Moving & adding internal disks

[Josee Bourget-Thuma]

Hi!

I have a K580 with 4 internal disks.
3 are 4GB disks, the other a 2GB disk which HP highly recommends I get rid of.

I'm about to swap 2 of those disks with 2 x 18GB disk. I want to swap the boot disk and the 2GB disk.

This is an easy job with Ignite provided the SCSI ID's are assigned properly. This is not the case here and I'd like to rectify the matter while I'm installing my 2 disks.

Current config is:

vgroot on ID 4
vg01 on ID 5
vgora on ID 6 (which is the 2GB disk)
vg50 on ID 3

I'd like to change this to:

vgroot on ID 6
vg01 on ID 5
vgora on ID 4
vg50 on ID 3

I'd like to also change the vgroot and vgora names to more conventional names like vg00 and vg 02 while I'm at it too if possible.

I will have 2 ignite tapes before I perform this upgrade.

Would everyone be so kind and provide input as to how I should proceed? And if I'm just trying to do too much in one step?

Thanks to everyone for your suggestions!

Josee...

[James R. Ferguson · Accepted solution]

Hi Josee:

Changing the hardware SCSI IDs isn't necessary although you can do this too if you want.

Since you are changing your boot disk (vg00), use an Ignite recovery tape and take the opportunity to select the advanced installation options and resize your logical volumes according to your needs and tastes.

Use this, with current Ignite software to capture vg00:

# make_tape_recovery -x inc_entire=vg00 -I -v -a /dev/rmt/0mn

As for changing volume group names, this is easily done:

# unmount all associated logical volumes in the volume group to be changed

# vgchange -a n /dev/oldvgname

# vgexport ???m /tmp/vgoldname.map /dev/oldvgname

# mkdir /dev/newvgname

# mknod /dev/newvgname/group c 64 0x0X0000 (where X is a unique number not already used)

# vgimport ???m /tmp/vgoldmapfile /dev/newvgname /dev/dsk/

# vgchange -a y /dev/newvgname

Regards!

...JRF...

[Roger Baptiste]

hi,

ignite recovery can be reinstalled on any disk, irrespective of the id.

But, Since you would be physically accessing the disks for removing and adding process, you can change the scsi Id's at that time as per your requirements. The disk manual will show where the jumpers are for the ID change. Even the disks will have the marking for the dip switches. This should take care of the h/w part.

Once you do this, get into the bootadmin/isl prompt and do a search to see whether it shows the disks and the ids correctly.

Then, boot from the ignite tape, select the disk you want to install o/s on (18gb id 6)


<>

Yes, its possible. vg00 will anyway be taken care off by the install process.
As far as vg02 is concerned
when you import the vg, just import it as vg02.

<>

Actually, it is more than one step ;-)
Make the ignite tape;
do a vgimport of the non-vgroot volumes using
vgexport -v -m /tmp/vgxx.map vgxx
(copy these maps to a safe place outside the system , either on tape or to another system!).

Make sure which disks contain which VG, such that the scsiid change is smooth.

Hook the disks.

Reboot, install the o/s
and once you are done, copy the map files and do vgimport.

(another thing, since you are reigniting the o/s, the maps would already be there on the system!).

It should be a smooth process.
Just make sure you select the right disk when you install the o/S ! ;-)

HTH
raj

[paul courry]

Jim, I think Josee is wise to change his SCSI ID's.

The industry standard (which HP follows) is

6 boot
2 CD-ROM
0 tape

Adhering to the standard makes it *much* easier to work on the box. Non-standard SCSI Id's tend to cause mistakes by repair personnel, something you don't want at 2 am when you are wondering what the boot path is because the Core IO was just replaced.

[Deshpande Prashant]

HI
Remember to create the recovery tape (make_tape_recovery) with -I option, which causes the system recovery process to be interactive when booting from the tape.

Thanks.
Prashant.

[James R. Ferguson]

Hi Josee & Paul:

Thanks, Paul. Your point is very well taken. I agree.

Regards!

...JRF...

[Josee Bourget-Thuma]

Thanks to everyone for your input.

To emphasize the point on SCSI ID choice, I was talking to a trusted HP CE who confirmed to me that the SCSI chain would give ID 6 top priority for I/O... and on down the list with 5 being next then 4 and then 3. SCSI ID 7 belonging the the SCSI device itself would get top priority above all other devices of course.

Therefor, it seems to make sense to put vg00 on SCSI ID 6 with that concept in mind. Perhaps just a small performance gain here.

From all the notes, I'm proposing to go about my upgrade as follows:

1- Export everything to map files on a sub system except for vgroot.

2- Create ignite tape for vgroot only.

3- Recover vgroot on different hardware path as I follow allong with interactive boot from tape.
I'll make changes to my file systems at that time also. I should also be able to change vgroot to vg00 at that time.

4- vgimport my other 3 volumes groups one at a time allowing for name changes and desired distribution on the SCSI chain.

I'd be grateful if someone would point out if I missed anything. I know there's more than one way to skin this cat. This one seemed simpler.

Thanks a bunch!
Josee...