fix PP placement int a mirrored VG with 3 disks 1

[trifo]

Hi!

I have an AIX node with 3 disks in the rootvg (same size). I would need to store data mirrored, so that losing 1 disk can be survived. Also for some reason, I need to eat up ALL of the space available. (waiting for new disk capacity with eager).

The issue is that the present volumes had been created simply mirrored, thus not using the 3 disks well distributed.

Now I know that the logical volumes should have been created like

mklv -y volumename -e x -s y .....

so that instructing mklv to use the maximum number of PV-s in the operation, disabling superstrict PP mirror placement.

My question is that is there a method to reorganize PP placement without recreating the logical volumes?

I tried to change LV attributes using chdev (referring -e x anf -s y ) and then running reorgvg, but it did not do the job for me. Do you have any better idea?

--Trifo

 

[MoreFeo]

Not sure if I've understood what you need, but maybe migratepv will do what you need.

migratepv -l LVName source_hdisk target_hdisk

Take a look at

http://publib.boulder.ibm.com/infoc...=/com.ibm.aix.cmds/doc/aixcmds3/migratepv.htm

HTH

 

[trifo]

Well, I have been using migratepv several times before but then I only had pairs of disks to be replaced.

Now I have 3 PV-s and a quite big LV with a misconfigured mirror. Something like this:

     hdisk1       hdisk2       hdisk3
LP1: PP1(mirror1) PP1(mirror2) -
LP2: PP2(mirror1) PP2(mirror2) -
LP3: PP3(mirror1) PP3(mirror2) -
...

But I want it shomehow like this:

     hdisk1       hdisk2       hdisk3
LP1: PP1(mirror1) PP1(mirror2) -
LP2: -            PP2(mirror1) PP2(mirror2)
LP3: PP3(mirror1) -            PP3(mirror2)
...

so that every LP is mirrored in 2 copies, and every PP of an LV mirror copy is evenly distributed among the 3 disks.

Can migratepv do this?

--Trifo

 

[p5wizard]

migratelp I'd think, but that is PPcopy per PPcopy, so it will need some scripting...

HTH,

p5wizard

 

[trifo]

Thanks! I always get surprised on how handy commands AIX has. The scripring knowledge is available, so I will be able to do the work now.

Thanks again

--Trifo