topic Re: Remove the Mirrored Root Disk in Operating System - HP-UX

Remove the Mirrored Root Disk

P Vel — Fri, 25 Feb 2011 05:17:25 GMT

Hi All,

I need to remove the mirroed root disk. Because this server has already enough reduntacy for the root disk as it has an in-built SmartArray RAID Controller with RAID level 1. Please help me with the procedure how to remove the mirrored disk from root VG and use for another VG

Thanks in advance...

Re: Remove the Mirrored Root Disk

nijokj — Fri, 25 Feb 2011 06:20:59 GMT

first you need to lvreduce all the mirrord lvs

Remove mirror copies of logical extents of a logical volume from the
physical volume /dev/dsk/c1t0d0:
eg:lvreduce -m 0 /dev/vg01/lvol4 /dev/dsk/c1t0d0

lvreduce -m 0 /dev/vg00/lvname
Remove physical volume /dev/dsk/c0t1d0 from volume group /dev/vg01:

eg:vgreduce /dev/vg00 /dev/dsk/c0t1d0

Re: Remove the Mirrored Root Disk

P Vel — Fri, 25 Feb 2011 06:23:12 GMT

Thanks.

How will I remove those 3 partions (EFI, HPUX, HPSP) from the disk?

Re: Remove the Mirrored Root Disk

Shibin_2 — Fri, 25 Feb 2011 06:26:10 GMT

Once you removed the disk from VG, you can do pvcreate -f /dev/rdsk/cxtydz to remove all data and can reuse for any VG.

You may read this. Good for understanding.

When_Good_Disks_Go_Bad_WP
http://bizsupport2.austin.hp.com/bc/docs/support/SupportManual/c01911837/c01911837.pdf

Re: Remove the Mirrored Root Disk

P Vel — Fri, 25 Feb 2011 06:31:46 GMT

Yes Shibin,

But system's ioscan output still shows all three partion in disk..

Re: Remove the Mirrored Root Disk

P Vel — Fri, 25 Feb 2011 06:38:42 GMT

I had already run # idisk -R disk

But how to remove the device special file?

Re: Remove the Mirrored Root Disk

Shibin_2 — Fri, 25 Feb 2011 06:41:26 GMT

First you haven't told, what is your OS version.

Do you want it to be completely taken out from the system ?

Re: Remove the Mirrored Root Disk

P Vel — Fri, 25 Feb 2011 06:46:14 GMT

B.11.23

No... I need to use this disk for an another VG. But I want to remove those partions. But it is done with #idisk -R.

Now I want to remove those device files. Should I need to run rmsf for all individual special files (for both block/character) or any other way?

Re: Remove the Mirrored Root Disk

nijokj — Fri, 25 Feb 2011 07:01:10 GMT

yes , you should run rmsf

eg: rmsf -H

Re: Remove the Mirrored Root Disk

Shibin_2 — Mon, 28 Feb 2011 02:33:01 GMT

You need to use the disk on another VG on same server? If it will be using for same server, why you want to remove the special files? You just need to remove the LUN from VG, do pvcreate with -f, then add to another VG you required.

Re: Remove the Mirrored Root Disk

qijian_li — Mon, 28 Feb 2011 03:57:03 GMT

Firstly, an in-built SmartArray RAID Controller with RAID level 1 also need two disks to realise it with sasmgr command. you can conferm the raid 1 as followed command:
sasmgr get_info -D /dev/sasd0 -q raid

next step to remove the mirrored root disk:
lvreduce, vgreduce, idisk, pvcreate...

email:qijian_li@hpsupport.com

Re: Remove the Mirrored Root Disk

Torsten. — Mon, 28 Feb 2011 06:16:48 GMT

Don't get confused, even if the partitions on the disks are deleted, the device files are still shown until they are removed too.