1MULTIPATHD(8) System Manager's Manual MULTIPATHD(8)
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6 multipathd - Multipath daemon.
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9 multipathd [-d|-k] [-s] [-v verbosity] [-B] [-w]
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12 The multipathd daemon is in charge of checking for failed paths. When
13 this happens, it will reconfigure the multipath map the path belongs
14 to, so that this map regains its maximum performance and redundancy.
15 This daemon executes the external multipath tool when events occur. In
17 turn, the multipath tool signals the multipathd daemon when it is done
18 with devmap reconfiguration, so that it can refresh its failed path
19 list.
20 In this Linux distribution, multipathd does not run unless a /etc/mul‐
22 tipath.conf file exists.
23
25 -d Foreground Mode. Don't daemonize, and print all messages to std‐
26 out and stderr.
27 -s Suppress timestamps. Do not prefix logging messages with a time‐
29 stamp.
30 -v level
32 Verbosity level. Print additional information while running mul‐
33 tipathd. A level of 0 means only print errors. A level of 3 or
34 greater prints debugging information as well.
35 -B Read-only bindings file. multipathd will not write to the
37 user_friendly_names bindings file. If a user_friendly_name
38 doesn't already exist for a device, it will use its WWID as its
39 alias.
40 -k multipathd will enter interactive mode. From this mode, the
42 available commands can be viewed by entering 'help'. When you
43 are finished entering commands, press CTRL-D to quit.
44 -n IGNORED. Use the option find_multipaths to control the treatment
46 of newly detected devices by multipathd. See multipath.conf(5).
47 -w Since kernel 4.14 a new device-mapper event polling interface is
49 used for updating multipath devices on dmevents. Use this flag
50 to force it to use the old event waiting method, based on creat‐
51 ing a separate thread for each device.
52
54 The following commands can be used in interactive mode:
55 list|show paths
57 Show the paths that multipathd is monitoring, and their state.
58 list|show paths format $format
60 Show the paths that multipathd is monitoring, using a format
61 string with path format wildcards.
62 list|show maps|multipaths
64 Show the multipath devices that the multipathd is monitoring.
65 list|show maps|multipaths format $format
67 Show the status of all multipath devices that the multipathd is
68 monitoring, using a format string with multipath format wild‐
69 cards.
70 list|show maps|multipaths status
72 Show the status of all multipath devices that the multipathd is
73 monitoring.
74 list|show maps|multipaths stats
76 Show some statistics of all multipath devices that the multi‐
77 pathd is monitoring.
78 list|show maps|multipaths topology
80 Show the current multipath topology. Same as 'multipath -ll'.
81 list|show topology
83 Show the current multipath topology. Same as 'multipath -ll'.
84 list|show map|multipath $map topology
86 Show topology of a single multipath device specified by $map,
87 for example 36005076303ffc56200000000000010aa. This map could be
88 obtained from 'list maps'.
89 list|show wildcards
91 Show the format wildcards used in interactive commands taking
92 $format.
93 list|show config
95 Show the currently used configuration, derived from default val‐
96 ues and values specified within the configuration file /etc/mul‐
97 tipath.conf.
98 list|show config local
100 Show the currently used configuration like show config, but lim‐
101 iting the devices section to those devices that are actually
102 present in the system.
103 list|show blacklist
105 Show the currently used blacklist rules, derived from default
106 values and values specified within the configuration file
107 /etc/multipath.conf.
108 list|show devices
110 Show all available block devices by name including the informa‐
111 tion if they are blacklisted or not.
112 list|show status
114 Show the number of path checkers in each possible state, the
115 number of monitored paths, and whether multipathd is currently
116 handling a uevent.
117 list|show daemon
119 Show the current state of the multipathd daemon.
120 add path $path
122 Add a path to the list of monitored paths. $path is as listed in
123 /sys/block (e.g. sda).
124 remove|del path $path
126 Stop monitoring a path. $path is as listed in /sys/block (e.g.
127 sda).
128 add map|multipath $map
130 Add a multipath device to the list of monitored devices. $map
131 can either be a device-mapper device as listed in /sys/block
132 (e.g. dm-0) or it can be the alias for the multipath device
133 (e.g. mpath1) or the uid of the multipath device (e.g.
134 36005076303ffc56200000000000010aa).
135 remove|del map|multipath $map
137 Stop monitoring a multipath device.
138 resize map|multipath $map
140 Resizes map $map to the given size.
141 switch|switchgroup map|multipath $map group $group
143 Force a multipath device to switch to a specific path group.
144 $group is the path group index, starting with 1.
145 reconfigure
147 Rereads the configuration, and reloads all changed multipath de‐
148 vices. This also happens at startup, when the service is reload,
149 or when a SIGHUP is received.
150 reconfigure all
152 Rereads the configuration, and reloads all multipath devices re‐
153 gardless of whether or not they have changed. This also happens
154 when multipath -r is run.
155 suspend map|multipath $map
157 Sets map $map into suspend state.
158 resume map|multipath $map
160 Resumes map $map from suspend state.
161 reset map|multipath $map
163 Reassign existing device-mapper table(s) use the multipath de‐
164 vice, instead of its path devices.
165 reload map|multipath $map
167 Reload a multipath device.
168 fail path $path
170 Sets path $path into failed state.
171 reinstate path $path
173 Resumes path $path from failed state.
174 disablequeueing maps|multipaths
176 Disable queueing on all multipath devices.
177 restorequeueing maps|multipaths
179 Restore queueing on all multipath devices.
180 disablequeueing map|multipath $map
182 Disable queuing on multipathed map $map.
183 restorequeueing map|multipath $map
185 Restore queuing on multipahted map $map.
186 forcequeueing daemon
188 Forces multipathd into queue_without_daemon mode, so that
189 no_path_retry queueing will not be disabled when the daemon
190 stops.
191 restorequeueing daemon
193 Restores configured queue_without_daemon mode.
194 map|multipath $map setprstatus
196 Enable persistent reservation management on $map.
197 map|multipath $map unsetprstatus
199 Disable persistent reservation management on $map.
200 map|multipath $map getprstatus
202 Get the current persistent reservation management status of
203 $map.
204 map|multipath $map getprkey
206 Get the current persistent reservation key associated with $map.
207 map|multipath $map setprkey key $key
209 Set the persistent reservation key associated with $map to $key
210 in the prkeys_file. This key will only be used by multipathd if
211 reservation_key is set to file in /etc/multipath.conf.
212 map|multipath $map unsetprkey
214 Remove the persistent reservation key associated with $map from
215 the prkeys_file. This will only unset the key used by multipathd
216 if reservation_key is set to file in /etc/multipath.conf.
217 path $path setmarginal
219 move $path to a marginal pathgroup. The path will remain in the
220 marginal path group until unsetmarginal is called. This command
221 will only work if marginal_pathgroups is enabled and there is no
222 Shaky paths detection method configured (see the multipath.conf
223 man page for details).
224 path $path unsetmarginal
226 return marginal path $path to its normal pathgroup. This command
227 will only work if marginal_pathgroups is enabled and there is no
228 Shaky paths detection method configured (see the multipath.conf
229 man page for details).
230 map $map unsetmarginal
232 return all marginal paths in $map to their normal pathgroups.
233 This command will only work if marginal_pathgroups is enabled
234 and there is no Shaky paths detection method configured (see the
235 multipath.conf man page for details).
236 quit|exit
238 End interactive session.
239 shutdown
241 Stop multipathd.
242
244 When compiled with systemd support two systemd service files are in‐
245 stalled, multipathd.service and multipathd.socket The multipathd.socket
246 service instructs systemd to intercept the CLI command socket, so that
247 any call to the CLI interface will start-up the daemon if required.
248 The multipathd.service file carries the definitions for controlling the
249 multipath daemon. The daemon itself uses the sd_notify(3) interface to
250 communicate with systemd. The following unit keywords are recognized:
251 WatchdogSec=
253 Enables the internal watchdog from systemd. multipath will send
254 a notification via sd_notify(3) to systemd to reset the watch‐
255 dog. If specified the polling_interval and max_polling_interval
256 settings will be overridden by the watchdog settings. Please
257 note that systemd prior to version 207 has issues which prevent
258 the systemd-provided watchdog from working correctly. So the
259 watchdog is not enabled per default, but has to be enabled manu‐
260 ally by updating the multipathd.service file.
261 OOMScoreAdjust=
263 Overrides the internal OOM adjust mechanism.
264 LimitNOFILE=
266 Overrides the max_fds configuration setting.
267
269 multipath(8), kpartx(8), sd_notify(3), system.service(5).
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272 multipath-tools was developed by Christophe Varoqui <christophe.varo‐
273 qui@opensvc.com> and others.
274Linux 2016-10-27 MULTIPATHD(8)