Mirror-UX question

[Juan Gonzalez_2]

I have a logical volume that has two mirror copies, see attachment. How can I delete one of those mirrored copies so that I only have one and not two mirroried copies of the crash logical volume.

[Michael Tully]

I can't read the attachment very well but I am assuming you wish to to remove the mirrored portion of the logical volume:

You need to run lvreduce. It will reduce the mirrored copies to only one. Select the disk you wish to reduce it from.

# lvreduce -m 1 /dev/vg00/crash /dev/dsk/cxtydz

[A. Clay Stephenson · Accepted solution]

Normally this would be a straightforward task but something is very strange here. You are running strict allocation but two mirrors appear to be on c2t6d0; that should not be possible under your allocation policy.

If we can assume that your c0t6d0 drive is okay then

lvreduce -m 1 /dev/vg00/crash /dev/dsk/c2t6d0

I would then do a 2nd vgreduce leaving everything the same except -m 0 which should leave you c0t6d0 disk intact. You should then be able to cleanly remirror using lvextend.

[A. Clay Stephenson]

In the spirit of "First, do no harm", I would get a backup before attempting anything else. Your 2 mirrors on the same disk under strict allocation really bothers me.

[Sunil Sharma_1]

Hi,

In strict allocation policy, it's not possible to have mirror on same disk, so there may be some problem.

You can try to run
#lvreduce -m 1 /dev/vgnn/lvolmm /dev/dsk/cxtydz


Sunil

[Fragon]

Hi, the attachment is not availabe to open!
I think you can use lvsplit to break all mirrors first, then use lvextend to make ONE-MIRROR mirror!
Please see the manpage for lvsplit & lvextend.
The lvmerge is another way to re-make the mirror, but please pay attention to the sequence of the lv_path!

-ux

[Michael Tully]

Now that I can read the attachment, I would recommend as suggested by Clay. Remove all mirrors and re-mirror to the correct secondary disk. There is not much point in mirroring to the same LUN. Use lvreduce and lvextend, do not use lvsplit.