1 .\" Copyright (c) 2010 The FreeBSD Foundation
2 .\" Copyright (c) 2010-2011 Pawel Jakub Dawidek <pawel@dawidek.net>
3 .\" All rights reserved.
5 .\" This software was developed by Pawel Jakub Dawidek under sponsorship from
6 .\" the FreeBSD Foundation.
8 .\" Redistribution and use in source and binary forms, with or without
9 .\" modification, are permitted provided that the following conditions
11 .\" 1. Redistributions of source code must retain the above copyright
12 .\" notice, this list of conditions and the following disclaimer.
13 .\" 2. Redistributions in binary form must reproduce the above copyright
14 .\" notice, this list of conditions and the following disclaimer in the
15 .\" documentation and/or other materials provided with the distribution.
17 .\" THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
18 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
21 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 .Nd configuration file for the
50 Configuration file is designed in a way that exactly the same file can be
51 (and should be) used on both HAST nodes.
52 Every line starting with # is treated as comment and ignored.
53 .Sh CONFIGURATION FILE SYNTAX
57 .Bd -literal -offset indent
63 compression <algorithm>
83 compression <algorithm>
90 # Resource-node section
99 # Resource-node section
110 Most of the various available configuration parameters are optional.
111 If parameter is not defined in the particular section, it will be
112 inherited from the parent section.
115 parameter is not defined in the node section, it will be inherited from
117 In case the global section does not define the
119 parameter at all, the default value will be used.
120 .Sh CONFIGURATION FILE DESCRIPTION
123 argument can be replaced either by a full hostname as obtained by
125 only first part of the hostname, or by node's UUID as found in the
130 The following statements are available:
131 .Bl -tag -width ".Ic xxxx"
132 .It Ic control Aq addr
134 Address for communication with
136 Each of the following examples defines the same control address:
137 .Bd -literal -offset indent
138 uds:///var/run/hastctl
139 unix:///var/run/hastctl
144 .Pa uds:///var/run/hastctl .
145 .It Ic listen Aq addr
147 Address to listen on in form of:
148 .Bd -literal -offset indent
149 protocol://protocol-specific-address
152 Each of the following examples defines the same listen address:
153 .Bd -literal -offset indent
162 Multiple listen addresses can be specified.
166 .Pa tcp4://0.0.0.0:8457
169 if kernel supports IPv4 and IPv6 respectively.
170 .It Ic replication Aq mode
172 Replication mode should be one of the following:
173 .Bl -tag -width ".Ic xxxx"
176 Report the write operation as completed when local write completes and
177 when the remote node acknowledges the data receipt, but before it
178 actually stores the data.
179 The data on remote node will be stored directly after sending
181 This mode is intended to reduce latency, but still provides a very good
183 The only situation where some small amount of data could be lost is when
184 the data is stored on primary node and sent to the secondary.
185 Secondary node then acknowledges data receipt and primary reports
186 success to an application.
187 However, it may happen that the secondary goes down before the received
188 data is really stored locally.
189 Before secondary node returns, primary node dies entirely.
190 When the secondary node comes back to life it becomes the new primary.
191 Unfortunately some small amount of data which was confirmed to be stored
192 to the application was lost.
193 The risk of such a situation is very small.
196 replication mode is currently not implemented.
199 Mark the write operation as completed when local as well as remote
201 This is the safest and the slowest replication mode.
204 replication mode is the default.
207 The write operation is reported as complete right after the local write
209 This is the fastest and the most dangerous replication mode.
210 This mode should be used when replicating to a distant node where
211 latency is too high for other modes.
214 replication mode is currently not implemented.
216 .It Ic checksum Aq algorithm
218 Checksum algorithm should be one of the following:
219 .Bl -tag -width ".Ic sha256"
221 No checksum will be calculated for the data being send over the network.
222 This is the default setting.
224 CRC32 checksum will be calculated.
226 SHA256 checksum will be calculated.
228 .It Ic compression Aq algorithm
230 Compression algorithm should be one of the following:
231 .Bl -tag -width ".Ic none"
233 Data send over the network will not be compressed.
235 Only blocks that contain all zeros will be compressed.
236 This is very useful for initial synchronization where potentially many blocks
238 There should be no measurable performance overhead when this algorithm is being
240 This is the default setting.
242 The LZF algorithm by Marc Alexander Lehmann will be used to compress the data
243 send over the network.
244 LZF is very fast, general purpose compression algorithm.
246 .It Ic timeout Aq seconds
248 Connection timeout in seconds.
253 Execute the given program on various HAST events.
254 Below is the list of currently implemented events and arguments the given
255 program is executed with:
256 .Bl -tag -width ".Ic xxxx"
257 .It Ic "<path> role <resource> <oldrole> <newrole>"
259 Executed on both primary and secondary nodes when resource role is changed.
261 .It Ic "<path> connect <resource>"
263 Executed on both primary and secondary nodes when connection for the given
264 resource between the nodes is established.
266 .It Ic "<path> disconnect <resource>"
268 Executed on both primary and secondary nodes when connection for the given
269 resource between the nodes is lost.
271 .It Ic "<path> syncstart <resource>"
273 Executed on primary node when synchronization process of secondary node is
276 .It Ic "<path> syncdone <resource>"
278 Executed on primary node when synchronization process of secondary node is
279 completed successfully.
281 .It Ic "<path> syncintr <resource>"
283 Executed on primary node when synchronization process of secondary node is
284 interrupted, most likely due to secondary node outage or connection failure
287 .It Ic "<path> split-brain <resource>"
289 Executed on both primary and secondary nodes when split-brain condition is
295 argument should contain full path to executable program.
296 If the given program exits with code different than
299 will log it as an error.
303 argument is resource name from the configuration file.
307 argument is previous resource role (before the change).
315 argument is current resource role (after the change).
323 GEOM provider name that will appear as
324 .Pa /dev/hast/<name> .
325 If name is not defined, resource name will be used as provider name.
328 Path to the local component which will be used as backend provider for
330 This can be either GEOM provider or regular file.
331 .It Ic remote Aq addr
333 Address of the remote
336 Format is the same as for the
339 When operating as a primary node this address will be used to connect to
341 When operating as a secondary node only connections from this address
346 can be used when the remote address is not yet known (eg. the other node is not
348 .It Ic source Aq addr
350 Local address to bind to before connecting to the remote
353 Format is the same as for the
358 .Bl -tag -width ".Pa /var/run/hastctl" -compact
359 .It Pa /etc/hast.conf
363 .It Pa /var/run/hastctl
364 Control socket used by the
366 control utility to communicate with the
371 The example configuration file can look as follows:
372 .Bd -literal -offset indent
376 listen tcp://2001:db8::1/64
379 listen tcp://2001:db8::2/64
386 remote tcp://10.0.0.2
389 remote tcp://10.0.0.1
394 local /dev/mirror/tanka
395 source tcp://10.0.0.1
396 remote tcp://10.0.0.2
399 local /dev/mirror/tankb
400 source tcp://10.0.0.2
401 remote tcp://10.0.0.1
414 .An Pawel Jakub Dawidek Aq pjd@FreeBSD.org
415 under sponsorship of the FreeBSD Foundation.