Red Hat Bugzilla – Bug 1303770
Document new options of multipath command that add machine-readable/parseable output
Last modified: 2016-09-15 13:19:59 EDT
It looks as though I don't document the "multipathd show" command at all in the current DM-Multipath manual. Do you think we should add a table similar to this one for multipath:
If so, do you have suggestions for what we might include in that table?
For RHEL 7, we added a statement at the end of that table about using multipathd with wildcards -- which is odd because we don't otherwise talk about multipathd display commands, just multipath commands so I think I may have been confused when I added that. In any case, do we now add a similar sentence to the 6.8 version:
I don't know if we need to do anything like comprehensive documentation on the multipathd commands, but we should mention that there are a number of them, and they aren't just for troubleshooting. Most of the functionality of the multipath command also exists in multipathd commands. The document does point the reader to the help command, which is good. It would also be good to mention that you don't need to enter the interactive mode to issue these commands, simply running
# multipathd <command> <arguments>
will issue the command and print the results. We might want to call special attention to the format commands (and starting in RHEL-6.8 and RHEL-7.3, the raw format commands).
list|show maps|multipaths format $format
list|show paths format $format
list|show maps|multipaths raw format $format
list|show paths raw format $format
The difference between the raw and the regular versions is that with the raw versions, no headers are printed, and the fields are not padded to appear in nice columns. Instead they print out exactly as specified in the format string.
This is helpful for scripting.
The wildcards that are used in the format string can be shown with the wildcard command.
Also, starting in RHEL-7.3 and RHEL-6.9 (not the upcoming RHEL6 release, the one after it), there will be two additional commands
list|show pathgroups format $format
list|show pathgroups raw format $format
To display pathgroup information.