Query on Disk mirroring

[nibble]

hi guys, i have here a vg that is configure for Database files. its physical volumes were from xternal storage...

how will i know if this VG or physical volume is mirrored?

if mirrored, how can i see it?

[Victor Fridyev · Accepted solution]

Hi,

VG or physical volume can't be mirrored, but only logical volume.
You can check its mirror status by:
lvdisplay /dev/vgNN/lvolM|grep Mirror

HTH

[Naveej.K.A]

hi,

Two types of mirroring...
Software mirroring with the help of mirror-ux software and the hardware mirroring with the help of RAID card or RAID box.

Mirror-UX mirrors each logical volume and not the physical volumes or PVs. so lvdisplay -v /dev/vgxx/lvolxx will give you information regarding to which PVs the mirroring has been done.

Now you can check whether you have any RAID box installed with your unix box or any raid card installed or so. Check to see whether the database volume groups are on this RAID box.

hope this helps

with best wishes
Naveej

[nibble]

thank you very much..

ive tried to create a new pv for vg, using pvcreate and its states that the pv is already belong to a vg...when i issued a pvdislay to that devicepath, it states that that pv is not included or associated with a vg..

y is it? is there possibility that that pv is a mirror?

[Victor Fridyev]

I seen such a thing when connected used disks to a computer. There is a record somewhere in the disk where something shows that the disk belongs to some VG. In order to destroy the record one have to run
pvcreate -f /dev/rdsk/xxxxxx
but before the command running you have to be 100% sure that you don't destroy a needed information. The disk data can't be restored after the command by normal procedures.

HTH