1MULTIPATHD(8)               System Manager's Manual              MULTIPATHD(8)
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NAME

6       multipathd - Multipath daemon.
7

SYNOPSIS

9       multipathd [-d|-k] [-s] [-v verbosity] [-B] [-w]
10

DESCRIPTION

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
16       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
21       In this Linux distribution, multipathd does not run unless a  /etc/mul‐
22       tipath.conf file exists.
23

OPTIONS

25       -d     Foreground Mode. Don't daemonize, and print all messages to std‐
26              out and stderr.
27
28       -s     Suppress timestamps. Do not prefix logging messages with a time‐
29              stamp.
30
31       -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
36       -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
41       -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
45       -n     IGNORED. Use the option find_multipaths to control the treatment
46              of newly detected devices by multipathd. See multipath.conf(5).
47
48       -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

COMMANDS

54       The following commands can be used in interactive mode:
55
56       list|show paths
57              Show the paths that multipathd is monitoring, and their state.
58
59       list|show paths format $format
60              Show the paths that multipathd is  monitoring,  using  a  format
61              string with path format wildcards.
62
63       list|show maps|multipaths
64              Show the multipath devices that the multipathd is monitoring.
65
66       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
71       list|show maps|multipaths status
72              Show  the status of all multipath devices that the multipathd is
73              monitoring.
74
75       list|show maps|multipaths stats
76              Show some statistics of all multipath devices  that  the  multi‐
77              pathd is monitoring.
78
79       list|show maps|multipaths topology
80              Show the current multipath topology. Same as 'multipath -ll'.
81
82       list|show topology
83              Show the current multipath topology. Same as 'multipath -ll'.
84
85       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
90       list|show wildcards
91              Show  the  format  wildcards used in interactive commands taking
92              $format.
93
94       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
99       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
104       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
109       list|show devices
110              Show all available block devices by name including the  informa‐
111              tion if they are blacklisted or not.
112
113       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
118       list|show daemon
119              Show the current state of the multipathd daemon.
120
121       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
125       remove|del path $path
126              Stop monitoring a path. $path is as listed in  /sys/block  (e.g.
127              sda).
128
129       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
136       remove|del map|multipath $map
137              Stop monitoring a multipath device.
138
139       resize map|multipath $map
140              Resizes map $map to the given size.
141
142       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
146       reconfigure
147              Reconfigures the multipaths. This should be triggered  automati‐
148              cally after anyi hotplug event.
149
150       suspend map|multipath $map
151              Sets map $map into suspend state.
152
153       resume map|multipath $map
154              Resumes map $map from suspend state.
155
156       reset map|multipath $map
157              Reassign  existing  device-mapper table(s) use use the multipath
158              device, instead of its path devices.
159
160       reload map|multipath $map
161              Reload a multipath device.
162
163       fail path $path
164              Sets path $path into failed state.
165
166       reinstate path $path
167              Resumes path $path from failed state.
168
169       disablequeueing maps|multipaths
170              Disable queueing on all multipath devices.
171
172       restorequeueing maps|multipaths
173              Restore queueing on all multipath devices.
174
175       disablequeueing map|multipath $map
176              Disable queuing on multipathed map $map.
177
178       restorequeueing map|multipath $map
179              Restore queuing on multipahted map $map.
180
181       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
186       restorequeueing daemon
187              Restores configured queue_without_daemon mode.
188
189       map|multipath $map setprstatus
190              Enable persistent reservation management on $map.
191
192       map|multipath $map unsetprstatus
193              Disable persistent reservation management on $map.
194
195       map|multipath $map getprstatus
196              Get the current  persistent  reservation  management  status  of
197              $map.
198
199       map|multipath $map getprkey
200              Get the current persistent reservation key associated with $map.
201
202       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
207       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
212       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
219       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
225       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
231       quit|exit
232              End interactive session.
233
234       shutdown
235              Stop multipathd.
236

SYSTEMD INTEGRATION

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
247       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
257       OOMScoreAdjust=
258              Overrides the internal OOM adjust mechanism.
259
260       LimitNOFILE=
261              Overrides the max_fds configuration setting.
262

SEE ALSO

264       multipath(8), kpartx(8), sd_notify(3), system.service(5).
265

AUTHORS

267       multipath-tools  was  developed by Christophe Varoqui <christophe.varo‐
268       qui@opensvc.com> and others.
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272Linux                             2016-10-27                     MULTIPATHD(8)
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