Aix : Grow / expand your rootvg on the fly (from 6.1 TL 4)

Increase rootvg dynamically

If your rootvg “disk” is actually virtual, such as a SAN LUN or a logical volume on the VIO server, then it usually can be expanded on the SAN (or using extendlv on the VIOS) and then recognised on the AIX LPAR using the -g flag of the chvg command:

chvg -g rootvg

Note: this is supported for rootvg and concurrent vgs from AIX 6.1 TL 4. See IBM technote IZ80021 http://bit.ly/cmHjmy

Resizing the rootvg disk

I tried to increase rootvg on an LPAR running AIX 5.3 TL 11 and hit the following error:

aix53_lpar # chvg -g rootvg

0516-1380 chvg: Re-sizing of the disks is not supported for the rootvg.

0516-732 chvg: Unable to change volume group rootvg.

Looks like the volume group needed to be varied off and varied on again. For rootvg, that means a reboot.

No reboot on AIX 6.1

In AIX 6.1 (from TL 4 – use oslevel -s to check your AIX level), you can increase rootvg on the fly.

aix61_lpar:/# chvg -g rootvg

0516-1164 chvg: Volume group rootvg changed.  With given characteristics rootvg can include up to 16 physical volumes with 2032 physical partitions each.

Example :

bash-3.2# lsvg rootvg
VOLUME GROUP:       rootvg                   VG IDENTIFIER:  00f8c83f00004c00000001436bebe1dd
VG STATE:           active                   PP SIZE:        256 megabyte(s)
VG PERMISSION:      read/write               TOTAL PPs:      119 (30464 megabytes)
MAX LVs:            256                      FREE PPs:       16 (4096 megabytes)
LVs:                12                       USED PPs:       103 (26368 megabytes)
OPEN LVs:           11                       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): 512 kilobyte(s)          AUTO SYNC:      no
HOT SPARE:          no                       BB POLICY:      relocatable
PV RESTRICTION:     none                     INFINITE RETRY: no
bash-3.2# chvg -g rootvg
bash-3.2# lsvg rootvg
VOLUME GROUP:       rootvg                   VG IDENTIFIER:  00f8c83f00004c00000001436bebe1dd
VG STATE:           active                   PP SIZE:        256 megabyte(s)
VG PERMISSION:      read/write               TOTAL PPs:      199 (50944 megabytes)
MAX LVs:            256                      FREE PPs:       96 (24576 megabytes)
LVs:                12                       USED PPs:       103 (26368 megabytes)
OPEN LVs:           11                       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): 512 kilobyte(s)          AUTO SYNC:      no
HOT SPARE:          no                       BB POLICY:      non-relocatable
PV RESTRICTION:     none                     INFINITE RETRY: no
bash-3.2# oslevel -s
7100-02-02-1316
bash-3.2#