Questions about PVGs

[R.O.]

Hi,

How works the pvgs? Have they the same function as stripping? I have seen if I export a Vg configuration and import it in other node, the file "/etc/lvmpvg" is not automatically updated, and I have to do it by hand (this is very boring if the disks have different device files in both nodes). What could happen if the package migrates and the file lvmpvg is not updated?

Regards,

[James R. Ferguson · Accepted solution]

Hi:

First, have a look at the manpages, in particular the mapages for 'lvmpvg(4)' and 'lvcreate(1M)':

http://docs.hp.com/en/B2355-60127/lvmpvg.4.html

http://docs.hp.com/en/B2355-60127/lvcreate.1M.html

The '/etc/lvmpvg' file is most useful for creating extent-based stripes (which differ from LVM stripes).

The '/etc/lvmpvg' file is removed if/when you do a 'vgexport' of a volume group. It is *not* used during 'vgimport', nor is it created during that process.

A 'vgexport' and 'vgimport' can specify device path information using a file associated with the '-f' option as noted in the respective manpages for 'vgexport' and 'vgimport'. This allows the collection and specification of physical device paths. The file created by an export can be editted before it is used for import. This is common when moving a volume group with multiple disk paths to a different server, for instance.

Another use of the 'outfile/infile' associated with the 'vgexport/vgimport' '-f' switch is to make sure that primary and alternate path assignements and balance are retrainted trhough the export/import process.

Regards!

...JRF...