topic Re: vgimport : not a character device in Operating System - HP-UX

vgimport : not a character device

Franky Leeuwerck_2 — Mon, 03 Oct 2005 05:22:06 GMT

Hi experts,

I've created a SAN-located volumegroup with filesystems on host A and want to remount these on host B.

I did an vgexport of the desactivated volumegroup :
vgexport -m myvg.map -s -p -v myvg

.. and continued on the other host :
vgimport -m myvg.map -s -v myvg

This is the output :
Beginning the import process on Volume Group "myvg".
vgimport: "/dev/myvg/group": not a character device.

Do I manually need to run this before doing the vgimport :
mkdir /dev/myvg
mknod /dev/myvg/group c 64 0x020000
or am I overlooking something ?

Regards,
Franky

Re: vgimport : not a character device

Pete Randall — Mon, 03 Oct 2005 05:23:57 GMT

Franky,

Yes, you need to create the directory and the device file for the group. Make sure the minor number in your mknod command is unique.

Pete

Re: vgimport : not a character device

RAC_1 — Mon, 03 Oct 2005 05:24:09 GMT

Yes. You need to run it.

mkdir /dev/myvg
mknod /dev/myvg/group c 64 0x020000

Re: vgimport : not a character device

Muthukumar_5 — Mon, 03 Oct 2005 05:25:36 GMT

Yes.

Check this steps 11 - 16:

http://docs.hp.com/en/B2355-90698/ch05s07.html

hth.

Re: vgimport : not a character device

melvyn burnard — Mon, 03 Oct 2005 05:27:00 GMT

Before you import a VG, you must have created a directory for the VG, and then the control file.
In your example
mkdir /dev/myvg
mknod /dev/myvg/group c 64 0x020000

Making sure the VG minor number is unique on the system you are doing the vgimport.

Re: vgimport : not a character device

Arunvijai_4 — Mon, 03 Oct 2005 05:28:04 GMT

Yes, You have to ,

# Scan your current system to identify all disks by their volume groups.

/usr/sbin/vgscan -v

# Create a directory for the volume group to which the new LVM disk will belong. For example, a new volume group might be called vg06.

mkdir /dev/vg06

# Check to make sure that you are creating a unique minor number for the new group file. Then create a character device special file for the new volume group's group file. The character major number for LVM is 64. In the minor number, n must be in the range between 0 and 9, because the maximum number of volume groups by default allowed on a system is ten. You can increase the number by changing the operating-system parameter maxvgs in /usr/conf/master.d/core-hpux or by using SAM.

ll /dev/*/group
mknod /dev/vg06/group c 64 0x0n0000

# Import the LVM disk to the current system, citing the block device special file name you noted when the system booted up and the mapfile you created when invoking vgexport at the beginning of the procedure. You can preview the effect of the import by using the -p option.

vgimport -pv -m mapfile /dev/vg06 block_device_special_file
vgimport -v -m mapfile /dev/vg06 block_device_special_file

The vgimport command adds the volume group name to the /etc/lvmtab file. It also adds the device special files associated with the volume group's logical volumes to the system.
# Activate the new volume group.

/usr/sbin/vgchange -a y /dev/vg06

# Mount the logical volumes to their new mount point. For further information on mounting and un-mounting, consult the Managing Systems and Workgroups manual.

mkdir /new_location
mount /dev/vg06/lvol1 /new_location

Re: vgimport : not a character device

James R. Ferguson — Mon, 03 Oct 2005 05:28:32 GMT

Hi Franky:

Yes, the group device file must be created. Make sure, too, that your device number, in this case, "02" is unique. Remember too, that the value is expressed in hexadecimal.

Regards!

...JRF...

Re: vgimport : not a character device

Franky Leeuwerck_2 — Mon, 03 Oct 2005 08:35:31 GMT

Thanks for your replies.

After creating the vg device file ( mkdir, mknod ), I tried again but received this error :

(host B)# vgimport -m myvg.map -s -v myvg
Beginning the import process on Volume Group "myvg".
Couldn't access the list of physical volumes for volume group "/dev/myvg".

Any suggestions ?

Franky

Re: vgimport : not a character device

melvyn burnard — Mon, 03 Oct 2005 08:43:16 GMT

This suggests it cannot see any of the discs that are/were in the vg on th eother host.
Are you sure you can "see" them from this host?

Re: vgimport : not a character device

Howard Marshall — Mon, 03 Oct 2005 08:49:37 GMT

If the command you typed is the command you entered there is something missing.

Two choices, you can create a file with a list of physical volumes using the -e switch or you can just add the list to the end of the command.

Sense the volume group doesn't exist on this machine, the system has no record and doesn't know which physical volumes to import from otherwise.

H

Re: vgimport : not a character device

Franky Leeuwerck_2 — Mon, 03 Oct 2005 08:52:42 GMT

Melwin,

This the volumegroup that was created on host A :
mkdir /dev/vg03P
mknod /dev/vg03P/group c 64 0x030000
pvcreate -f /dev/rdsk/c15t0d7
pvcreate -f /dev/rdsk/c15t1d0
vgcreate vg03P /dev/dsk/c15t0d7 /dev/dsk/c15t1d0

When I do an ioscan on host B, I do not see any devices starting with c15t.. . Is that the problem ?

Franky

Re: vgimport : not a character device

melvyn burnard — Mon, 03 Oct 2005 08:58:29 GMT

Well usually when "sharing " across nodes, you should keep the VG minor numbers the same.
As for the c15txdy numbers, they do NOT have to be the same as it depends on the interface instance you are using.
This is why you can use the vgimport -s -m mapfile option. It forces the vgimport command to go out and scan ALL of the interfaces and disks the system can see, and tries to match up the VGID/PVID on any disc to what is in the map file.

You say these are in a SAN environment, are you sure these discs have been made visible to the 2nd host?
Try doing an ioscan -f, then an insf -e and see if new discs appear on node B

Re: vgimport : not a character device

Franky Leeuwerck_2 — Mon, 03 Oct 2005 09:08:41 GMT

Melwyn,

Ran your commands but still the same :
(host B)# vgimport -m vg03P.map -s -v vg03P
Beginning the import process on Volume Group "vg03P".
Couldn't access the list of physical volumes for volume group "/dev/vg03P".
(host B)#

Franky

Re: vgimport : not a character device

Gavin Clarke — Mon, 03 Oct 2005 09:12:52 GMT

Franky, what sort of SAN have you got?

I think it may be that the LUNs created need to be presented to Host B (if EVA). Or the secure manager table needs to be configured (if VA).

Re: vgimport : not a character device

melvyn burnard — Mon, 03 Oct 2005 09:14:30 GMT

It looks as if the discs/LUN's have not been presented to node B. You need to fix this first before you can proceed.

Re: vgimport : not a character device

Franky Leeuwerck_2 — Mon, 03 Oct 2005 09:22:52 GMT

The SAN is an EVA.

For now, I'll close the thread.
Though, I don't have solution for now, I now at least where the problem is located now. I'll try to get in touch with the local HP Support team for fixing the setup.

Thanks and regards,
Franky

Re: vgimport : not a character device

Franky Leeuwerck_2 — Mon, 03 Oct 2005 09:26:42 GMT

Thread closed.