topic Re: Setting Up For Disk Mirroring in Operating System - HP-UX

Setting Up For Disk Mirroring

Laurie A. Krumrey — Thu, 03 May 2001 11:34:37 GMT

Need Help with setting up new disks for Disk Mirror

I have 16 new LUN Disk (EMC Box) and I want to mirror to two existing Volume Groups
on the HP Disk Drive. See below Volume Groups and current existing file systems I want to mirror. Listed by each file group is the the
amount of new (EMC) Disks I want to assign to each each new disk mirroring file system on the EMC box:

1. vgarray0 Vol Group is Internal HP Disk
/db01 - 1 Lun Disk
/db03 - 1 Lun Disk
/db04 - 1 Lun Disk
/db05 - 1 Lun Disk
/db06 - 2 Lun Disk
/db07 - 4 Lun Disk
/db08 - 1 Lun Disk

2. VG01 volume groups is "HAS" Storage via SCSI
/db02 - 5 Lun Disk
--------
16 Lun Disk

Do I just go into SAM and assign the 16 disks, which I know how to do.
But I am not sure how to copy the from the internal Disk and the HAS (SCSI)
Storage to the new EMC Box.

Thank you,
Laurie

Re: Setting Up For Disk Mirroring

Thierry Poels_1 — Thu, 03 May 2001 11:42:20 GMT

Hi,
Mirror/UX allows you to mirror Logical Volumes to a spare place in the <> Volume Group.
So if you want to mirror to the other disk, you will need to put them in the same Volume Group.
regards,
Thierry Poels.

Re: Setting Up For Disk Mirroring

James R. Ferguson — Thu, 03 May 2001 11:51:45 GMT

Hi Laurie:

A couple of comments:

MirrorDisk/UX mirrors logical volumes within a volume group.

If you wish to establish the mirror arrangement at commandline, this is easily done. An simple, excellent guide can be found in the HP-UX System Administration Tasks manual:

http://docs.hp.com/hpux/onlinedocs/B2355-90672/B2355-90672.html

This guide discusses both SAM and commandline setups. The data is actually copied to a mirrored volume as a part of the mirror setup process ('lvextend -m').

...JRF...

Re: Setting Up For Disk Mirroring

boley janowski — Thu, 03 May 2001 12:15:22 GMT

here is part of my vgdisplay -v vg00 to give you an idea of the way the disk are added to the same vg, notice the the space on the MIRROR group is allocated along with the INTERNAL group, but the BCV group is not, I have a job set the syncs up the mirrors and then splits them nightly.

LV Size (Mbytes) 1200
Current LE 300
Allocated PE 600
Used PV 3

LV Name /dev/vg00/lvol6
LV Status available/syncd
LV Size (Mbytes) 800
Current LE 200
Allocated PE 400
Used PV 2

--- Physical volumes ---
PV Name /dev/dsk/c4t5d0
PV Status available
Total PE 1023
Free PE 0
Autoswitch On

PV Name /dev/dsk/c4t6d0
PV Status available
Total PE 1023
Free PE 0
Autoswitch On

PV Name /dev/dsk/c1t0d0
PV Status available
Total PE 2170
Free PE 124
Autoswitch On

PV Name /dev/dsk/c1t1d0
PV Status available
Total PE 2170
Free PE 2170
Autoswitch On

--- Physical volume groups ---
PVG Name INTERNAL
PV Name /dev/dsk/c4t5d0
PV Name /dev/dsk/c4t6d0

PVG Name MIRROR
PV Name /dev/dsk/c1t0d0

PVG Name BCV
PV Name /dev/dsk/c1t1d0

hope this helps some, the links provided will help with setting something simular, if not ask.

good luck

Re: Setting Up For Disk Mirroring

Tim D Fulford — Thu, 03 May 2001 13:42:48 GMT

This does not answer your question, but may be of some use.

Why are you trying to mirror disks on an EMC? EMC (as far as my experience has been) always do internal mirroring (or RAID5). That's one of the reasons why they cost so much!

I'd make sure you disks are not mirrored before doing LVM mirroring.

o If they are not mirrored then what James said is probably what you want.
o If they are mirrored remember to turn off bad block allocation on EACH LV on the EMC.
# lvchange -r N /dev//.

Cheers

Tim

Re: Setting Up For Disk Mirroring

Laurie A. Krumrey — Thu, 03 May 2001 13:44:20 GMT

My problem is that my current setup is this:

VG01 - uses 3 8G LUN Disks
vgarray0 - uses 4 10G LUN Disks

And my new EMC Box only has 4G LUN Disks
available. I need to mirror VG01 and
vgarray0 to my EMC Box with 4G LUN Disks
I have tons of 4G LUN Disk availabe.

I thought you had to setup for disk mirroring
with the exact same size of LUN Disk.

Can you mix and match and if so how? What
are the rules?

Laurie

Re: Setting Up For Disk Mirroring

Thierry Poels_1 — Thu, 03 May 2001 13:57:13 GMT

Hi again,
as I mentioned before Mirror/UX will mirror Logical Volumes in a Volume Group, it does not mirror disks.
So if you want to mirror a Logical Volume the mirror copy will be placed somewhere (you have some control over the 'somewhere') in the Volume Group just like you would create a new logical volume. In other words the mirror might be completely on one disk, or might be spread over several disks; and if you have one logical volume sized 9GB on a 9GB disk it might/can be mirror to whatever combination of other disks.
regards,
Thierry.

Re: Setting Up For Disk Mirroring

Pedro Sousa — Thu, 03 May 2001 14:19:32 GMT

an easy way to copy the data from the internal disks to EMC is:
vgextend <-g pvgname>
pvmove

Then you can only remove the "old" internal disks with vgreduce.
good luck.