topic Re: mirroring logical volume in Operating System - HP-UX

mirroring logical volume

bitou — Sat, 26 Mar 2011 17:30:09 GMT

hi,
i have created a logical volume lvol11 and i forget to choose the mirroring option from sam. in addition the logical volume is mounted in /test
my question is how i can mirroring the logical volume?,plz provide me the steps by details.

Re: mirroring logical volume

James R. Ferguson — Sat, 26 Mar 2011 18:55:28 GMT

Hi:

You can simply mirror your logical volume now. This is often done when filesystems are mounted and in-use. Simply do:

# lvextend -m 1 /dev/vgNN/lvol11

...or if you want to target a particular disk:

# lvextend -m 1 /dev/vgNN/lvol11 /dev/dsk/cXtYdZ

Regards!

...JRF...

Re: mirroring logical volume

bitou — Sat, 26 Mar 2011 20:43:52 GMT

Hi:
thanks for yr reply, but i have mirroring the boot disk, what is prefered to do?
# lvextend -m 1 /dev/vg00/lvol11

# lvextend -m 1 /dev/vg00/lvol11 /dev/dsk/cxtYdZ

bitou

Re: mirroring logical volume

James R. Ferguson — Sat, 26 Mar 2011 21:44:12 GMT

Hi (again):

> but i have mirroring the boot disk, what is preferred to do?

In my opinion it never hurts to be explicit.

# lvextend -m 1 /dev/vg00/lvol11 /dev/dsk/cxtYdZ

...where 'cXtYdz' is the disk on which you want to create the mirror.

Regards!

...JRF...

Re: mirroring logical volume

Ismail Azad — Mon, 28 Mar 2011 05:04:28 GMT

Hi,

As JRF has rightly mentioned, it doesn't hurt to be "specific" but just in case you have only one boot disk and that contains all your essential O.S lvols and one extra P.V in that V.G and you have the default allocation policy... there is pretty much only one place that lvol go. However, it is always best to have less than three disks in your root volume group.

Regards
Ismail Azad

Re: mirroring logical volume

P Arumugavel — Mon, 28 Mar 2011 08:42:37 GMT

Hi,

Logical volumes in root VG has been allocated with strict policy. Strict policy will not allow to sit the mirror extents on the same disk. If you have more than 2 disk in your VG, then specify the pv path, else you can do without specifying the pv path.

Rgds...

Re: mirroring logical volume

abir chowdhury — Wed, 30 Mar 2011 05:35:56 GMT

please umount /test if is a base JFS

#lvextend -m 1 /dev/vg00/lvol1 /dev/dsk/c1t0d0

Re: mirroring logical volume

Torsten. — Wed, 30 Mar 2011 06:23:34 GMT

No need to unmount anything if you want to mirror ...

Re: mirroring logical volume

Viktor Balogh — Wed, 30 Mar 2011 12:26:27 GMT

... and he isn't able to umount it since it has turned out that it's about the root disk.

Re: mirroring logical volume

Abid Iqbal — Thu, 31 Mar 2011 07:11:53 GMT

Hi,
Just run the below commands and it is done

# lvextend -m 1 /dev/vg00/lvol1
# lvlnboot -b /dev/vg00/lvol1 /dev/vg00