Installing 11.0

[james gould]

Will be installing 11.0 and will be doing the
following before starting the install on the
server as suggested by HP to preserver other
volumes and filesystem information.

Unmount all the file systems in vgxx umount /mount_point.
Deactivate the volume group vgchange -a n /dev/vgxx
create a map file for vgxx_mapfile cd /; touch vgxx_mapfile
vgexport -m vgxx_mapfile -sv /dev/vgxx Export the volume group

My question is can a map file be created in
preview mode and work just as well without
having to umount the filesystems and performing a deactivation on the volume groups?

Thanks

[Sridhar Bhaskarla]

Hi James,

Yes. There will be no difference in the contents of the map file with or without 'preview' option.

-Sri

[Martin Johnson]

The same map file will be created in preview mode.

Make sure you save the map files where you can get at after the install (i.e. not on vg00). backup to tape, ftp, etc.


HTH
Marty

[A. Clay Stephenson]

Yes. The preview mode will do this quite well.

You should be aware that it is possible that some of your controller instances may change between OS loads especially if cards have been added/moved/removed since the current OS was installed. What was c1 may now be c3, for example. I woulds make sure that I had hardcopies of bdf, ioscan -fn, /etc/fstab, and a strings /etc/lvmtab.

[James R. Ferguson]

Hi James:

have a look at the '-s' option of 'vgexport'. This allows you do create map files without actually exporting the volume group.

When you get to 11.0, 'vgimport' allows you to specify the device pv_paths on the command line or in a file ('-f infile'). This is quite useful coupled with the 11.x '-f outfile' companion option of 11.x 'vgexport'. You can collect the current pv_path information and edit it as/if necessary.

Unfortunately, you do not have the '-f' feature in 10.20, but after your upgrade you could immediately use it in the 'vgimport' processing.

Regards!

...JRF...

[Nick Wickens]

Hi

As others have already said the preview option works fine for creating a map file but I would stress the last point above to have an ioscan and would also suggest you print the output of a "vgdisplay -v" command for all of your volumes. This will give you a list off all of the disks in each volume (put the output through grep and just get the disk ids as thats all you really want). The reason for this is that it is possible to perform a vgimport without a map file provided you can sepcify all of the disks that were in the original volume group. I did'nt realise this until a few months ago and it saved me several hours of work when a consultant knackered a system during a rebuild.

[James R. Ferguson]

Hi (again) James:

Nick makes an important point. The mapfiles are really convienent insurance. 'vgimport' creates logical volume devices files under the vg_name directory using the naming convention given in a mapfile. In the absence of the mapfile, the default naming convention used by the 'lvcreate' applies (which is what one generally (?) uses anyway.

Regards!

...JRF...

[Everett R. Stroman]

Hello James,

Looks like you have recieved some great advice, I always make map files while the vg is still active. Like advised I make a important files dir in /var/tmp. I make the map file like so:
vgexport -p -v -s -m /var/tmp/important/vg01.mapfile /dev/vg01

Unlike many Unix tools, the options cannot be combined (-pvsm).
Note that you my see a massages saying that Volume group "/dev/vgXX" is still active. Ignore it as the mapfile is created anyway, each mapfile should look something like this:

VG serial number 1234567890
1 lvol1
2 lvol2
3 lvol3
...
and so on. vgimport (and SAM) understands this file with or without the serial number(the serial number is added by using the -s option). The serial number ensures that the right disk(s) will be assigned to the selected volume group.

Hope this helps, and good luck

Everett