Linux LVM with EMC powerpath

How you plan to use Linux LVM with a multipathing software like EMc powerpath?
The trick is to mask out the non emcpower devices from LVM view. This is to ensure any path failure is handled by the multipathing software rather than LVM itself. The underlying path management complexity is offloaded to multipathing software. When the command pvscan, is issued you see only the emcpower devices.

You will have to enable the filter for accepting the emcpower devices and reject all the non emcpower devices inside /etc/lvm/lvm.conf file

filter =[ "a|/dev/emcpower.*|", "r|/dev/sd*|", "r|/dev/cdrom|" ]

Ensure only one filter is enabled.

Comments

  1. Jim GanongDecember 28, 2010 at 10:34 PM

    Thank you, Rupesh - this is just what I was looking for and needed! Appreciate it!

    ReplyDelete
  2. AnonymousJune 19, 2012 at 3:12 AM

    This is good stuff Rupesh, thanks. Do you know if the same is required when using native Linux multipathing?

    ReplyDelete
  3. AnonymousMarch 26, 2014 at 12:16 AM

    No, this rule isn't needed when using multipath. By the way, EMC doesn't recommend using multipath and powepath turned on simultaneously.

    Really good stuff. An old and useful post!

    ReplyDelete

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