topic Re: how to import a cloned LUN in Operating System - HP-UX

how to import a cloned LUN

tom quach_1 — Wed, 02 Apr 2008 04:09:41 GMT

Dear,

in EVA3000, i created a LUN1 and presented to server1 (HPUX 11.23), created vg01 and have file system on it.
clone LUN1 to LUN2 and presented it to server2 (HPUX 11.23).
Question: is there any procedure to import LUN2 to server2 with vg01

Regards,
Tom

Re: how to import a cloned LUN

Sandy Chen — Wed, 02 Apr 2008 06:15:44 GMT

Hi Tom,

How do you clone LUN1 to LUN2?

You could try this steps to export a mapfile of vg01 on the server1 to server 2:

on server1:
# vgexport -s -p -v -m vg01.mapfile

copy the file vg01.mapfile to server2, and then on the server2 run this:

# mkdir /dev/vg01
# mknod /dev/vg01 c 64 0x010000
# vgimport -s -v -m vg01.mapfile vg01

Regards,
Sandy

Re: how to import a cloned LUN

tom quach_1 — Wed, 02 Apr 2008 06:49:14 GMT

Thanks Sandy,

i clone it from EVA3000
when import the device file will be different.
what you going to do about it?

Thanks-Tom

Re: how to import a cloned LUN

Sandy Chen — Wed, 02 Apr 2008 06:59:27 GMT

Hi,

I assume you are using CA or BCV. As long as the LVM header didn't change, the device changes wouldn't be an issue.

Regards,
Sandy

Re: how to import a cloned LUN

Eric SAUBIGNAC — Wed, 02 Apr 2008 08:20:19 GMT

Bonjour Tom,

In a vgimport operation the fact that the device file is not the same as original one has no side effect : the -s option of the vgimport will track the VGID written in the mapfile on all visible LUNs.

But due to the fact that you have cloned the VG, it is a better pratice to change this VGID. For example you could have a cluster in the future and it does not support different VG having same VGID.

If you change VGID, the vgimport with -s option will not work. You should work as follow on server2, assuming your cloned LUN is seen as cXtYdZ :

# vgchgid /dev/rdsk/cXtYdZ
# mkdir /dev/vg01
# mknod /dev/vg01 c 64 0x010000
# vgimport -v -m vg01.mapfile vg01 /dev/dsk/cXtYdZ
# vgchange -a y vg01

Note : if you have several LUNs in one VG, vgchgid and vgimport commands must be executed on all LUNs in a single pass. For exemple :

# vgchgid /dev/rdsk/cXtYdZ /dev/rdsk/cAtBdC ...
# vgimport -v -m vg01.mapfile vg01 /dev/dsk/cXtYdZ /dev/dsk/cAtBdC ...

Regards

Eric

Re: how to import a cloned LUN

Torsten. — Wed, 02 Apr 2008 12:02:10 GMT

With all of the above you should be successful.

my 2 cents:

"vg01" is just a name while you import this VG. You can even call it myfavouritevg or whatever, but it is a good practice to call them vg01 vg02 and so on and create a corresponding device number for it, e.g.

# mknod /dev/vg01 c 64 0x010000
# mknod /dev/vg02 c 64 0x020000
# mknod /dev/vg03 c 64 0x030000