the virtual private network this daemon will connect to.
316 .It Va PingInterval Li = Ar seconds Pq 60
317 The number of seconds of inactivity that
319 will wait before sending a probe to the other end.
321 .It Va PingTimeout Li = Ar seconds Pq 5
322 The number of seconds to wait for a response to pings or to allow meta
323 connections to block. If the other end doesn't respond within this time,
324 the connection is terminated,
325 and the others will be notified of this.
327 .It Va PriorityInheritance Li = yes | no Po no Pc Bq experimental
328 When this option is enabled the value of the TOS field of tunneled IPv4 packets
329 will be inherited by the UDP packets that are sent out.
331 .It Va PrivateKey Li = Ar key Bq obsolete
332 The private RSA key of this tinc daemon.
333 It will allow this tinc daemon to authenticate itself to other daemons.
335 .It Va PrivateKeyFile Li = Ar filename Po Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /rsa_key.priv Pc
336 The file in which the private RSA key of this tinc daemon resides.
337 Note that there must be exactly one of
341 specified in the configuration file.
343 .It Va ProcessPriority Li = low | normal | high
344 When this option is used the priority of the tincd process will be adjusted.
345 Increasing the priority may help to reduce latency and packet loss on the VPN.
347 .It Va StrictSubnets Li = yes | no Po no Pc Bq experimental
348 When this option is enabled tinc will only use Subnet statements which are
349 present in the host config files in the local
350 .Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /hosts/
353 .It Va TunnelServer Li = yes | no Po no Pc Bq experimental
354 When this option is enabled tinc will no longer forward information between other tinc daemons,
355 and will only allow connections with nodes for which host config files are present in the local
356 .Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /hosts/
358 Setting this options also implicitly sets StrictSubnets.
361 .Sh HOST CONFIGURATION FILES
362 The host configuration files contain all information needed
363 to establish a connection to those hosts.
364 A host configuration file is also required for the local tinc daemon,
365 it will use it to read in it's listen port, public key and subnets.
368 The idea is that these files are portable.
369 You can safely mail your own host configuration file to someone else.
370 That other person can then copy it to his own hosts directory,
371 and now his tinc daemon will be able to connect to your tinc daemon.
372 Since host configuration files only contain public keys,
373 no secrets are revealed by sending out this information.
374 .Bl -tag -width indent
376 .It Va Address Li = Ar address Oo port Oc Bq recommended
377 The IP address or hostname of this tinc daemon on the real network.
378 This will only be used when trying to make an outgoing connection to this tinc daemon.
379 Optionally, a port can be specified to use for this address.
382 variables can be specified, in which case each address will be tried until a working
383 connection has been established.
385 .It Va Cipher Li = Ar cipher Pq blowfish
386 The symmetric cipher algorithm used to encrypt UDP packets.
387 Any cipher supported by OpenSSL is recognised.
388 Furthermore, specifying
390 will turn off packet encryption.
391 It is best to use only those ciphers which support CBC mode.
393 .It Va ClampMSS Li = yes | no Pq yes
394 This option specifies whether tinc should clamp the maximum segment size (MSS)
395 of TCP packets to the path MTU. This helps in situations where ICMP
396 Fragmentation Needed or Packet too Big messages are dropped by firewalls.
398 .It Va Compression Li = Ar level Pq 0
399 This option sets the level of compression used for UDP packets.
400 Possible values are 0 (off), 1 (fast zlib) and any integer up to 9 (best zlib),
401 10 (fast lzo) and 11 (best lzo).
403 .It Va Digest Li = Ar digest Pq sha1
404 The digest algorithm used to authenticate UDP packets.
405 Any digest supported by OpenSSL is recognised.
406 Furthermore, specifying
408 will turn off packet authentication.
410 .It Va IndirectData Li = yes | no Pq no
411 This option specifies whether other tinc daemons besides the one you specified with
413 can make a direct connection to you.
414 This is especially useful if you are behind a firewall
415 and it is impossible to make a connection from the outside to your tinc daemon.
416 Otherwise, it is best to leave this option out or set it to no.
418 .It Va MACLength Li = Ar length Pq 4
419 The length of the message authentication code used to authenticate UDP packets.
422 up to the length of the digest produced by the digest algorithm.
424 .It Va PMTU Li = Ar mtu Po 1514 Pc
425 This option controls the initial path MTU to this node.
427 .It Va PMTUDiscovery Li = yes | no Po yes Pc
428 When this option is enabled, tinc will try to discover the path MTU to this node.
429 After the path MTU has been discovered, it will be enforced on the VPN.
431 .It Va Port Li = Ar port Pq 655
432 The port number on which this tinc daemon is listening for incoming connections,
433 which is used if no port number is specified in an
437 .It Va PublicKey Li = Ar key Bq obsolete
438 The public RSA key of this tinc daemon.
439 It will be used to cryptographically verify it's identity and to set up a secure connection.
441 .It Va PublicKeyFile Li = Ar filename Bq obsolete
442 The file in which the public RSA key of this tinc daemon resides.
445 From version 1.0pre4 on
447 will store the public key directly into the host configuration file in PEM format,
448 the above two options then are not necessary.
449 Either the PEM format is used, or exactly one of the above two options must be specified
450 in each host configuration file,
451 if you want to be able to establish a connection with that host.
453 .It Va Subnet Li = Ar address Ns Op Li / Ns Ar prefixlength Ns Op Li # Ns Ar weight
454 The subnet which this tinc daemon will serve.
456 tries to look up which other daemon it should send a packet to by searching the appropriate subnet.
457 If the packet matches a subnet,
458 it will be sent to the daemon who has this subnet in his host configuration file.
461 variables can be specified.
464 Subnets can either be single MAC, IPv4 or IPv6 addresses,
465 in which case a subnet consisting of only that single address is assumed,
466 or they can be a IPv4 or IPv6 network address with a prefixlength.
467 Shorthand notations are not supported.
468 For example, IPv4 subnets must be in a form like 192.168.1.0/24,
469 where 192.168.1.0 is the network address and 24 is the number of bits set in the netmask.
470 Note that subnets like 192.168.1.1/24 are invalid!
471 Read a networking HOWTO/FAQ/guide if you don't understand this.
472 IPv6 subnets are notated like fec0:0:0:1:0:0:0:0/64.
473 MAC addresses are notated like 0:1a:2b:3c:4d:5e.
476 A Subnet can be given a weight to indicate its priority over identical Subnets
477 owned by different nodes. The default weight is 10. Lower values indicate
478 higher priority. Packets will be sent to the node with the highest priority,
479 unless that node is not reachable, in which case the node with the next highest
480 priority will be tried, and so on.
482 .It Va TCPOnly Li = yes | no Pq no Bq obsolete
483 If this variable is set to yes,
484 then the packets are tunnelled over the TCP connection instead of a UDP connection.
485 This is especially useful for those who want to run a tinc daemon
486 from behind a masquerading firewall,
487 or if UDP packet routing is disabled somehow.
488 Setting this options also implicitly sets IndirectData.
491 Since version 1.0.10, tinc will automatically detect whether communication via
492 UDP is possible or not.
496 Apart from reading the server and host configuration files,
497 tinc can also run scripts at certain moments.
498 Under Windows (not Cygwin), the scripts should have the extension
500 .Bl -tag -width indent
502 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /tinc-up
503 This is the most important script.
504 If it is present it will be executed right after the tinc daemon has been started and has connected to the virtual network device.
505 It should be used to set up the corresponding network interface,
506 but can also be used to start other things.
507 Under Windows you can use the Network Connections control panel instead of creating this script.
509 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /tinc-down
510 This script is started right before the tinc daemon quits.
512 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /hosts/ Ns Ar HOST Ns Pa -up
513 This script is started when the tinc daemon with name
517 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /hosts/ Ns Ar HOST Ns Pa -down
518 This script is started when the tinc daemon with name
522 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /host-up
523 This script is started when any host becomes reachable.
525 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /host-down
526 This script is started when any host becomes unreachable.
528 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /subnet-up
529 This script is started when a Subnet becomes reachable.
530 The Subnet and the node it belongs to are passed in environment variables.
532 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /subnet-down
533 This script is started when a Subnet becomes unreachable.
537 The scripts are started without command line arguments, but can make use of certain environment variables.
538 Under UNIX like operating systems the names of environment variables must be preceded by a
543 files, they have to be put between
546 .Bl -tag -width indent
549 If a netname was specified, this environment variable contains it.
552 Contains the name of this tinc daemon.
555 Contains the name of the virtual network device that tinc uses.
558 Contains the name of the virtual network interface that tinc uses.
559 This should be used for commands like
563 When a host becomes (un)reachable, this is set to its name.
564 If a subnet becomes (un)reachable, this is set to the owner of that subnet.
567 When a host becomes (un)reachable, this is set to its real address.
570 When a host becomes (un)reachable, this is set to the port number it uses for communication with other tinc daemons.
573 When a subnet becomes (un)reachable, this is set to the subnet.
576 When a subnet becomes (un)reachable, this is set to the subnet weight.
580 The most important files are:
581 .Bl -tag -width indent
583 .It Pa @sysconfdir@/tinc/
584 The top directory for configuration files.
586 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /tinc.conf
587 The default name of the server configuration file for net
590 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /hosts/
591 Host configuration files are kept in this directory.
593 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /tinc-up
594 If an executable file with this name exists,
595 it will be executed right after the tinc daemon has connected to the virtual network device.
596 It can be used to set up the corresponding network interface.
598 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /tinc-down
599 If an executable file with this name exists,
600 it will be executed right before the tinc daemon is going to close
601 its connection to the virtual network device.
606 .Pa http://www.tinc-vpn.org/ ,
607 .Pa http://www.linuxdoc.org/LDP/nag2/ .
610 The full documentation for
612 is maintained as a Texinfo manual.
613 If the info and tinc programs are properly installed at your site, the command
615 should give you access to the complete manual.
619 comes with ABSOLUTELY NO WARRANTY.
620 This is free software, and you are welcome to redistribute it under certain conditions;
621 see the file COPYING for details.