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Revision: 1.25
Committed: Sat Jul 18 05:59:16 2009 UTC (14 years, 10 months ago) by pcg
Branch: MAIN
Changes since 1.24: +15 -7 lines
Log Message:
riddify us of meta.yml garbage in manifest

File Contents

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132 .\" ========================================================================
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134 .IX Title "GVPE.CONF 5"
135 .TH GVPE.CONF 5 "2009-06-01" "2.22" "GNU Virtual Private Ethernet"
136 .\" For nroff, turn off justification. Always turn off hyphenation; it makes
137 .\" way too many mistakes in technical documents.
138 .if n .ad l
139 .nh
140 .SH "NAME"
141 gvpe.conf \- configuration file for the GNU VPE daemon
142 .SH "SYNOPSIS"
143 .IX Header "SYNOPSIS"
144 .Vb 4
145 \& # global options for all nodes
146 \& udp\-port = 407
147 \& mtu = 1492
148 \& ifname = vpn0
149 \&
150 \& # first node is named branch1 and is at 1.2.3.4
151 \& node = branch1
152 \& hostname = 1.2.3.4
153 \&
154 \& # second node uses dns to resolve the address
155 \& node = branch2
156 \& hostname = www.example.net
157 \& udp\-port = 500 # this host uses a different udp\-port
158 \&
159 \& # third node has no fixed ip address
160 \& node = branch3
161 \& connect = ondemand
162 .Ve
163 .SH "DESCRIPTION"
164 .IX Header "DESCRIPTION"
165 The gvpe config file consists of a series of lines that contain \f(CW\*(C`variable
166 = value\*(C'\fR pairs. Empty lines are ignored. Comments start with a \f(CW\*(C`#\*(C'\fR and
167 extend to the end of the line. They can be used on their own lines, or
168 after any directives. Whitespace is allowed around the \f(CW\*(C`=\*(C'\fR sign or after
169 values, but not within the variable names or values themselves.
170 .PP
171 The only exception to the above is the \*(L"on\*(R" directive that can prefix any
172 \&\f(CW\*(C`name = value\*(C'\fR setting and will only \*(L"execute\*(R" it on the named node, or
173 (if the nodename starts with \*(L"!\*(R") on all nodes except the named one.
174 .PP
175 For example, set the \s-1MTU\s0 to \f(CW1450\fR everywhere, loglevel to \f(CW\*(C`noise\*(C'\fR on
176 branch1, and connect to \f(CW\*(C`ondemand\*(C'\fR everywhere but on branch2:
177 .PP
178 .Vb 3
179 \& mtu = 1450
180 \& on branch1 loglevel = noise
181 \& on !branch2 connect = ondemand
182 .Ve
183 .PP
184 All settings are applied \*(L"in order\*(R", that is, later settings of the same
185 variable overwrite earlier ones.
186 .SH "ANATOMY OF A CONFIG FILE"
187 .IX Header "ANATOMY OF A CONFIG FILE"
188 Usually, a config file starts with a few global settings (like the \s-1UDP\s0
189 port to listen on), followed by node-specific sections that begin with a
190 \&\f(CW\*(C`node = nickname\*(C'\fR line.
191 .PP
192 Every node that is part of the network must have a section that starts
193 with \f(CW\*(C`node = nickname\*(C'\fR. The number and order of the nodes is important
194 and must be the same on all nodes. It is not uncommon for node sections to
195 be completely empty \- if the default values are right.
196 .PP
197 Node-specific settings can be used at any time. If used before the first
198 node section they will set the default values for all following nodes.
199 .SH "CONFIG VARIABLES"
200 .IX Header "CONFIG VARIABLES"
201 .Sh "\s-1GLOBAL\s0 \s-1SETTINGS\s0"
202 .IX Subsection "GLOBAL SETTINGS"
203 Global settings will affect the behaviour of the running gvpe daemon, that
204 is, they are in some sense node-specific (config files can set different
205 values on different nodes using \f(CW\*(C`on\*(C'\fR), but will affect the behaviour of
206 the gvpe daemon and all connections it creates.
207 .IP "dns-forw-host = hostname/ip" 4
208 .IX Item "dns-forw-host = hostname/ip"
209 The \s-1DNS\s0 server to forward \s-1DNS\s0 requests to for the \s-1DNS\s0 tunnel protocol
210 (default: \f(CW127.0.0.1\fR, changing it is highly recommended).
211 .IP "dns-forw-port = port-number" 4
212 .IX Item "dns-forw-port = port-number"
213 The port where the \f(CW\*(C`dns\-forw\-host\*(C'\fR is to be contacted (default: \f(CW53\fR,
214 which is fine in most cases).
215 .IP "dns-max-outstanding = integer-number-of-requests" 4
216 .IX Item "dns-max-outstanding = integer-number-of-requests"
217 The maximum number of outstanding \s-1DNS\s0 transport requests
218 (default: \f(CW100\fR). \s-1GVPE\s0 will never issue more requests then the given
219 limit without receiving replies. In heavily overloaded situations it might
220 help to set this to a low number (e.g. \f(CW3\fR or even \f(CW1\fR) to limit the
221 number of parallel requests.
222 .Sp
223 The default should be working \s-1OK\s0 for most links.
224 .IP "dns-overlap-factor = float" 4
225 .IX Item "dns-overlap-factor = float"
226 The \s-1DNS\s0 transport uses the minimum request latency (\fBmin_latency\fR) seen
227 during a connection as it's timing base. This factor (default: \f(CW0.5\fR,
228 must be > 0) is multiplied by \fBmin_latency\fR to get the maximum sending
229 rate (= minimum send interval), i.e. a factor of \f(CW1\fR means that a new
230 request might be generated every \fBmin_latency\fR seconds, which means on
231 average there should only ever be one outstanding request. A factor of
232 \&\f(CW0.5\fR means that \s-1GVPE\s0 will send requests twice as often as the minimum
233 latency measured.
234 .Sp
235 For congested or picky \s-1DNS\s0 forwarders you could use a value nearer to or
236 exceeding \f(CW1\fR.
237 .Sp
238 The default should be working \s-1OK\s0 for most links.
239 .IP "dns-send-interval = send-interval-in-seconds" 4
240 .IX Item "dns-send-interval = send-interval-in-seconds"
241 The minimum send interval (= maximum rate) that the \s-1DNS\s0 transport will
242 use to send new \s-1DNS\s0 requests. \s-1GVPE\s0 will not exceed this rate even when
243 the latency is very low. The default is \f(CW0.01\fR, which means \s-1GVPE\s0 will
244 not send more than 100 \s-1DNS\s0 requests per connection per second. For
245 high-bandwidth links you could go lower, e.g. to \f(CW0.001\fR or so. For
246 congested or rate-limited links, you might want to go higher, say \f(CW0.1\fR,
247 \&\f(CW0.2\fR or even higher.
248 .Sp
249 The default should be working \s-1OK\s0 for most links.
250 .IP "dns-timeout-factor = float" 4
251 .IX Item "dns-timeout-factor = float"
252 Factor to multiply the \f(CW\*(C`min_latency\*(C'\fR (see \f(CW\*(C`dns\-overlap\-factor\*(C'\fR) by to
253 get request timeouts. The default of \f(CW8\fR means that the \s-1DNS\s0 transport
254 will resend the request when no reply has been received for longer than
255 eight times the minimum (= expected) latency, assuming the request or
256 reply has been lost.
257 .Sp
258 For congested links a higher value might be necessary (e.g. \f(CW30\fR). If
259 the link is very stable lower values (e.g. \f(CW2\fR) might work
260 nicely. Values near or below \f(CW1\fR makes no sense whatsoever.
261 .Sp
262 The default should be working \s-1OK\s0 for most links but will result in low
263 throughput if packet loss is high.
264 .IP "if-up = relative-or-absolute-path" 4
265 .IX Item "if-up = relative-or-absolute-path"
266 Sets the path of a script that should be called immediately after the
267 network interface is initialized (but not necessarily up). The following
268 environment variables are passed to it (the values are just examples).
269 .Sp
270 Variables that have the same value on all nodes:
271 .RS 4
272 .IP "CONFBASE=/etc/gvpe" 4
273 .IX Item "CONFBASE=/etc/gvpe"
274 The configuration base directory.
275 .IP "IFNAME=vpn0" 4
276 .IX Item "IFNAME=vpn0"
277 The network interface to initialize.
278 .IP "IFTYPE=native # or tincd" 4
279 .IX Item "IFTYPE=native # or tincd"
280 .PD 0
281 .IP "IFSUBTYPE=linux # or freebsd, darwin etc.." 4
282 .IX Item "IFSUBTYPE=linux # or freebsd, darwin etc.."
283 .PD
284 The interface type (\f(CW\*(C`native\*(C'\fR or \f(CW\*(C`tincd\*(C'\fR) and the subtype (usually the
285 \&\s-1OS\s0 name in lowercase) that this \s-1GVPE\s0 was configured for. Can be used to
286 select the correct syntax to use for network-related commands.
287 .IP "MTU=1436" 4
288 .IX Item "MTU=1436"
289 The \s-1MTU\s0 to set the interface to. You can use lower values (if done
290 consistently on all nodes), but this is usually either inefficient or
291 simply ineffective.
292 .IP "NODES=5" 4
293 .IX Item "NODES=5"
294 The number of nodes in this \s-1GVPE\s0 network.
295 .RE
296 .RS 4
297 .Sp
298 Variables that are node-specific and with values pertaining to the node
299 running this \s-1GVPE:\s0
300 .IP "IFUPDATA=string" 4
301 .IX Item "IFUPDATA=string"
302 The value of the configuration directive \f(CW\*(C`if\-up\-data\*(C'\fR.
303 .IP "MAC=fe:fd:80:00:00:01" 4
304 .IX Item "MAC=fe:fd:80:00:00:01"
305 The \s-1MAC\s0 address the network interface has to use.
306 .Sp
307 Might be used to initialize interfaces on platforms where \s-1GVPE\s0 does not
308 do this automatically. Please see the \f(CW\*(C`gvpe.osdep(5)\*(C'\fR man page for
309 platform-specific information.
310 .IP "NODENAME=branch1" 4
311 .IX Item "NODENAME=branch1"
312 The nickname of the node.
313 .IP "NODEID=1" 4
314 .IX Item "NODEID=1"
315 The numerical node \s-1ID\s0 of the node running this instance of \s-1GVPE\s0. The first
316 node mentioned in the config file gets \s-1ID\s0 1, the second \s-1ID\s0 2 and so on.
317 .RE
318 .RS 4
319 .Sp
320 In addition, all node-specific variables (except \f(CW\*(C`NODEID\*(C'\fR) will be
321 available with a postfix of \f(CW\*(C`_nodeid\*(C'\fR, which contains the value for that
322 node, e.g. the \f(CW\*(C`MAC_1\*(C'\fR variable contains the \s-1MAC\s0 address of node #1, while
323 the \f(CW\*(C`NODENAME_22\*(C'\fR variable contains the name of node #22.
324 .Sp
325 Here is a simple if-up script:
326 .Sp
327 .Vb 5
328 \& #!/bin/sh
329 \& ip link set $IFNAME up
330 \& [ $NODENAME = branch1 ] && ip addr add 10.0.0.1 dev $IFNAME
331 \& [ $NODENAME = branch2 ] && ip addr add 10.1.0.1 dev $IFNAME
332 \& ip route add 10.0.0.0/8 dev $IFNAME
333 .Ve
334 .Sp
335 More complicated examples (using routing to reduce \s-1ARP\s0 traffic) can be
336 found in the \fIetc/\fR subdirectory of the distribution.
337 .RE
338 .IP "ifname = devname" 4
339 .IX Item "ifname = devname"
340 Sets the tun interface name to the given name. The default is OS-specific
341 and most probably something like \f(CW\*(C`tun0\*(C'\fR.
342 .IP "ifpersist = yes|true|on | no|false|off" 4
343 .IX Item "ifpersist = yes|true|on | no|false|off"
344 Should the tun/tap device be made persistent, that is, should the device
345 stay up even when gvpe exits? Some versions of the tunnel device have
346 problems sending packets when gvpe is restarted in persistent mode, so
347 if the connections can be established but you cannot send packets from
348 the local node, try to set this to \f(CW\*(C`off\*(C'\fR and do an ifconfig down on the
349 device.
350 .IP "ip-proto = numerical-ip-protocol" 4
351 .IX Item "ip-proto = numerical-ip-protocol"
352 Sets the protocol number to be used for the rawip protocol. This is a
353 global option because all nodes must use the same protocol, and since
354 there are no port numbers, you cannot easily run more than one gvpe
355 instance using the same protocol, nor can you share the protocol with
356 other programs.
357 .Sp
358 The default is 47 (\s-1GRE\s0), which has a good chance of tunneling
359 through firewalls (but note that gvpe's rawip protocol is not \s-1GRE\s0
360 compatible). Other common choices are 50 (\s-1IPSEC\s0, \s-1ESP\s0), 51 (\s-1IPSEC\s0, \s-1AH\s0), 4
361 (\s-1IPIP\s0 tunnels) or 98 (\s-1ENCAP\s0, rfc1241)
362 .IP "http-proxy-host = hostname/ip" 4
363 .IX Item "http-proxy-host = hostname/ip"
364 The \f(CW\*(C`http\-proxy\-*\*(C'\fR family of options are only available if gvpe was
365 compiled with the \f(CW\*(C`\-\-enable\-http\-proxy\*(C'\fR option and enable tunneling of
366 tcp connections through a http proxy server.
367 .Sp
368 \&\f(CW\*(C`http\-proxy\-host\*(C'\fR and \f(CW\*(C`http\-proxy\-port\*(C'\fR should specify the hostname and
369 port number of the proxy server. See \f(CW\*(C`http\-proxy\-loginpw\*(C'\fR if your proxy
370 requires authentication.
371 .Sp
372 Please note that gvpe will still try to resolve all hostnames in the
373 configuration file, so if you are behind a proxy without access to a \s-1DNS\s0
374 server better use numerical \s-1IP\s0 addresses.
375 .Sp
376 To make best use of this option disable all protocols except \s-1TCP\s0 in your
377 config file and make sure your routers (or all other nodes) are listening
378 on a port that the proxy allows (443, https, is a common choice).
379 .Sp
380 If you have a router, connecting to it will suffice. Otherwise \s-1TCP\s0 must be
381 enabled on all nodes.
382 .Sp
383 Example:
384 .Sp
385 .Vb 3
386 \& http\-proxy\-host = proxy.example.com
387 \& http\-proxy\-port = 3128 # 8080 is another common choice
388 \& http\-proxy\-auth = schmorp:grumbeere
389 .Ve
390 .IP "http-proxy-port = proxy-tcp-port" 4
391 .IX Item "http-proxy-port = proxy-tcp-port"
392 The port where your proxy server listens.
393 .IP "http-proxy-auth = login:password" 4
394 .IX Item "http-proxy-auth = login:password"
395 The optional login and password used to authenticate to the proxy server,
396 separated by a literal colon (\f(CW\*(C`:\*(C'\fR). Only basic authentication is
397 currently supported.
398 .IP "keepalive = seconds" 4
399 .IX Item "keepalive = seconds"
400 Sets the keepalive probe interval in seconds (default: \f(CW60\fR). After this
401 many seconds of inactivity the daemon will start to send keepalive probe
402 every 3 seconds until it receives a reply from the other end. If no reply
403 is received within 15 seconds, the peer is considered unreachable and the
404 connection is closed.
405 .IP "loglevel = noise|trace|debug|info|notice|warn|error|critical" 4
406 .IX Item "loglevel = noise|trace|debug|info|notice|warn|error|critical"
407 Set the logging level. Connection established messages are logged at level
408 \&\f(CW\*(C`info\*(C'\fR, notable errors are logged with \f(CW\*(C`error\*(C'\fR. Default is \f(CW\*(C`info\*(C'\fR.
409 .IP "mtu = bytes" 4
410 .IX Item "mtu = bytes"
411 Sets the maximum \s-1MTU\s0 that should be used on outgoing packets (basically
412 the \s-1MTU\s0 of the outgoing interface) The daemon will automatically calculate
413 maximum overhead (e.g. \s-1UDP\s0 header size, encryption blocksize...) and pass
414 this information to the \f(CW\*(C`if\-up\*(C'\fR script.
415 .Sp
416 Recommended values are 1500 (ethernet), 1492 (pppoe), 1472 (pptp).
417 .Sp
418 This value must be the minimum of the \s-1MTU\s0 values of all nodes.
419 .IP "node = nickname" 4
420 .IX Item "node = nickname"
421 Not really a config setting but introduces a node section. The nickname is
422 used to select the right configuration section and must be passed as an
423 argument to the gvpe daemon.
424 .IP "node-up = relative-or-absolute-path" 4
425 .IX Item "node-up = relative-or-absolute-path"
426 Sets a command (default: none) that should be called whenever a connection
427 is established (even on rekeying operations). Note that node\-up/down
428 scripts will be run asynchronously, but execution is serialised, so there
429 will only ever be one such script running.
430 .Sp
431 In addition to all the variables passed to \f(CW\*(C`if\-up\*(C'\fR scripts, the following
432 environment variables will be set (values are just examples):
433 .RS 4
434 .IP "DESTNODE=branch2" 4
435 .IX Item "DESTNODE=branch2"
436 The name of the remote node.
437 .IP "DESTID=2" 4
438 .IX Item "DESTID=2"
439 The node id of the remote node.
440 .IP "DESTSI=rawip/88.99.77.55:0" 4
441 .IX Item "DESTSI=rawip/88.99.77.55:0"
442 The \*(L"socket info\*(R" of the target node, protocol dependent but usually in
443 the format protocol/ip:port.
444 .IP "DESTIP=188.13.66.8" 4
445 .IX Item "DESTIP=188.13.66.8"
446 The numerical \s-1IP\s0 address of the remote node (gvpe accepts connections from
447 everywhere, as long as the other node can authenticate itself).
448 .IP "DESTPORT=655 # deprecated" 4
449 .IX Item "DESTPORT=655 # deprecated"
450 The protocol port used by the other side, if applicable.
451 .IP "STATE=up" 4
452 .IX Item "STATE=up"
453 Node-up scripts get called with STATE=up, node-change scripts get called
454 with STATE=change and node-down scripts get called with STATE=down.
455 .RE
456 .RS 4
457 .Sp
458 Here is a nontrivial example that uses nsupdate to update the name => ip
459 mapping in some \s-1DNS\s0 zone:
460 .Sp
461 .Vb 6
462 \& #!/bin/sh
463 \& {
464 \& echo update delete $DESTNODE.lowttl.example.net. a
465 \& echo update add $DESTNODE.lowttl.example.net. 1 in a $DESTIP
466 \& echo
467 \& } | nsupdate \-d \-k $CONFBASE:key.example.net.
468 .Ve
469 .RE
470 .IP "node-change = relative-or-absolute-path" 4
471 .IX Item "node-change = relative-or-absolute-path"
472 Same as \f(CW\*(C`node\-change\*(C'\fR, but gets called whenever something about a
473 connection changes (such as the source \s-1IP\s0 address).
474 .IP "node-down = relative-or-absolute-path" 4
475 .IX Item "node-down = relative-or-absolute-path"
476 Same as \f(CW\*(C`node\-up\*(C'\fR, but gets called whenever a connection is lost.
477 .IP "pid-file = path" 4
478 .IX Item "pid-file = path"
479 The path to the pid file to check and create
480 (default: \f(CW\*(C`LOCALSTATEDIR/run/gvpe.pid\*(C'\fR).
481 .IP "private-key = relative-path-to-key" 4
482 .IX Item "private-key = relative-path-to-key"
483 Sets the path (relative to the config directory) to the private key
484 (default: \f(CW\*(C`hostkey\*(C'\fR). This is a printf format string so every \f(CW\*(C`%\*(C'\fR must
485 be doubled. A single \f(CW%s\fR is replaced by the hostname, so you could
486 use paths like \f(CW\*(C`hostkeys/%s\*(C'\fR to fetch the files at the location where
487 \&\f(CW\*(C`gvpectrl\*(C'\fR puts them.
488 .Sp
489 Since only the private key file of the current node is used and the
490 private key file should be kept secret per-node to avoid spoofing, it is
491 not recommended to use this feature.
492 .IP "rekey = seconds" 4
493 .IX Item "rekey = seconds"
494 Sets the rekeying interval in seconds (default: \f(CW3600\fR). Connections are
495 reestablished every \f(CW\*(C`rekey\*(C'\fR seconds, making them use a new encryption
496 key.
497 .IP "nfmark = integer" 4
498 .IX Item "nfmark = integer"
499 This advanced option, when set to a nonzero value (default: \f(CW0\fR), tries
500 to set the netfilter mark (or fwmark) value on all sockets gvpe uses to
501 send packets.
502 .Sp
503 This can be used to make gvpe use a different set of routing rules. For
504 example, on GNU/Linux, the \f(CW\*(C`if\-up\*(C'\fR could set \f(CW\*(C`nfmark\*(C'\fR to 1000 and then
505 put all routing rules into table \f(CW99\fR and then use an ip rule to make
506 gvpe traffic avoid that routing table, in effect routing normal traffic
507 via gvpe and gvpe traffic via the normal system routing tables:
508 .Sp
509 .Vb 1
510 \& ip rule add not fwmark 1000 lookup 99
511 .Ve
512 .Sh "\s-1NODE\s0 \s-1SPECIFIC\s0 \s-1SETTINGS\s0"
513 .IX Subsection "NODE SPECIFIC SETTINGS"
514 The following settings are node-specific, that is, every node can have
515 different settings, even within the same gvpe instance. Settings that are
516 set before the first node section set the defaults, settings that are
517 set within a node section only apply to the given node.
518 .IP "allow-direct = nodename" 4
519 .IX Item "allow-direct = nodename"
520 Allow direct connections to this node. See \f(CW\*(C`deny\-direct\*(C'\fR for more info.
521 .IP "compress = yes|true|on | no|false|off" 4
522 .IX Item "compress = yes|true|on | no|false|off"
523 Wether to compress data packets sent to this node (default: \f(CW\*(C`yes\*(C'\fR).
524 Compression is really cheap even on slow computers and has no size
525 overhead at all, so enabling this is often a good idea.
526 .IP "connect = ondemand | never | always | disabled" 4
527 .IX Item "connect = ondemand | never | always | disabled"
528 Sets the connect mode (default: \f(CW\*(C`always\*(C'\fR). It can be \f(CW\*(C`always\*(C'\fR (always
529 try to establish and keep a connection to the given node), \f(CW\*(C`never\*(C'\fR
530 (never initiate a connection to the given host, but accept connections),
531 \&\f(CW\*(C`ondemand\*(C'\fR (try to establish a connection when there are outstanding
532 packets in the queue and take it down after the keepalive interval) or
533 \&\f(CW\*(C`disabled\*(C'\fR (node is bad, don't talk to it).
534 .Sp
535 Routers will automatically be forced to \f(CW\*(C`always\*(C'\fR unless they are
536 \&\f(CW\*(C`disabled\*(C'\fR, to ensure all nodes can talk to each other.
537 .IP "deny-direct = nodename | *" 4
538 .IX Item "deny-direct = nodename | *"
539 Deny direct connections to the specified node (or all nodes when \f(CW\*(C`*\*(C'\fR
540 is given). Only one node can be specified, but you can use multiple
541 \&\f(CW\*(C`allow\-direct\*(C'\fR and \f(CW\*(C`deny\-direct\*(C'\fR statements. This only makes sense in
542 networks with routers, as routers are required for indirect connections.
543 .Sp
544 Sometimes, a node cannot reach some other nodes for reasons of network
545 connectivity. For example, a node behind a firewall that only allows
546 connections to/from a single other node in the network. In this case one
547 should specify \f(CW\*(C`deny\-direct = *\*(C'\fR and \f(CW\*(C`allow\-direct = othernodename\*(C'\fR (the other
548 node \fImust\fR be a router for this to work).
549 .Sp
550 The algorithm to check whether a connection may be direct is as follows:
551 .Sp
552 1. Other node mentioned in an \f(CW\*(C`allow\-direct\*(C'\fR? If yes, allow the connection.
553 .Sp
554 2. Other node mentioned in a \f(CW\*(C`deny\-direct\*(C'\fR? If yes, deny direct connections.
555 .Sp
556 3. Allow the connection.
557 .Sp
558 That is, \f(CW\*(C`allow\-direct\*(C'\fR takes precedence over \f(CW\*(C`deny\-direct\*(C'\fR.
559 .Sp
560 The check is done in both directions, i.e. both nodes must allow a direct
561 connection before one is attempted, so you only need to specify connect
562 limitations on one node.
563 .IP "dns-domain = domain-suffix" 4
564 .IX Item "dns-domain = domain-suffix"
565 The \s-1DNS\s0 domain suffix that points to the \s-1DNS\s0 tunnel server for this node.
566 .Sp
567 The domain must point to a \s-1NS\s0 record that points to the \fIdns-hostname\fR,
568 i.e.
569 .Sp
570 .Vb 2
571 \& dns\-domainname = tunnel.example.net
572 \& dns\-hostname = tunnel\-server.example.net
573 .Ve
574 .Sp
575 Corresponds to the following \s-1DNS\s0 entries in the \f(CW\*(C`example.net\*(C'\fR domain:
576 .Sp
577 .Vb 2
578 \& tunnel.example.net. NS tunnel\-server.example.net.
579 \& tunnel\-server.example.net. A 13.13.13.13
580 .Ve
581 .IP "dns-hostname = hostname/ip" 4
582 .IX Item "dns-hostname = hostname/ip"
583 The address to bind the \s-1DNS\s0 tunnel socket to, similar to the \f(CW\*(C`hostname\*(C'\fR,
584 but for the \s-1DNS\s0 tunnel protocol only. Default: \f(CW0.0.0.0\fR, but that might
585 change.
586 .IP "dns-port = port-number" 4
587 .IX Item "dns-port = port-number"
588 The port to bind the \s-1DNS\s0 tunnel socket to. Must be \f(CW53\fR on \s-1DNS\s0 tunnel servers.
589 .IP "enable-dns = yes|true|on | no|false|off" 4
590 .IX Item "enable-dns = yes|true|on | no|false|off"
591 See \fIgvpe.protocol\fR\|(7) for a description of the \s-1DNS\s0 transport
592 protocol. Avoid this protocol if you can.
593 .Sp
594 Enable the \s-1DNS\s0 tunneling protocol on this node, either as server or as
595 client. Support for this transport protocol is only available when gvpe
596 was compiled using the \f(CW\*(C`\-\-enable\-dns\*(C'\fR option.
597 .IP "enable-icmp = yes|true|on | no|false|off" 4
598 .IX Item "enable-icmp = yes|true|on | no|false|off"
599 See \fIgvpe.protocol\fR\|(7) for a description of the \s-1ICMP\s0 transport protocol.
600 .Sp
601 Enable the \s-1ICMP\s0 transport using \s-1ICMP\s0 packets of type \f(CW\*(C`icmp\-type\*(C'\fR on this
602 node.
603 .IP "enable-rawip = yes|true|on | no|false|off" 4
604 .IX Item "enable-rawip = yes|true|on | no|false|off"
605 See \fIgvpe.protocol\fR\|(7) for a description of the \s-1RAW\s0 \s-1IP\s0 transport protocol.
606 .Sp
607 Enable the \s-1RAW\s0 IPv4 transport using the \f(CW\*(C`ip\-proto\*(C'\fR protocol
608 (default: \f(CW\*(C`no\*(C'\fR).
609 .IP "enable-tcp = yes|true|on | no|false|off" 4
610 .IX Item "enable-tcp = yes|true|on | no|false|off"
611 See \fIgvpe.protocol\fR\|(7) for a description of the \s-1TCP\s0 transport protocol.
612 .Sp
613 Enable the TCPv4 transport using the \f(CW\*(C`tcp\-port\*(C'\fR port
614 (default: \f(CW\*(C`no\*(C'\fR). Support for this transport protocol is only available
615 when gvpe was compiled using the \f(CW\*(C`\-\-enable\-tcp\*(C'\fR option.
616 .IP "enable-udp = yes|true|on | no|false|off" 4
617 .IX Item "enable-udp = yes|true|on | no|false|off"
618 See \fIgvpe.protocol\fR\|(7) for a description of the \s-1UDP\s0 transport protocol.
619 .Sp
620 Enable the UDPv4 transport using the \f(CW\*(C`udp\-port\*(C'\fR port (default: \f(CW\*(C`no\*(C'\fR,
621 unless no other protocol is enabled for a node, in which case this
622 protocol is enabled automatically).
623 .Sp
624 \&\s-1NOTE:\s0 Please specify \f(CW\*(C`enable\-udp = yes\*(C'\fR if you want to use it even though
625 it might get switched on automatically, as some future version might
626 default to another default protocol.
627 .IP "hostname = hostname | ip [can not be defaulted]" 4
628 .IX Item "hostname = hostname | ip [can not be defaulted]"
629 Forces the address of this node to be set to the given \s-1DNS\s0 hostname or \s-1IP\s0
630 address. It will be resolved before each connect request, so dyndns should
631 work fine. If this setting is not specified and a router is available,
632 then the router will be queried for the address of this node. Otherwise,
633 the connection attempt will fail.
634 .Sp
635 Note that \s-1DNS\s0 resolving is done synchronously, pausing the daemon. If that
636 is an issue you need to specify \s-1IP\s0 addresses.
637 .IP "icmp-type = integer" 4
638 .IX Item "icmp-type = integer"
639 Sets the type value to be used for outgoing (and incoming) packets sent
640 via the \s-1ICMP\s0 transport.
641 .Sp
642 The default is \f(CW0\fR (which is \f(CW\*(C`echo\-reply\*(C'\fR, also known as
643 \&\*(L"ping-reply\*(R"). Other useful values include \f(CW8\fR (\f(CW\*(C`echo\-request\*(C'\fR, a.k.a.
644 \&\*(L"ping\*(R") and \f(CW11\fR (\f(CW\*(C`time\-exceeded\*(C'\fR), but any 8\-bit value can be used.
645 .IP "if-up-data = value" 4
646 .IX Item "if-up-data = value"
647 The value specified using this directive will be passed to the \f(CW\*(C`if\-up\*(C'\fR
648 script in the environment variable \f(CW\*(C`IFUPDATA\*(C'\fR.
649 .IP "inherit-tos = yes|true|on | no|false|off" 4
650 .IX Item "inherit-tos = yes|true|on | no|false|off"
651 Wether to inherit the \s-1TOS\s0 settings of packets sent to the tunnel when
652 sending packets to this node (default: \f(CW\*(C`yes\*(C'\fR). If set to \f(CW\*(C`yes\*(C'\fR then
653 outgoing tunnel packets will have the same \s-1TOS\s0 setting as the packets sent
654 to the tunnel device, which is usually what you want.
655 .IP "max-retry = positive-number" 4
656 .IX Item "max-retry = positive-number"
657 The maximum interval in seconds (default: \f(CW3600\fR, one hour) between
658 retries to establish a connection to this node. When a connection cannot
659 be established, gvpe uses exponential back-off capped at this value. It's
660 sometimes useful to set this to a much lower value (e.g. \f(CW120\fR) on
661 connections to routers that usually are stable but sometimes are down, to
662 assure quick reconnections even after longer downtimes.
663 .IP "max-ttl = seconds" 4
664 .IX Item "max-ttl = seconds"
665 Expire packets that couldn't be sent after this many seconds
666 (default: \f(CW60\fR). Gvpe will normally queue packets for a node without an
667 active connection, in the hope of establishing a connection soon. This
668 value specifies the maximum lifetime a packet will stay in the queue, if a
669 packet gets older, it will be thrown away.
670 .IP "max-queue = positive\-number>=1" 4
671 .IX Item "max-queue = positive-number>=1"
672 The maximum number of packets that will be queued (default: \f(CW512\fR)
673 for this node. If more packets are sent then earlier packets will be
674 expired. See \f(CW\*(C`max\-ttl\*(C'\fR, above.
675 .IP "router-priority = 0 | 1 | positive\-number>=2" 4
676 .IX Item "router-priority = 0 | 1 | positive-number>=2"
677 Sets the router priority of the given node (default: \f(CW0\fR, disabled).
678 .Sp
679 If some node tries to connect to another node but it doesn't have a
680 hostname, it asks a router node for it's \s-1IP\s0 address. The router node
681 chosen is the one with the highest priority larger than \f(CW1\fR that is
682 currently reachable. This is called a \fImediated\fR connection, as the
683 connection itself will still be direct, but it uses another node to
684 mediate between the two nodes.
685 .Sp
686 The value \f(CW0\fR disables routing, that means if the node receives a packet
687 not for itself it will not forward it but instead drop it.
688 .Sp
689 The special value \f(CW1\fR allows other hosts to route through the router
690 host, but they will never route through it by default (i.e. the config
691 file of another node needs to specify a router priority higher than one
692 to choose such a node for routing).
693 .Sp
694 The idea behind this is that some hosts can, if required, bump the
695 \&\f(CW\*(C`router\-priority\*(C'\fR setting to higher than \f(CW1\fR in their local config to
696 route through specific hosts. If \f(CW\*(C`router\-priority\*(C'\fR is \f(CW0\fR, then routing
697 will be refused, so \f(CW1\fR serves as a \*(L"enable, but do not use by default\*(R"
698 switch.
699 .Sp
700 Nodes with \f(CW\*(C`router\-priority\*(C'\fR set to \f(CW2\fR or higher will always be forced
701 to \f(CW\*(C`connect\*(C'\fR = \f(CW\*(C`always\*(C'\fR (unless they are \f(CW\*(C`disabled\*(C'\fR).
702 .IP "tcp-port = port-number" 4
703 .IX Item "tcp-port = port-number"
704 Similar to \f(CW\*(C`udp\-port\*(C'\fR (default: \f(CW655\fR), but sets the \s-1TCP\s0 port number.
705 .IP "udp-port = port-number" 4
706 .IX Item "udp-port = port-number"
707 Sets the port number used by the \s-1UDP\s0 protocol (default: \f(CW655\fR, not
708 officially assigned by \s-1IANA\s0!).
709 .SH "CONFIG DIRECTORY LAYOUT"
710 .IX Header "CONFIG DIRECTORY LAYOUT"
711 The default (or recommended) directory layout for the config directory is:
712 .IP "gvpe.conf" 4
713 .IX Item "gvpe.conf"
714 The config file.
715 .IP "if-up" 4
716 .IX Item "if-up"
717 The if-up script
718 .IP "node-up, node-down" 4
719 .IX Item "node-up, node-down"
720 If used the node up or node-down scripts.
721 .IP "hostkey" 4
722 .IX Item "hostkey"
723 The private key (taken from \f(CW\*(C`hostkeys/nodename\*(C'\fR) of the current host.
724 .IP "pubkey/nodename" 4
725 .IX Item "pubkey/nodename"
726 The public keys of the other nodes, one file per node.
727 .SH "SEE ALSO"
728 .IX Header "SEE ALSO"
729 \&\fIgvpe\fR\|(5), \fIgvpe\fR\|(8), \fIgvpectrl\fR\|(8).
730 .SH "AUTHOR"
731 .IX Header "AUTHOR"
732 Marc Lehmann <gvpe@schmorp.de>