topic Re: pvcreate disk on SAN in Operating System - HP-UX

pvcreate disk on SAN

Kelly_49 — Thu, 01 Jul 2004 09:01:54 GMT

HP-UX B.11.00 U 9000/800

When I run pvcreate I do not get a "created successfully" message back.

All the special files are created when insf -e is ran and they show up as CLAIMED. vpath is created when cfgvpath is ran.

I have tried vgextend to no avail.

diskinfo returns:
SCSI describe of /dev/rdsk/c40t0d3:
vendor: IBM
product id: 2105F20
type: direct access
size: 0 Kbytes
bytes per sector: 0

My SAN person has checked the SAN side many times.

Any suggestions????

Re: pvcreate disk on SAN

Fabio Ettore — Thu, 01 Jul 2004 09:07:35 GMT

Hi,

in my mind came soon a question: if you don't get "created successfully" what do you get?

Maybe it fails because it is already assigned to another volume group.

Best regards,
Ettore

Re: pvcreate disk on SAN

Dietmar Konermann — Thu, 01 Jul 2004 09:07:36 GMT

As long as diskinfo returns "size: 0 Kbytes" your SAN/Storage folks have some work to do... maybe it's important WHAT to check, not how often. :)

Best regards...
Dietmar.

Re: pvcreate disk on SAN

Todd McDaniel_1 — Thu, 01 Jul 2004 09:10:36 GMT

I have run into the rare occasion where the disk is set to read only and can't be modified with LVM commands...

Have your EMC CE check the status of the disk.

Re: pvcreate disk on SAN

Victor BERRIDGE — Thu, 01 Jul 2004 09:13:05 GMT

Let me guess...
You did a ioscan THEN insf -e ...

Only I dont remember seeing a vpath nor cfgvpath on HPUX, that makes me think you have some IBM software that does Virtual drive for dynamic load balancing, in such case its the vpath that you should use...

All the best
Victor

Re: pvcreate disk on SAN

Victor BERRIDGE — Thu, 01 Jul 2004 09:26:10 GMT

What do see when you do
ioscan -funC disk,
strings /etc/vpath.cfg

Knowing IBM I suppose ther is an lst???path or showvpath command, what does that give you?
Have you tried pvcreate -f /dev/rdsk/cxtxdx?

I believe like the others you have some problem on the SAN side or you may have some firmware upgrade to do

Good luck
Victor

Re: pvcreate disk on SAN

Todd McDaniel_1 — Thu, 01 Jul 2004 09:31:42 GMT

victor,

I think you misread his post... the type of actual disk is IBM not the array.

Or maybe I am misreading yours?

I'd bet dollars to donuts(always wanted to say that), he has a read only disk problem...

Re: pvcreate disk on SAN

Victor BERRIDGE — Thu, 01 Jul 2004 09:41:43 GMT

Well I dont know beacuse I havent seen one with HP connected nore do I work with one, but by guessing I would say the SAN is an IBM ESS (shark or whatever its called now) with IBM multipathing software...
Just thoughts...

All the best
Victor

Re: pvcreate disk on SAN

Victor BERRIDGE — Thu, 01 Jul 2004 10:03:08 GMT

I just wen to look on IBM and found "total storage SAN volume controller" ... and learnt that it also works with HDS9200 and some HP subsystems...
I join Dietmar here and believe this should be moved to storage where some competence should be looking and be please to answer...

All the best
Victor

Re: pvcreate disk on SAN

Kelly_49 — Thu, 01 Jul 2004 10:23:20 GMT

After some more trouble shooting, I found that it is probably within the SAN. (To those of you that thought this - congrats!!) Trouble shooting consisted of trying to get the disk set up on an AIX system, which we have most of, and where most of our knowledge base is... Thanks to all that contributed.

Re: pvcreate disk on SAN

Hein van den Heuvel — Thu, 01 Jul 2004 11:22:53 GMT

Be sure to run: ioscan -fnC disk
Vistor wrote:
"What do see when you do ioscan -funC disk"

I suggest to NOT use the -u (as this will just look in memory, not go out to the san).

fabio wrote:
"if you don't get "created successfully" what do you get?"

I had a similar situation as Kelly yesterday and you actually get nothing. It just returns without any message.

So Kelly has two indication that the wrong device file is being used: No message from pvcreate, no size on diskinfo.

Re: pvcreate disk on SAN

Kelly_49 — Fri, 02 Jul 2004 10:24:19 GMT

Apparently all of the LUNs that we were attempting to use had a persistent lock, or SCSI disk reservation bit, on them which prevented the disk from being added to another system.

The command that we used to determine this was "lquerypr". This tool gets installed when SDD is installed on AIX systems. It can be ran from any system with the problem.

The syntax to determine if a persistent lock exists on the disk is:

lquerypr -pv -h /dev/vpath?? <-- if this returns a 5-6 digit hex code then the disk has a persistent lock that needs to be cleared.

If the disk has a persistent lock then the command to clear the lock:

lquerypr -cvh /dev/vpath?? <-- this will clear the lock on the disk and allow it to be used again by other systems.

Strangely enough there is really no documentation about the command other than it gets installed w/SDD. And apparently not on HPUX. I checked.

Re: pvcreate disk on SAN

KapilRaj — Fri, 02 Jul 2004 10:34:02 GMT

if u have sdd installed you would be able to run lquerypr and remove the lock. Can't u remove the locak from an aix node after twin-tailing and zoning it to that node ?. I never tried this but u could give it a try.

2105 is ESS is'nt it ? r u using datapath as well ?

Kaps

Re: pvcreate disk on SAN

Gary L. Paveza, Jr. — Fri, 02 Jul 2004 13:13:31 GMT

Not sure if this will help, but if you are using a SAN and have some type of LUN Masking (where you make LUNs only available to some systems), then HPUX will show some of the disks with a size 0. I believe it has to do with the way the LUN IDs are assigned on the channel. For example, if we assign two disks (SCSI ID 4 and ID 5) but have SCSI ID 2 and 3 assigned to another system, this system shows 2 and 3 as size 0. It's kind of like a placeholder.

Re: pvcreate disk on SAN

Uwe Zessin — Fri, 02 Jul 2004 13:26:39 GMT

I remember when I helped my customer to get his HP-UX systems migrated to EVA we had the same problem (disk size 0). It was 'solved' by installing some patches. One of my colleagues later noted that HP-UX requires 'knowledege' about the disk model - else it will deny access by using size 0 as a placeholder.

Else you might have to install a special device driver that better understands the IBM box - Compaq, now HP, uses one in their multipathing software (Secure Path) for the EVA.

Re: pvcreate disk on SAN

Hein van den Heuvel — Fri, 02 Jul 2004 21:18:48 GMT

If the reservation is still bothering you, then you may be able to break through that with scsictl. From the man page:

-p pr_clear key device
The scsictl command with the -p pr_clear option can be
used to clear the persistent reservation from a device.
This command can not be used with any other options or
commands available for the scsictl command.

This command should be followed by two arguments: key
and device. key is a string of characters which was
used while setting persistent reservation. This key
can be in any of the following two formats:

(a) Text format: can contain any of alphanumeric
characters. In this format length of the key
should not exceed 8 characters.

(b) Hex format: preceded by 0x or 0X, can contain any
of hexadecimal digit. In this format length of the
string should not exceed 18 characters in total
(including 0x or 0X).

hth,
Hein.