QUORUM in aix

what is quorom in aix ?


During my AIX learning day i always wondered about what is quorom and how it affect volume group on AIX ? But after doing google i found answer like below.

Here is the answer :

Number of disk must be present in volume group to successfully vary on volume group in AIX.

"51% is mandatory vgda."


for example, XYZ volume group having 6 disk so mandatory disk for 51% VGDA is 4.

if disk in volume group is 10 then mandatory disk for 51% VGDA is 6.

Its simple


51% VGDA=Number of disk in Volume group/2 +1


so what happen if that mandatory percentage (51%) not available ?

rootvg quorom always kept disabled.

QUORUM:         1 (Disabled)

Reason behind this is when AIX OS boot and at the time of boot if rootvg having 2 disk and 1 disk from rootvg crashed then OS will never came up,because it not satisfies 51% VGDA rule.so its always good idea to keep mirrored rootvg quorom disabled.



will update new idea and thought on AIX

Thanks !!