1.5. Displaying multipath topology

Procedure

1. Display the multipath device topology:

   # multipath -ll
   mpatha (3600d0230000000000e13954ed5f89300) dm-4 WINSYS,SF2372
   size=233G features='1 queue_if_no_path' hwhandler='0' wp=rw
   `-+- policy='service-time 0' prio=1 status=active
     `- 6:0:0:0 sdf 8:80 active ready running

   The output can be split into three parts. Each part displays information for the following group:

   • Multipath device information:

     • mpatha (3600d0230000000000e13954ed5f89300): alias (wwid if it’s different from the alias)
     • dm-4: dm device name
     • WINSYS,SF2372: vendor, product
     • size=233G: size
     • features='1 queue_if_no_path': features
     • hwhandler='0': hardware handler
     • wp=rw: write permissions

   • Path group information:

     • policy='service-time 0': scheduling policy
     • prio=1: path group priority
     • status=active: path group status

   • Path information:

     • 6:0:0:0: host:channel:id:lun
     • sdf: devnode
     • 8:80: major:minor numbers
     • active: dm status
     • ready: path status

     • running: online status

       For more information about the dm, path and online status, see Path status.

       Other multipath commands, which are used to list, create, or reload multipath devices, also display the device topology. However, some information might be unknown and shown as undef in the output. This is normal behavior. Use the multipath -ll command to view the correct state.

       注意

       In certain cases, such as creating a multipath device, the multipath topology displays a parameter, which represents if any action was taken. For example, the following command output shows the create: parameter to represent that a multipath device was created:

       create: mpatha (3600d0230000000000e13954ed5f89300) undef WINSYS,SF2372
       size=233G features='1 queue_if_no_path' hwhandler='0' wp=undef
       `-+- policy='service-time 0' prio=1 status=undef
         `- 6:0:0:0 sdf 8:80 undef ready running