Enlarging the size of a striped LV

Since there were not enough free PPs available within the VG to extend our fast growing LV we had to increase disk space and extend this LV, but this was a little different from the usual manner because of this LV was a striped one. At first we thought we had to rebuild the entire LV to expand to the new capacity, but… since AIX 5L version 5.3 it is possible to enlarge the size of striped LVs online thanks to the concept of striped columns for LVs. The only thing is that you can raise the upper bound with a multiple of the stripe width. Our SAN team was so happy to supply the necessary LUNs.

This is what it looked like:

# lslv fslv17
LOGICAL VOLUME:     fslv17                 VOLUME GROUP:   oradatavg3
LV IDENTIFIER:      00c1e99000004c000000011b8d014031.2 PERMISSION:     read/write
VG STATE:           active/complete        LV STATE:       opened/syncd
TYPE:               jfs2                   WRITE VERIFY:   off
MAX LPs:            6144                   PP SIZE:        64 megabyte(s)
COPIES:             1                      SCHED POLICY:   striped
LPs:                5580                   PPs:            5580
STALE PPs:          0                      BB POLICY:      relocatable
INTER-POLICY:       maximum                RELOCATABLE:    no
INTRA-POLICY:       middle                 UPPER BOUND:    6
MOUNT POINT:        /oracle/data/P30       LABEL:          /mnt
MIRROR WRITE CONSISTENCY: on/ACTIVE
EACH LP COPY ON A SEPARATE PV ?: yes (superstrict)
Serialize IO ?:     NO
STRIPE WIDTH:       6
STRIPE SIZE:        128K
#

Use the -u option to extend the upper bound. This can only be a multiple of the stripe width, which is 12 in my case.

# chlv -u 12 fslv17
# lslv fslv17
LOGICAL VOLUME:     fslv17                 VOLUME GROUP:   oradatavg3
LV IDENTIFIER:      00c1e99000004c000000011b8d014031.2 PERMISSION:     read/write
VG STATE:           active/complete        LV STATE:       opened/syncd
TYPE:               jfs2                   WRITE VERIFY:   off
MAX LPs:            5120                   PP SIZE:        64 megabyte(s)
COPIES:             1                      SCHED POLICY:   striped
LPs:                4776                   PPs:            4776
STALE PPs:          0                      BB POLICY:      relocatable
INTER-POLICY:       maximum                RELOCATABLE:    no
INTRA-POLICY:       middle                 UPPER BOUND:    12
MOUNT POINT:        /oracle/data/P30       LABEL:          /mnt
MIRROR WRITE CONSISTENCY: on/ACTIVE
EACH LP COPY ON A SEPARATE PV ?: yes (superstrict)
Serialize IO ?:     NO
STRIPE WIDTH:       6
STRIPE SIZE:        128K
#

After that we had to extend the Maximum LPs for this LV.

# chfs -a size=+40G /oracle/data/SID
0516-787 extendlv: Maximum allocation for logical volume fslv17
is 5120.
# chlv -x 6144 fslv17
# chfs -a size=+40G /oracle/data/SID
Filesystem size changed to 731381760
#

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