Mirroring itanium boot drive

[Timothy P. Jackson]

I have a new itanium and have installed HP-UX 11i Version 3. I am looking for instructions on how to mirror the boot drive. Obviously it is different then HP-UX 11i Version 1

Any help would be greatly appreciated!!

Tim

[James R. Ferguson]

Hi Tim:

You very well may have a Smart Array controller and hence a hardware RAID mirror.

You might want to see what is returned by:

# ioscan -kfnC disk

# sasmgr get_info -D /dev/sasd0 -q raid

An invaluable document, otherwise is this (which also discusses the differences between mirroring vg00 on PA-RISC and Itanium:

http://docs.hp.com/en/5991-1236/When_Good_Disks_Go_Bad_WP.pdf

Regards!

...JRF...

[Michael Steele_2]

"(* EFI *)
diskinfo c2t0d0s1,2,3 "
"vi /tmp/partitionfile
11.23
2
EFI 100 MB
HPUX 100%

> 11.23
3
EFI 500 MB
HPUX 100% -or- xxxxmb
HPSP 400mb"
idisk -wf /tmp/partitionfile disk
idisk -p disk
insf -e
pvcreate -B disk,s2
mkboot -e -l disk
vgextend vg00 disk,s2
lvextend -m 1 lvol1 disk,s2 (* and all other lvols *)
lvlnboot -r -b -s -s (* lvol3,1,2,2 *)
efi_ls -d rdsk/disk,s1
"efi_cp -d rdsk/primary_disk,s1 -u /EFI/HPUX/AUTO /tmp/AUTO
(* copy AUTO file from pri to /tmp/AUTO *)"
"efi_cp -d rdsk/alterna_disk,s1 -u /EFI/HPUX/AUTO /tmp/AUTO
(* copy AUTO file from pri to /tmp/AUTO *)"
reboot

[Michael Steele_2]

page 26

[Torsten.]

If the system supports this, do yourself a favour and create a hardware RAID - this is possible with most current servers. Please tell what model you have.

[Raj D. · Accepted solution]

Timothy,

I use a small script and it helps to mirror the root disk quickly,
You can try this small program, (mirror.v3_hp-ux_11.31 ) , cereful while specifying the source and target,


Inside you have to change Target (the new disk to be mirrored), and Source (The existing boot disk).

#---------------------
TARGET_DSK="diskXX"
SOURCE_DSK="diskYY"
#---------------------


Cheers,
Raj.

[Torsten.]

Just to add this - it could be really painful to replace a SAS disk in a LVM mirror - avoid this if possible!

[James R. Ferguson]

Hi (again):

Posting a PDF file that was stored off 3-years ago when a current version is freely available on the HP web makes little sense to me.

...JRF...

[Torsten.]

I did not read all the attachments here, but I know the procedures for mirroring in 11.23 and 11.31 are slightly different.

http://docs.hp.com/en/5992-6576/ch03s04.html#cbddaicd



Tim, what server model do you have?

[Timothy P. Jackson]

The "model" command returns the following

ia64 hp server rx3600

[Torsten.]

The rx3600 has either the built-in SAS controller (always) or an optional smartarray RAID controller.

With the built-in you can configure a mirrored pair of disks for boot disk. Unfortunately you cannot migrate online, but you need to take a backup and restore (or mirror to a third drive).


I would take an ignite backup, configure the hardware RAID and restore the image. This take less than 1 hour.


It will be a complicated procedure to replace a SAS disk in a LVM mirror configuration, believe this. If you reboot the server with a dead disk, it will get more complicated.

So take the hardware mirror option.

If you have questions, please ask.

[Timothy P. Jackson]

So it would be better to use hardware mirroring for the boot drives and then use normal MirrorDisk-UX for the rest of the drives?

I have never done hardware mirroring, is there a document for doing this or do you have a proceedure I could use?

[Torsten.]

The built-in controller can do hardware mirror for 2 pairs of disks only.

The procedure is quite easy and mentioned on http://docs.hp.com -> server hardware -> your server -> built-in sas controller.

While building the RAID all data will get lost!

[Torsten.]

The guide:

http://docs.hp.com/en/5900-0112/index.html

[Michael Steele_2]

Hi

In case of new generation of Integrity systems, there are SAS HBAs and SAS Smart arrays HBAs with specific RAID levels are being offered and their use is depends on the OS platform to be used on them. You can see what RAID controller installed on the server when you power on the server and system f/w detects it.

Take a look at the specs of then new servers.
http://h20341.www2.hp.com/integrity/cache/331424-0-0-225-121.html

http://h71028.www7.hp.com/ERC/downloads/4AA0-6159ENW.pdf

To configure the Integrated Mirror is you use EFI utilities as mentioned at
http://docs.hp.com/en/AB464-9001B/ch09s02.html#babhihch

You can manage SAS storage using "sasmgr" utility as mentioned at
http://docs.hp.com/en/J6369-90045/ch04s02.html

[Torsten.]

Michael, you should update your bookmarks. Most links result in a "Document removed from the site". It lists the new link if your link is the predecessor, otherwise it will give an error only. I know, this is somehow ***@!"Q!*** ...

[Michael Steele_2]

Geez, sorry, I just copied and pasted.

[Torsten.]

I know, I do the same from my repository usually. Unfortunately the links will change if the documents are updated. So I usually have a lot of dead links only.


:-(

[Raj D.]

Tim,
Also it would be a good idea to *remove* the (Hardware raid) integrated mirror volume . And configured softwre raid using LVM mirroring from OS and it works fine like a normal server. And all the disk space will be available.
If there are 8 disk on the 3600 , you can assign 2 disk for vg00 mirroring , remaining 6 disk can be used for other purpose completely.


* check out the document to remove Integrated mirror volume (Hardware raid):
[ Adding viewing deleting SAS raid controller -.doc atached ]

* To note: system needs to be rebooted, all the data on the disks will be erased .
* This is useful for new installations or during a fresh os installation .

Cheers,
Raj.

[Torsten.]

@Raj D.:

I'm trying to give arguments why hardware RAID is better than LVM mirror with this system (I can tell you why, if you want), but why do you suggest the opposite now???

[Timothy P. Jackson]

I am kind of confused......

should I use hardware mirroring for the boot drive and lvm mirroring for the rest?

[Torsten.]

If you want to use all 8 disks it is probably the best idea to get a P400 smartarray and configure some logical drives (RAID 1, 5 or whatever).

The problem is, if you swap a bad drive that is e.g. c4t0d0 it will become c4t1d0 and your config won't match this. You can fix this, but many steps are needed. With hardware RAID, you just need to swap the disk and you are done.

[Timothy P. Jackson]

Thanks Torsten and Raj!

I am going to mirror the boot drive using hardware mirroring. this will leave me with 6 drives left in which I will use MirrorDisk-UX to mirror.

Does this sound like a logical path with out purchasing an array card?

[Torsten.]

You can create 2 pairs of mirrored disks.

It is possible to manage a disk replacement with sas disks in LVM mirror configuration, but you need to redirect the device files.

Unfortunately my links are dead, I will research ...

[Torsten.]

Here it is, but this works only without a reboot with a bad disk! After a reboot the old device is gone and can't be redirected.

http://docs.hp.com/en/5900-0112/ch04s05.html