pvmove question

[Joel Shank]

I need to move off an older SAN LUN device to a new SAN LUN device. I have plenty of room to add the new device to the volume group.

My plan is to vgextend the volume group with the new LUN device and then do a pvmove from the old device to the new device, and then vgreduce the old device.

After reading the man page on pvmove, I do not see any requirement that the application using the volume group be down. Because of requirements, I need to have the application up and need to know if my plan is workable.

Has anyone done a similar move?

Thanks,
jls

[James R. Ferguson · Accepted solution]

Hi Joel:

The 'pvmove' can be done with the application up, but be advised that I/O will be very intensive and your application's access times will probably suffer.

Whatever you do, do not interrupt the process. A failed 'pvmove' can leave the volume in a nasty state.

BTW, 'pvmove' is essentially a mirror operation that you get for free regardless of whether or not you license the real MirrorDisk/UX.

Regards!

...JRF...

[Joel Shank]

Thank you, James.

That's what I thought, but I needed comfirmation from someone else.

jls

[Devender Khatana]

Hi,

Nothing seems wrong with the plan but execute this at some time when the application utilization is very less so that the users do not suffer.


Also if you have Mirror-Ux installed you can consider the mirror to new LUN and remove from old LUN option which also will take same time but with one more step but is safe.

HTH,
Devennder

[Joel Shank]

Just need verification that my plan was sound.