AIX

Does anyone know how to set PP (Physical Partition) size on rootvg when installing AIX OS from scratch (via CD or NIM installation)?

you can do it by smit(System Managment Interface Tool)
System Storage Management (Physical & Logical Storage)--> Logical Volume Manager
--> Volume Groups-->Add a Volume Group-->Add an Original Volume Group
then choose the PP there..

For the rootvg, you cannot change it once your OS is installed, so using vidyadhar85's idea I don't think will work. One way you can set during a NIM restore is by specifying a image.data file that has the PPSIZE set to what you want it to be. Here is the part of an image.data file that refers to the rootvg attributes. The PPSIZE here is set to 64MB:

Code:

vg_data:
        VGNAME= rootvg
        PPSIZE= 64
        VARYON= yes
        VG_SOURCE_DISK_LIST= hdisk0
        QUORUM= 2
        ENH_CONC_CAPABLE= no
        CONC_AUTO= no
        BIGVG= no
        TFACTOR= 1

Another thing you could try, I'm not sure if it would work or not, is to create a mksysb backup to your NIM server, copy over the image.data and bosinst.data files to you NIM server also. Modify the copied image.data file and set the PP size to what you want the rootvg PP size to be. You will also have to update the "PP_SIZE", "PP", and "LPs" variables for each filesystem also in the image.data file in accordance with the change in the rootvg PP size. Setup all three items as NIM resources. Restore the mksysb and specify the image.data and bosinst.data NIM resources and when NIM goes to create the rootvg, he "should" create it with the PP size specified in the image.data file.

I did something similar to this to change our rootvg filesystems from JFS to JFS2. IBM said they didn't "officially" support what I did, but they did say it would work.

Yes, I ended up making mksysb backup to tape after changing the PP size and image.data file, then restored it back from the tape.
But, my original question was: is there a way to set the PP size during the initial install of OS?
Thanks everyone for your input

Afaik no.
If it helps your problem, you can just try to change the PP factor with

Code:

chvg -t 2 rootvg

after the installation, if you have disks that are somewhat too large for your PP size.
Or try to change it to Big LV or a ScalableVG. Never tried that with rootvg though, but there are some points in "man chvg" for that, if you decide to do it.

Thanks everyone! for your input.