[dm-devel] different LUN numbers under the same dm device

[Brian Bunker]

Our company produces a multiple port Fibre Channel storage array. We are continually plagued by this problem. We get a dm device which combines paths for different LUN's. We would like to understand why this is happening. Wouldn't this problem almost certainly lead to a data corruption?

Thanks,
Brian

3624a93700a14254d729923840001000b dm-11 PURE,FlashArray
size=500G features='0' hwhandler='0' wp=rw
`-+- policy='round-robin 0' prio=1 status=active
  |- 1:0:0:12 sde  8:64   failed faulty running
  |- 0:0:0:12 sdd  8:48   failed faulty running
  |- 0:0:0:10 sdar 66:176 active ready  running
  `- 1:0:0:10 sdba 67:64  active ready  running

Of the 4 paths to dm-11, we can see two paths are for LUN 10 and the other two are for LUN 12. We have 24 other dm devices which have only the expected 2 paths. 

Brian Bunker
brian at purestorage.com