topic Re: Problem importing volume group in Operating System - HP-UX

Problem importing volume group

Tom Frencel — Fri, 03 May 2002 17:31:37 GMT

Hello,

I am having a problem importing a volume group. Let me give you an overview of our environment first. The host computer on which the import is attempted is running HP-UX 11.00.
We have an EMC Symmetrix environment set up. We are trying to import a volume group from the primary host onto the secondary host. The import will be attempted from BCVs after the split has taken place. Here is the information about the volume group as displayed by vginfo on the primary host:

--- Volume groups ---
VG Name /dev/313nmesvg1
VG Write Access read/write
VG Status available
Max LV 255
Cur LV 1
Open LV 1
Max PV 16
Cur PV 2
Act PV 2
Max PE per PV 1079
VGDA 4
PE Size (Mbytes) 4
Total PE 2156
Alloc PE 250
Free PE 1906
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0

--- Logical volumes ---
LV Name /dev/313nmesvg1/nmesvg1_vol1
LV Status available/syncd
LV Size (Mbytes) 500
Current LE 125
Allocated PE 250
Used PV 2

--- Physical volumes ---
PV Name /dev/dsk/c4t9d0
PV Status available
Total PE 1078
Free PE 953

PV Name /dev/dsk/c4t9d1
PV Status available
Total PE 1078
Free PE 953

What we have done is created a logical mirrored volume in our volume group 313nmesvg1. That's the reason why only one logical volume gets displayed. There are two logical volumes that were created, however, one is simply a mirror.

Now we perform the import steps on the secondary host after the BCVs has been split:

We go through the standard procedure of executing:

1) vgchgid /dev/dsk/c10t3d6 /dev/dsk/c10t3d7

2) mkdir /dev/313nmesvg1
3) mknod .....

THE PROBLEM OCCURS IN STEP 4

4) vgimport -m /bigspace/rbrown/map -v 313nmesvg1 /dev/dsk/c10t3d6 /dev/dsk/c10t3d7

"Beginning the import process on Volume Group "313nmesvg1".
vgimport: Unable to read the physical volume."

This is the first time we have seen this problem and it only occurs on one volume group - 313nmesvg1, which contains the mirrored logical volume: 1 logical + 1 mirror.

We are puzzled by this error message as we are following the standard procedure of importing a volume group from BCVs and we DO make sure that the BCVs are split and readable.

What do you think the problem may be here???

Any help is greatly appreciated.

Many thanks in advance.

Re: Problem importing volume group

Sandip Ghosh — Fri, 03 May 2002 18:10:07 GMT

Why don't you try with -s option. Then it could remember the VGDA for the disk.

Sandip

Re: Problem importing volume group

Helen French — Fri, 03 May 2002 18:13:27 GMT

Hi Tom:

Check and try the options given in this document (TKB# KBRC00009160):

http://us-support.external.hp.com/cki/bin/doc.pl/sid=e50bdc5009b431bfbb/screen=ckiDisplayDocument?docId=200000059927129

HTH,
Shiju

Re: Problem importing volume group

MANOJ SRIVASTAVA — Fri, 03 May 2002 18:19:36 GMT

Hi Tom

Try this:
vgimport /dev/313nmesvg1 /dev/dsk/c10t3d6 /dev/dsk/c10t3d7

w/o the map file it should be able to do it properly if the vgchgid command is run fine. Also there may be a problem if the BCV device is also a part of some otehr vg.

Manoj Srivastava

Re: Problem importing volume group

Jordan Bean — Mon, 06 May 2002 16:51:47 GMT

Out of curiosity, why are you using HP LVM mirroring instead of Symmetrix hypervolume mirroring?

When you split the BCVs, do you verify that the LVM mirrors are sync'd? I don't know if stale extents cause vgimport to complain. Inquire with `lvdisplay -v` and enforce with vgsync. Are you also deactivating the original vg before splitting?

As long as the BCVs are presented to another host, then vgchgid is not necessary. It is required, however, when BCVs are presented to the same host. If you refrain from using vgchgid, then the vg only needs to be imported once. It would be sufficient to use vgchange between TimeFinder splits.

Re: Problem importing volume group

Rita C Workman — Mon, 06 May 2002 17:22:19 GMT

My exports tend to read like this:

vgexport -pvs -m /dirpath/mapfile.map /dev/vgname

My import tend to read like this:

vgimport -vs -m /dirpath/mapfile.map /dev/vgname

Since both systems have access to all the disks..I don't have to add the /dev/dsk..handles ok.
So far, it has worked OK on my EMC Symmetrix.

Just a thought,
Rita

Re: Problem importing volume group

Roger Baptiste — Mon, 06 May 2002 20:42:07 GMT

hi tom,

If you are having two server and the BCV is being accessed by the second server, there is no need to run the vgchgid command!!

The simplest way to export/import the maps would be to run:

vgexport -p -v -s -m vg.map vg
on the primary

Then, on the BCV system, run
vgimport -v -m vg.map vg

If you are using filesystems in the VG, you would also need to move the fstab entries for those filesytems and mount them.

HTH
raj

Re: Problem importing volume group

Pashupati Kumar — Thu, 27 Jun 2002 22:49:51 GMT

Hi,
I don't have a solution to the problem, but we are facing similar problem. Though, we are not using mirror volume, but we have hp mirror disk installed on the system. Problem seems to be related to vgchgid. If we don't do this, then import works fine. We need to do vgchgid because we might want to import the vg on the same host and also with different vg name.

thanks
pash