topic Re: Extending a mirrored filesystem in Operating System - HP-UX

Extending a mirrored filesystem

Stephen Young_1 — Mon, 21 May 2001 11:20:01 GMT

Can someone tell me the syntax for extending
a mirrored lv when there are more than two pv's
in the volume group.

Cheers in advance

Re: Extending a mirrored filesystem

James R. Ferguson — Mon, 21 May 2001 11:27:20 GMT

Hi Stephen:

To mirror onto a specific disk use this syntax:

# lvextend -m 1 /dev/vgXX/lvolX /dev/dsk/cXtYdZ

...JRF...

Re: Extending a mirrored filesystem

Vincent Stedema — Mon, 21 May 2001 11:41:57 GMT

Hi Stephen,

lvextend the primary lvol to the disk you want the newly allocated PE's to reside on. Use lvdisplay to determine on which disk in your vg the mirrored PE's are located and then use pvmove to move the mirrored data to the disk you want to use as the secondary disk.

Hope this helps.

Vincent

Re: Extending a mirrored filesystem

Vincenzo Restuccia — Mon, 21 May 2001 11:42:10 GMT

#lvextend -m 1 /dev/vg00/lvolx /dev/dsk/cxtxd0
and see http://docs.hp.com/hpux/onlinedocs/B2355-90672/B2355-90672.html

Re: Extending a mirrored filesystem

Carsten Krege — Mon, 21 May 2001 11:44:22 GMT

James gave you the syntax of how to create a mirror copy of an unmirrored lvol.

The following gives you the syntax of increasing the size of an mirrored lvol.

lvextend -l /dev/vgXX/lovlX /dev/dsk/ /dev/dsk/

This will extend the size of the lvol to newsize (numbers of physical extents), taking the extents from disk1 and disk2. With the allocation policy set to "strict" (default) the two mirror copies of the disk will always be on different disks.

You might be interested in using physical volume groups. A full descriptiuon of this feature, together with examples, is in the manpage lvmpvg(4). Once setup, it will always take care that the allocation of extents is done properly.

Carsten