Removing mirrored root disk

[rajeshk]

Hi,
I need to remove the mirrored root disk which i had configured. Can any one guide me the steps to remove the mirrored root disk.

Note: Does the mirroring will cause any performance issue. Because i had implemented one month before. After that only the compilation takes long time to complete.

Thanks
K.Rajesh

[Michael Tully]

Hi,

To remove the mirror you need to lvreduce each volume from the mirror. you can easily put this into a script as well

Assuming you have only one mirror volume and your disk is /dev/dsk/c2t6d0

for LVOL in /dev/vg00/lv*
> do
> echo $LVOL
> lvreduce -m 0 $LVOL
> vgreduce /dev/vg00 /dev/dsk/c2t6d0
> done

HTH
Michael

[Rajeev Shukla]

Hi Rajesh,

As far as performance is concerned only writing of data will take long time and dearing wont be effected. But i guess compilation should not have any problem.
Ok now to remove the mirror

First you'll have to reduce all the mirror
lvreduce -m 0 /dev/vg00/lvol1 /dev/dsk/c0...(the disk you want to remove)
do this for lvols mirror on that disk.
and then do vgreduce
vgreduce /dev/vg00 /dev/dsk/c0..(the disk you want to remove)

Cheers
Rajeev

[vishal_6]

Hi Rajesh,

Regarding the mirroring performance Vg00
mirror across the another controler should not degrade the performance unless the disks
are of different speed.if you are talking about application file systems then Bottleneck could be different disk speed,
pci, disk controler cache, how the disks
has been configured and the no of disk array.

As well depends on whether its read intensive
or write intensive.

Hope this helps.

[Thayanidhi]

Hi,

Assume /dev/dsk/c1t5d0 and /dev/dsk/c2t5d0 are
mirrored. If you want to remove mirror from
/dev/dsk/c2t5d0

lvreduce -m 0 /dev/vg00/lvol? /dev/dsk/c2t5d0

repeat for all LVs.

vgreduce /dev/vg00 /dev/dsk/c2t5d0

Since you have noticed the slowness, please make sure the mirrored pairs are from different
disk/controller. The recomended way of doing
is to create Contiguous and strict alocation.
You can change it using lvchange command.

Regards

TT

[Ravi_8]

Hi, rajesh

to reduce the mirrored root disk.

#lvreduce -m 0 /dev/lvolx (x is the lvol number)
repaer the same for all lvol in that disk.
#vgreduce /dev/vg00 /dev/rdsk/cxtxdx
(cxtxdx is the mirrored disk)

Mirroing doesn't cause any problem, since it's RAID 1, performance slightly reduces as the I/O(r/w to the mirrored disk) increases