how do I remove devices from powerpath?

[Jay_122]

Hi,
I migrated data from our DMX to our clarion and would like to reclaim the DMX luns. The issue I am having is that no matter what I do, power path see the luns as "active" and "alive". I do not want to pull the rug out from under the OS so I have not tried unmasking them from the FA's.

Any help is welcome.

[Khairy]

hi jay,

how do u migrate the stuff from dmx to clariion. Filesys to filesys copy or lvm DRD?

Rgds

[Jay_122]

It was filesys to filesys. I have removed rhe LV's and VG's Now I need to remove the luns.

[Frank_W]

First you have to remove the LUN´s from the VolumeGroup configuration.
Then you can remove the LUN from the array´s storage group and the LUN will get the powerpath-status "dead" (ioscan will say NO-HW)

With the command "powermt check" you can then remove the non-existing LUN´s from the powerpath-config. This can take some minutes.
After all dead links are removed, use "powermt save" to save the new config.

[Khairy]

hi jay,

frank is right.

You can clear the vg by deactivate and export or vgremove. Make sure you umount all the old logical volumes.
# vgchange -a n vgname
# vgexport vgname

Then you could remove the disk devices.
# rmsf -a /dev/dsk/c#t#d#

You could remove DMX LUNs :
# powermt remove force dev=c#t#d#

Rgds

[Jay_122]

Removed the device file as suggested with rmsf -a but this caused the I/O path in PP to become unknown so I could not do the remove with a force.

The LUNS I am looking to remove are on the DMX not the clarion (I have no issues removing clarion LUNS). The only way I have found to make this work is to unmask the LUN from the FA (this will cause NO_HW) and the PP device will have a dead status. I can then run a powermt check to remove the dead paths.

I do not like this approach and was hoping for a better way. Is this the only way to do this?

[Rita C Workman]

I'll presume your going to use those DMX disk again. Once you remove the masking, then unmap the disk as well. That way you always know, for sure, they are not in use when you want to set them up again.

Another thing you can do if you do not want to "force" things.

After unmasking & un-mapping run ioscan -fnC disk > ioscan.disk. If you keep old ioscan files you can compare and see the reduction in hardware. Plus removing using rmsf command.
For Powerpath, you might run:
powermt check
>>>when it asks about killing dead connections, say "y".

Just a thought,
Rgrds,
Rita

[Frank_W · Accepted solution]

Hallo Jay,

I am working with clariions, but it shut be no difference for powerpath if you are using DMX.

1.) remove the LUN from the VG-config
2.) in the DMX: make the LUN invisible for your server ( "unmask the LUN from the FA" )
3.) when the LUN isnt visible anymore ( dead and NO_HW ): "powermt check" ( launch as often til all LUNs are removed );
4.) "powermt save"

I dont know what happens with "powermt remove".
If you get errors because of the missing devicefiles, you can reinstall them with "insf"