Originally posted by: navee7777

Hi,
I am new to this AIX environment.
I have a single PV "hdisk0" size about 300 gb is entairly occupied by "rootvg". I tried to create new VG on the same PV but failed.
1) Can I reduce the size of existing volume group "rootvg" ....????
2) Can I create multiple VG on the same PV...????

Please guide me with the proper commands..

Thanks in advance... :)
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Originally posted by: navee7777

some information
AIX 6.1

-bash-3.2# mkvg -y sqmvg -s 4 hdisk0
0516-1398 mkvg: The physical volume hdisk0, appears to belong to
another volume group. Use the force option to add this physical volume
to a volume group.
0516-862 mkvg: Unable to create volume group.
-bash-3.2# mkvg -y -f sqmvg hdisk0
0516-306 mkvg: Unable to find physical volume sqmvg in the Device
Configuration Database.
0516-862 mkvg: Unable to create volume group.
-bash-3.2# lsvg rootvg
VOLUME GROUP: rootvg VG IDENTIFIER: 000f14da0000d400000001364562c0ae
VG STATE: active PP SIZE: 512 megabyte(s)
VG PERMISSION: read/write TOTAL PPs: 599 (306688 megabytes)
MAX LVs: 256 FREE PPs: 46 (23552 megabytes)
LVs: 23 USED PPs: 553 (283136 megabytes)
OPEN LVs: 19 QUORUM: 2 (Enabled)
TOTAL PVs: 1 VG DESCRIPTORS: 2
STALE PVs: 0 STALE PPs: 0
ACTIVE PVs: 1 AUTO ON: yes
MAX PPs per VG: 32512
MAX PPs per PV: 1016 MAX PVs: 32
LTG size (Dynamic): 256 kilobyte(s) AUTO SYNC: no
HOT SPARE: no BB POLICY: relocatable
PV RESTRICTION: none
-bash-3.2#
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Originally posted by: romeo_ninov

1. Not in you case
2. No, if you read the manuals for LVM on AIX you will see that only entire PV can be in VG. No partitioning, slicing, etc
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Originally posted by: SystemAdmin

hi,

You can't create a second VG on the same PV
it's true with AIX, Linux, HP-UX
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Originally posted by: romeo_ninov

biblio93, this is wrong, in Linux you can use as PV entire disk or just one partition from the disk. So if you want you can create list of partitions and assign them to different VGs
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Originally posted by: SystemAdmin

Hi,

You cannot create multiple VG in one PV. But you can make multiple LVs in a VG.

Regards
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