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5.12. The multipathd Interactive Console and the multipathd Command

The multipathd -k command is an interactive interface to the multipathd daemon. Executing this command brings up an interactive multipath console, from which you can issue a number of commands. After executing this command, you can enter help to get a list of available commands, you can enter an interactive command, or you can enter CTRL-D to quit.
Note that you can issue any of the multipathd commands without entering interactive mode by using the following format.
# multipathd command argument
Some multipathd commands include a format option followed by a wildcard. You can display a list of available wildcards with the following command.
# multipathd show wildcards
The multipathd interactive console can be used to troubleshoot problems you may be having with your system. For example, the following command sequence displays the multipath configuration, including the defaults, before exiting the console.
# multipathd -k
> > show config
> > CTRL-D
The following command sequence ensures that multipath has picked up any changes to the multipath.conf,
# multipathd -k
> > reconfigure
> > CTRL-D
Use the following command sequence to ensure that the path checker is working properly.
# multipathd -k
> > show paths
> > CTRL-D
As of Red Hat Enterprise Linux release 6.8, the multipathd command supports new format commands that show the status of multipath devices and paths in "raw" format versions. In raw format, no headers are printed and the fields are not padded to align the columns with the headers. Instead, the fields print exactly as specified in the format string. This output can then be more easily used for scripting. You can display the wildcards used in the format string with the multipathd show wildcards command.
To following multipathd commands show the multipath devices that multipathd is monitoring, using a format string with multipath wildcards, in regular and raw format.
list|show maps|multipaths format $format
list|show maps|multipaths raw format $format
To following multipathd commands show the paths that multipathd is monitoring, using a format string with multipath wildcards, in regular and raw format.
list|show paths format $format
list|show paths raw format $format
The following commands show the difference between the non-raw and raw formats for the multipathd show maps. Note that in raw format there are no headers and only a single space between the columns.
# multipathd show maps format "%n %w %d %s"
name   uuid                              sysfs vend/prod/rev
mpathc 360a98000324669436c2b45666c567942 dm-0  NETAPP,LUN   

# multipathd show maps raw format "%n %w %d %s"
mpathc 360a98000324669436c2b45666c567942 dm-0 NETAPP,LUN