Dm-Multipath Administration And Troubleshooting; Multipath Command Output - Red Hat ENTERPRISE LINUX 5.1 DM MULTIPATH Configuration And Administration Manual

Chapter 5.
DM-Multipath Administration and
Troubleshooting
This chapter will provide information on administering DM-Multipath on a running system. It includes
sections on the following topics:

• Multipath Command Output

• Multipath Queries with multipath Command
• Multipath Command Options
• Multipath Queries with dmsetup Command
• Troubleshooting with the multipathd Interactive Console
5.1. Multipath Command Output
When you create, modify, or list a multipath device, you get a printout of the current device setup. The
format is as follows.
For each multipath device:
action_if_any: alias (wwid_if_different_from_alias) [size][features]
[hardware_handler]
For each path group:
\_ scheduling_policy [path_group_priority_if_known]
[path_group_status_if_known]
For each path:
\_ host:channel:id:lun devnode major:minor [path_status]
[dm_status_if_known]
For example, the output of a multipath command might appear as follows:
mpath1 (3600d0230003228bc000339414edb8101) [size=10 GB][features="0"]
[hwhandler="0"]
\_ round-robin 0 [prio=1][active]
\_ 2:0:0:6 sdb 8:16 [active][ready]
\_ round-robin 0 [prio=1][enabled]
\_ 3:0:0:6 sdc 8:64 [active][ready]
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