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 seperate 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 Reconfigures the multipaths. This should be triggered automati‐
148 cally after anyi hotplug event.
149 suspend map|multipath $map
151 Sets map $map into suspend state.
152 resume map|multipath $map
154 Resumes map $map from suspend state.
155 reset map|multipath $map
157 Reassign existing device-mapper table(s) use use the multipath
158 device, instead of its path devices.
159 reload map|multipath $map
161 Reload a multipath device.
162 fail path $path
164 Sets path $path into failed state.
165 reinstate path $path
167 Resumes path $path from failed state.
168 disablequeueing maps|multipaths
170 Disable queueing on all multipath devices.
171 restorequeueing maps|multipaths
173 Restore queueing on all multipath devices.
174 disablequeueing map|multipath $map
176 Disable queuing on multipathed map $map.
177 restorequeueing map|multipath $map
179 Restore queuing on multipahted map $map.
180 forcequeueing daemon
182 Forces multipathd into queue_without_daemon mode, so that
183 no_path_retry queueing will not be disabled when the daemon
184 stops.
185 restorequeueing daemon
187 Restores configured queue_without_daemon mode.
188 map|multipath $map setprstatus
190 Enable persistent reservation management on $map.
191 map|multipath $map unsetprstatus
193 Disable persistent reservation management on $map.
194 map|multipath $map getprstatus
196 Get the current persistent reservation management status of
197 $map.
198 map|multipath $map getprkey
200 Get the current persistent reservation key associated with $map.
201 map|multipath $map setprkey key $key
203 Set the persistent reservation key associated with $map to $key
204 in the prkeys_file. This key will only be used by multipathd if
205 reservation_key is set to file in /etc/multipath.conf.
206 map|multipath $map unsetprkey
208 Remove the persistent reservation key associated with $map from
209 the prkeys_file. This will only unset the key used by multipathd
210 if reservation_key is set to file in /etc/multipath.conf.
211 path $path setmarginal
213 move $path to a marginal pathgroup. The path will remain in the
214 marginal path group until unsetmarginal is called. This command
215 will only work if marginal_pathgroups is enabled and there is no
216 Shaky paths detection method configured (see the multipath.conf
217 man page for details).
218 path $path unsetmarginal
220 return marginal path $path to its normal pathgroup. 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 map $map unsetmarginal
226 return all marginal paths in $map to their normal pathgroups.
227 This command will only work if marginal_pathgroups is enabled
228 and there is no Shaky paths detection method configured (see the
229 multipath.conf man page for details).
230 quit|exit
232 End interactive session.
233 shutdown
235 Stop multipathd.
236
238 When compiled with systemd support two systemd service files are
239 installed, multipathd.service and multipathd.socket The multi‐
240 pathd.socket service instructs systemd to intercept the CLI command
241 socket, so that any call to the CLI interface will start-up the daemon
242 if required. The multipathd.service file carries the definitions for
243 controlling the multipath daemon. The daemon itself uses the
244 sd_notify(3) interface to communicate with systemd. The following unit
245 keywords are recognized:
246 WatchdogSec=
248 Enables the internal watchdog from systemd. multipath will send
249 a notification via sd_notify(3) to systemd to reset the watch‐
250 dog. If specified the polling_interval and max_polling_interval
251 settings will be overridden by the watchdog settings. Please
252 note that systemd prior to version 207 has issues which prevent
253 the systemd-provided watchdog from working correctly. So the
254 watchdog is not enabled per default, but has to be enabled manu‐
255 ally by updating the multipathd.service file.
256 OOMScoreAdjust=
258 Overrides the internal OOM adjust mechanism.
259 LimitNOFILE=
261 Overrides the max_fds configuration setting.
262
264 multipath(8), kpartx(8), sd_notify(3), system.service(5).
265
267 multipath-tools was developed by Christophe Varoqui <christophe.varo‐
268 qui@opensvc.com> and others.
269Linux 2016-10-27 MULTIPATHD(8)