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lvm preferred_names not working

I am running RHEL 6.4 with EMC PowerPath.

The preferred_names line in my lvm.conf looks like

Code:

preferred_names = [ "^/dev/emcpower*", "^/dev/mpath/", "^/dev/mapper/mpath", "^/dev/sd" ]

My filter line in lvm.conf looks like:

Code:

filter = [ "a|/dev/emcpower.*|" "a|/dev/sd.*|" "a|/dev/cciss.*|" "a|/dev/mpath|" "r|.*|" ]

My root filesystem is on /dev/sda2 which is a local disk.

The pvs command reports:

Code:

# pvs

  Found duplicate PV 5MJOqv3uBda0vw1SPlr0SQmWOVGeZnxX: using /dev/sdc not /dev/emcpowerb

  Found duplicate PV EyhvDhjfh0M30sfIp1eRTzLqzOJ1J0hj: using /dev/sdd not /dev/emcpowera

  Found duplicate PV 5MJOqv3uBda0vw1SPlr0SQmWOVGeZnxX: using /dev/sdf not /dev/sdc

  Found duplicate PV EyhvDhjfh0M30sfIp1eRTzLqzOJ1J0hj: using /dev/sdg not /dev/sdd

  PV        VG    Fmt  Attr PSize  PFree

  /dev/sda2  rootvg lvm2 a--  277.97g 19.97g

  /dev/sdf  sanvg  lvm2 a--  100.00g    0

  /dev/sdg  sanvg  lvm2 a--  50.00g    0

Instead of /dev/sdf and /dev/sdg for sanvg, I want it to report /dev/emcpowera and /dev/emcpowerb. I was under the impression that setting up the filter line and the preferred_names line the way that I have would do this. Any help?

preferred_names = [ "^/dev/emcpower.*", "^/dev/mpath/", "^/dev/mapper/mpath", "^/dev/sd" ]

You're missing a '.'

I changed the preferred_names line to look like:

Code:

preferred_names = [ "^/dev/emcpower.*", "^/dev/mpath/", "^/dev/mapper/mpath" ]

Still not working.

My guess would be that lvm has no way to know that emcpowera, sdd and sdg are all the same device, and that the preferred_names processing isn't even coming into play.

I don't know enough about how the emc drivers work to be able to be more specific that that.

Preferred names did not worked for me also. Jus narrow your filter line.

BTW, I've switched from PowerPath to native Linux multipath.
I've always has a problem with kernel update while booting from PP device.
As from my experience, the only "added value" of PP is $1k/CPU.
Even that value added to EMC, not to you.

See this HOWTO LUNs on Linux using native tools.
Although, it built on NetApp example, I use same logic working with EMC devices.
You can check here: Boot from SAN RedHat 5.