3 disk rootvg in AIX

[vini14]

hello,
what if i have a rootvg with 3 disks, and if i run mirrrvg rootvg, what will happen?

 

[TSch]

Hey,

well according to the man pages, the following should happen:

By default, mirrorvg attempts to mirror the logical volumes onto any of
the disks in a volume group. If you wish to control which drives are
used for mirroring, you must include the list of disks in the input
parameters, physicalvolume. Mirror strictness is enforced.
Additionally, mirrorvg mirrors the logical volumes, using the default
settings of the logical volume being mirrored. If you wish to violate
mirror strictness or affect the policy by which the mirror is created,
you must execute the mirroring of all logical volumes manually with the
mklvcopy command.



I think you will get one additional copy and AIX chooses which disks are used ...

Regards,
Thomas

 

[AIXLogician]

If your rootvg is spread across three disks, 1st off its NOT a good practice. You need to get all those LV on to a single disk.

Say your 4th disk is large enough to accommodate all LV's, then you can either run

migratepv

orrun

 mklvcopy

.

Note: Migratepv will migrate the LV from one PV to another PV, but mklvcopy will mirror a LV to designated disk.