Mirrioring problem of LV in Cluster aware VG.

[SR_2006]

I am not able to mirror lv. lvextend -m 1 because strict allocation policy. my vg contains 2 pv . Out of 2 pv one pv is having sufficient PE while other pv having 0 pE.this vg is under cluster enviorment.
Now my plan is

1)create LUN & do vgextend
2)down the package
3)do vgexport on 1 st node & vgimport it on second node (After vgexport of that vg on second node)
4)start the package

Now for mirroring LV my vg contains 3 PV.(out of which 2 PV having sufficient PE while other having 0 PE.).
now my plan is
lvextend -m 1 or using only lvextend -m 1 it will automatically take that new device path.
pl. confirm whether my procedure is ok or not.

thanks in advance.

[Mancboy · Accepted solution]

your plan looks reasonable, ensure you specify the destination device for the mirror otherwise it can go anywhere.

One thing I would look at, is how your data is organised. Is it all bunched up on the 1st PV, because you've always mirrored without specifying the 2nd PV?

I would run a lvdisplay -v on the LVs that are already mirrored and see which ones are mirrored onto the same disc.

Then I'd remove the mirrored copies and reapply them (specifying PV2).
Also look at "pvmove"ing any LVs that are clogging up PV1 and put them on PV2.
It should help to spread the load between the two discs.

[Steven E. Protter]

Shalom,

Procedure looks good.

vgdisplay -v vgname

Use a real vg name.

You may need to do a pvdisplay -v on the phyiscal volumes to get a clear picture. You may also need to do a lvdisplay -v lv_name to see where things are laid out.

It is important to understand that mirroring does you no good if a logical volume is mirrored on the same disk. It is ideal to make a mirror copy on another disk controller to provide full redundancy.

Note however, if you have LUN's assigned to your machine there is little need to do anything. Talk to the person that assigned the LUN and see, this LUN may already be mirrored on the disk array or perhaps it can be set to raid 1 by the LUN/SAN/Array admin.

SEP

[SR_2006]

thanks for ur information.