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 Here are all valid variables, listed in alphabetical order.
115 The default value is given between parentheses.
116 .Bl -tag -width indent
118 .It Va AddressFamily Li = ipv4 | ipv6 | any Pq any
119 This option affects the address family of listening and outgoing sockets.
122 is selected, then depending on the operating system both IPv4 and IPv6 or just
123 IPv6 listening sockets will be created.
125 .It Va BindToAddress Li = Ar address Bq experimental
126 If your computer has more than one IPv4 or IPv6 address,
128 will by default listen on all of them for incoming connections.
129 It is possible to bind only to a single address with this variable.
132 This option may not work on all platforms.
134 .It Va BindToInterface Li = Ar interface Bq experimental
135 If your computer has more than one network interface,
137 will by default listen on all of them for incoming connections.
138 It is possible to bind only to a single interface with this variable.
141 This option may not work on all platforms.
143 .It Va ConnectTo Li = Ar name
144 Specifies which other tinc daemon to connect to on startup.
147 variables may be specified,
148 in which case outgoing connections to each specified tinc daemon are made.
149 The names should be known to this tinc daemon
150 (i.e., there should be a host configuration file for the name on the
155 If you don't specify a host with
158 won't try to connect to other daemons at all,
159 and will instead just listen for incoming connections.
161 .It Va Device Li = Ar device Po Pa /dev/tap0 , Pa /dev/net/tun No or other depending on platform Pc
162 The virtual network device to use.
164 will automatically detect what kind of device it is.
165 Note that you can only use one device per daemon.
170 The info pages of the tinc package contain more information
171 about configuring the virtual network device.
173 .It Va DeviceType Li = tun | tunnohead | tunifhead | tap Po only supported on BSD platforms Pc
174 The type of the virtual network device.
175 Tinc will normally automatically select the right type, and this option should not be used.
176 However, in case tinc does not seem to correctly interpret packets received from the virtual network device,
177 using this option might help.
178 .Bl -tag -width indent
182 Depending on the platform, this can either be with or without an address family header (see below).
185 Set type to tun without an address family header.
186 Tinc will expect packets read from the virtual network device to start with an IP header.
187 On some platforms IPv6 packets cannot be read from or written to the device in this mode.
190 Set type to tun with an address family header.
191 Tinc will expect packets read from the virtual network device
192 to start with a four byte header containing the address family,
193 followed by an IP header.
194 This mode should support both IPv4 and IPv6 packets.
198 Tinc will expect packets read from the virtual network device
199 to start with an Ethernet header.
202 .It Va Forwarding Li = off | internal | kernel Pq internal
203 This option selects the way indirect packets are forwarded.
204 .Bl -tag -width indent
207 Incoming packets that are not meant for the local node,
208 but which should be forwarded to another node, are dropped.
211 Incoming packets that are meant for another node are forwarded by tinc internally.
214 This is the default mode, and unless you really know you need another forwarding mode, don't change it.
217 Incoming packets are always sent to the TUN/TAP device, even if the packets are not for the local node.
218 This is less efficient, but allows the kernel to apply its routing and firewall rules on them,
219 and can also help debugging.
222 .It Va GraphDumpFile Li = Ar filename Bq experimental
223 If this option is present,
225 will dump the current network graph to the file
227 every minute, unless there were no changes to the graph.
228 The file is in a format that can be read by graphviz tools.
231 starts with a pipe symbol |,
232 then the rest of the filename is interpreted as a shell command
233 that is executed, the graph is then sent to stdin.
235 .It Va Hostnames Li = yes | no Pq no
236 This option selects whether IP addresses (both real and on the VPN) should
237 be resolved. Since DNS lookups are blocking, it might affect tinc's
238 efficiency, even stopping the daemon for a few seconds every time it does
239 a lookup if your DNS server is not responding.
242 This does not affect resolving hostnames to IP addresses from the
243 host configuration files.
245 .It Va Interface Li = Ar interface
246 Defines the name of the interface corresponding to the virtual network device.
247 Depending on the operating system and the type of device this may or may not actually set the name of the interface.
248 Under Windows, this variable is used to select which network interface will be used.
251 this variable is almost always already correctly set.
253 .It Va KeyExpire Li = Ar seconds Pq 3600
254 This option controls the period the encryption keys used to encrypt the data are valid.
255 It is common practice to change keys at regular intervals to make it even harder for crackers,
256 even though it is thought to be nearly impossible to crack a single key.
258 .It Va MACExpire Li = Ar seconds Pq 600
259 This option controls the amount of time MAC addresses are kept before they are removed.
260 This only has effect when
265 .It Va MaxTimeout Li = Ar seconds Pq 900
266 This is the maximum delay before trying to reconnect to other tinc daemons.
268 .It Va Mode Li = router | switch | hub Pq router
269 This option selects the way packets are routed to other daemons.
270 .Bl -tag -width indent
275 variables in the host configuration files will be used to form a routing table.
276 Only unicast packets of routable protocols (IPv4 and IPv6) are supported in this mode.
279 This is the default mode, and unless you really know you need another mode, don't change it.
282 In this mode the MAC addresses of the packets on the VPN will be used to
283 dynamically create a routing table just like an Ethernet switch does.
284 Unicast, multicast and broadcast packets of every protocol that runs over Ethernet are supported in this mode
285 at the cost of frequent broadcast ARP requests and routing table updates.
288 This mode is primarily useful if you want to bridge Ethernet segments.
291 This mode is almost the same as the switch mode, but instead
292 every packet will be broadcast to the other daemons
293 while no routing table is managed.
296 .It Va Name Li = Ar name Bq required
297 This is the name which identifies this tinc daemon.
298 It must be unique for the virtual private network this daemon will connect to.
300 .It Va PingInterval Li = Ar seconds Pq 60
301 The number of seconds of inactivity that
303 will wait before sending a probe to the other end.
305 .It Va PingTimeout Li = Ar seconds Pq 5
306 The number of seconds to wait for a response to pings or to allow meta
307 connections to block. If the other end doesn't respond within this time,
308 the connection is terminated,
309 and the others will be notified of this.
311 .It Va PriorityInheritance Li = yes | no Po no Pc Bq experimental
312 When this option is enabled the value of the TOS field of tunneled IPv4 packets
313 will be inherited by the UDP packets that are sent out.
315 .It Va PrivateKey Li = Ar key Bq obsolete
316 The private RSA key of this tinc daemon.
317 It will allow this tinc daemon to authenticate itself to other daemons.
319 .It Va PrivateKeyFile Li = Ar filename Po Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /rsa_key.priv Pc
320 The file in which the private RSA key of this tinc daemon resides.
321 Note that there must be exactly one of
325 specified in the configuration file.
327 .It Va ProcessPriority Li = low | normal | high
328 When this option is used the priority of the tincd process will be adjusted.
329 Increasing the priority may help to reduce latency and packet loss on the VPN.
331 .It Va StrictSubnets Li = yes | no Po no Pc Bq experimental
332 When this option is enabled tinc will only use Subnet statements which are
333 present in the host config files in the local
334 .Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /hosts/
337 .It Va TunnelServer Li = yes | no Po no Pc Bq experimental
338 When this option is enabled tinc will no longer forward information between other tinc daemons,
339 and will only allow connections with nodes for which host config files are present in the local
340 .Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /hosts/
342 Setting this options also implicitly sets StrictSubnets.
345 .Sh HOST CONFIGURATION FILES
346 The host configuration files contain all information needed
347 to establish a connection to those hosts.
348 A host configuration file is also required for the local tinc daemon,
349 it will use it to read in it's listen port, public key and subnets.
352 The idea is that these files are portable.
353 You can safely mail your own host configuration file to someone else.
354 That other person can then copy it to his own hosts directory,
355 and now his tinc daemon will be able to connect to your tinc daemon.
356 Since host configuration files only contain public keys,
357 no secrets are revealed by sending out this information.
358 .Bl -tag -width indent
360 .It Va Address Li = Ar address Oo port Oc Bq recommended
361 The IP address or hostname of this tinc daemon on the real network.
362 This will only be used when trying to make an outgoing connection to this tinc daemon.
363 Optionally, a port can be specified to use for this address.
366 variables can be specified, in which case each address will be tried until a working
367 connection has been established.
369 .It Va Cipher Li = Ar cipher Pq blowfish
370 The symmetric cipher algorithm used to encrypt UDP packets.
371 Any cipher supported by OpenSSL is recognised.
372 Furthermore, specifying
374 will turn off packet encryption.
375 It is best to use only those ciphers which support CBC mode.
377 .It Va ClampMSS Li = yes | no Pq yes
378 This option specifies whether tinc should clamp the maximum segment size (MSS)
379 of TCP packets to the path MTU. This helps in situations where ICMP
380 Fragmentation Needed or Packet too Big messages are dropped by firewalls.
382 .It Va Compression Li = Ar level Pq 0
383 This option sets the level of compression used for UDP packets.
384 Possible values are 0 (off), 1 (fast zlib) and any integer up to 9 (best zlib),
385 10 (fast lzo) and 11 (best lzo).
387 .It Va Digest Li = Ar digest Pq sha1
388 The digest algorithm used to authenticate UDP packets.
389 Any digest supported by OpenSSL is recognised.
390 Furthermore, specifying
392 will turn off packet authentication.
394 .It Va IndirectData Li = yes | no Pq no
395 This option specifies whether other tinc daemons besides the one you specified with
397 can make a direct connection to you.
398 This is especially useful if you are behind a firewall
399 and it is impossible to make a connection from the outside to your tinc daemon.
400 Otherwise, it is best to leave this option out or set it to no.
402 .It Va MACLength Li = Ar length Pq 4
403 The length of the message authentication code used to authenticate UDP packets.
406 up to the length of the digest produced by the digest algorithm.
408 .It Va PMTU Li = Ar mtu Po 1514 Pc
409 This option controls the initial path MTU to this node.
411 .It Va PMTUDiscovery Li = yes | no Po yes Pc
412 When this option is enabled, tinc will try to discover the path MTU to this node.
413 After the path MTU has been discovered, it will be enforced on the VPN.
415 .It Va Port Li = Ar port Pq 655
416 The port number on which this tinc daemon is listening for incoming connections,
417 which is used if no port number is specified in an
421 .It Va PublicKey Li = Ar key Bq obsolete
422 The public RSA key of this tinc daemon.
423 It will be used to cryptographically verify it's identity and to set up a secure connection.
425 .It Va PublicKeyFile Li = Ar filename Bq obsolete
426 The file in which the public RSA key of this tinc daemon resides.
429 From version 1.0pre4 on
431 will store the public key directly into the host configuration file in PEM format,
432 the above two options then are not necessary.
433 Either the PEM format is used, or exactly one of the above two options must be specified
434 in each host configuration file,
435 if you want to be able to establish a connection with that host.
437 .It Va Subnet Li = Ar address Ns Op Li / Ns Ar prefixlength Ns Op Li # Ns Ar weight
438 The subnet which this tinc daemon will serve.
440 tries to look up which other daemon it should send a packet to by searching the appropriate subnet.
441 If the packet matches a subnet,
442 it will be sent to the daemon who has this subnet in his host configuration file.
445 variables can be specified.
448 Subnets can either be single MAC, IPv4 or IPv6 addresses,
449 in which case a subnet consisting of only that single address is assumed,
450 or they can be a IPv4 or IPv6 network address with a prefixlength.
451 Shorthand notations are not supported.
452 For example, IPv4 subnets must be in a form like 192.168.1.0/24,
453 where 192.168.1.0 is the network address and 24 is the number of bits set in the netmask.
454 Note that subnets like 192.168.1.1/24 are invalid!
455 Read a networking HOWTO/FAQ/guide if you don't understand this.
456 IPv6 subnets are notated like fec0:0:0:1:0:0:0:0/64.
457 MAC addresses are notated like 0:1a:2b:3c:4d:5e.
460 A Subnet can be given a weight to indicate its priority over identical Subnets
461 owned by different nodes. The default weight is 10. Lower values indicate
462 higher priority. Packets will be sent to the node with the highest priority,
463 unless that node is not reachable, in which case the node with the next highest
464 priority will be tried, and so on.
466 .It Va TCPOnly Li = yes | no Pq no Bq obsolete
467 If this variable is set to yes,
468 then the packets are tunnelled over the TCP connection instead of a UDP connection.
469 This is especially useful for those who want to run a tinc daemon
470 from behind a masquerading firewall,
471 or if UDP packet routing is disabled somehow.
472 Setting this options also implicitly sets IndirectData.
475 Since version 1.0.10, tinc will automatically detect whether communication via
476 UDP is possible or not.
480 Apart from reading the server and host configuration files,
481 tinc can also run scripts at certain moments.
482 Under Windows (not Cygwin), the scripts should have the extension
484 .Bl -tag -width indent
486 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /tinc-up
487 This is the most important script.
488 If it is present it will be executed right after the tinc daemon has been started and has connected to the virtual network device.
489 It should be used to set up the corresponding network interface,
490 but can also be used to start other things.
491 Under Windows you can use the Network Connections control panel instead of creating this script.
493 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /tinc-down
494 This script is started right before the tinc daemon quits.
496 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /hosts/ Ns Ar HOST Ns Pa -up
497 This script is started when the tinc daemon with name
501 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /hosts/ Ns Ar HOST Ns Pa -down
502 This script is started when the tinc daemon with name
506 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /host-up
507 This script is started when any host becomes reachable.
509 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /host-down
510 This script is started when any host becomes unreachable.
512 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /subnet-up
513 This script is started when a Subnet becomes reachable.
514 The Subnet and the node it belongs to are passed in environment variables.
516 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /subnet-down
517 This script is started when a Subnet becomes unreachable.
521 The scripts are started without command line arguments, but can make use of certain environment variables.
522 Under UNIX like operating systems the names of environment variables must be preceded by a
527 files, they have to be put between
530 .Bl -tag -width indent
533 If a netname was specified, this environment variable contains it.
536 Contains the name of this tinc daemon.
539 Contains the name of the virtual network device that tinc uses.
542 Contains the name of the virtual network interface that tinc uses.
543 This should be used for commands like
547 When a host becomes (un)reachable, this is set to its name.
548 If a subnet becomes (un)reachable, this is set to the owner of that subnet.
551 When a host becomes (un)reachable, this is set to its real address.
554 When a host becomes (un)reachable, this is set to the port number it uses for communication with other tinc daemons.
557 When a subnet becomes (un)reachable, this is set to the subnet.
560 When a subnet becomes (un)reachable, this is set to the subnet weight.
564 The most important files are:
565 .Bl -tag -width indent
567 .It Pa @sysconfdir@/tinc/
568 The top directory for configuration files.
570 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /tinc.conf
571 The default name of the server configuration file for net
574 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /hosts/
575 Host configuration files are kept in this directory.
577 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /tinc-up
578 If an executable file with this name exists,
579 it will be executed right after the tinc daemon has connected to the virtual network device.
580 It can be used to set up the corresponding network interface.
582 .It Pa @sysconfdir@/tinc/ Ns Ar NETNAME Ns Pa /tinc-down
583 If an executable file with this name exists,
584 it will be executed right before the tinc daemon is going to close
585 its connection to the virtual network device.
590 .Pa http://www.tinc-vpn.org/ ,
591 .Pa http://www.linuxdoc.org/LDP/nag2/ .
594 The full documentation for
596 is maintained as a Texinfo manual.
597 If the info and tinc programs are properly installed at your site, the command
599 should give you access to the complete manual.
603 comes with ABSOLUTELY NO WARRANTY.
604 This is free software, and you are welcome to redistribute it under certain conditions;
605 see the file COPYING for details.