Question
Can I change the MAX PPs per VG value on an active Volume Group?

Cause
Need to add additional disks/luns to the VG which will require an increase of the Volume Groups MAX PPs per VG attribute.

Answer
The MAX PPs per VG value can be increased dynamically against an active (imported/varied on) Volume Group. The new value must be greater than the existing value. Once increased, the value cannot be decreased without removing and recreating the VG.
Using chvg on the command line…
eg, to change MAX PPs per VG to

labserver:/ # /usr/sbin/chvg -P 256

(or)

labserver:/ # smitty chvg
Enter the VG name and change the following entry to the desired value…
Max PPs per VG in units of 1024 32

Acceptable values for MAX PPs per VG are 32, 64,128, 256, 512, 768, 1024, 2048

32 = MAX PPs per VG: 32768
64 = MAX PPs per VG: 65536
128 = MAX PPs per VG: 131072
256 = MAX PPs per VG: 262144
512 = MAX PPs per VG: 524288
768 = MAX PPs per VG: 786432
1024 = MAX PPs per VG: 1048576
2048 = MAX PPs per VG: 2097152