Re: mirror striped lvol

 
Jiri D
Advisor

mirror striped lvol

Hi,

I have a striped lvol on 3 pv. I need move this lvol on another 3 disk with the same size. Can I mirror this lvol via lvextend -m 1 new_disks. When mirror will be competed - lvreduce -m 0 old_disks. Will I have a striped lvol?

Jirid
4 REPLIES 4
Elmar P. Kolkman
Honored Contributor

Re: mirror striped lvol

This should work, yes.

You can check with lvdisplay -v after adding the mirroring. LE's should be linked to PE's the same way on the mirror as on the original.
Every problem has at least one solution. Only some solutions are harder to find.
Bernhard Mueller
Honored Contributor

Re: mirror striped lvol

Jirid,

you cannot LVM mirror lvols which are LVM striped - using -i -I options in lvcreate. You can only mirror lvols that use "distributed extents" (lvcreate -D y).

But you can use the pvmove command to move extents of an lvol from one disk to another in the same vg.

Regards,
Bernhard
Jeff Schussele
Honored Contributor

Re: mirror striped lvol

Hi Jirid,

Sorry, no you cannot mirror an LV with "normal" striping that was created with the -i & -I parms of the lvcreate cpmmand.

The only striping that can be mirrored are extent-based stripes created by the -D parm of vgcreate. This is normally an ineffective method of striping as the smallest stripe size is 1 MB.

Rgds,
Jeff
PERSEVERANCE -- Remember, whatever does not kill you only makes you stronger!
Jeff Schussele
Honored Contributor

Re: mirror striped lvol

Sorry - the distributed allocation parm, -D, is an lvcreate parm not a vgcreate switch.

Rgds,
Jeff
PERSEVERANCE -- Remember, whatever does not kill you only makes you stronger!