How to extend the size of Logical Volume (LV) in HP-UX

Sometimes we need to extend the size of a logical volume to increase the free space when running out of space. One of my servers has logical volume /dev/vg00/lvol5 mounted on /opt which becomes 76% full so I have to increase the size of the Logical Volume (LV) /dev/vg00/lvol5. I have to extend it from 16 GB to 18 GB online without any downtime for my server.

# bdf /opt
Filesystem          kbytes    used   avail %used Mounted on
/dev/vg00/lvol5    16777216 12807008 3950592   76% /opt

Logical Volume details

lvdisplay shows the details of the logical volume like LV Name, VG Name, LV Size, Allocated PE etc.

# lvdisplay /dev/vg00/lvol5
--- Logical volumes ---
LV Name                     /dev/vg00/lvol5
VG Name                     /dev/vg00
LV Permission               read/write
LV Status                   available/syncd
Mirror copies               0
Consistency Recovery        MWC
Schedule                    parallel
LV Size (Mbytes)            16384
Current LE                  512
Allocated PE                512
Stripes                     0
Stripe Size (Kbytes)        0
Bad block                   on
Allocation                  strict
IO Timeout (Seconds)        default

Volume Group Details

vgdisplay shows the details of the Volume group like VG Name, PE Size, Total PE, Allocated PE, Free PE etc. Volume Group vg00 has a total of 4451 PE in which 1411 PEs are free and PE size is 32 MB. We can allocate the free PE to any logical volume.

# vgdisplay vg00
--- Volume groups ---
VG Name                     /dev/vg00
VG Write Access             read/write
VG Status                   available
Max LV                      255
Cur LV                      8
Open LV                     8
Max PV                      16
Cur PV                      1
Act PV                      1
Max PE per PV               4461
VGDA                        2
PE Size (Mbytes)            32
Total PE                    4451
Alloc PE                    3040
Free PE                     1411
Total PVG                   0
Total Spare PVs             0
Total Spare PVs in use      0
VG Version                  1.0
VG Max Size                 2284032m
VG Max Extents              71376

Checking the possibility of resizing the volume online

To resize any volume online we need online JFS. It can be checked by using the command given below which will list the installed online JFS software if installed. In my server, Online JFS is already installed. If online JFS is not installed on your server then you can not resize the volume online, in this case, first, you need to umount the logical volume and the commands are also different.

# swlist -l product | grep -i jfs
  AONLINEJFS                    B.05.10.01     OnlineJFS 5.1SP1 Integration Product
  JFS                           B.11.31        Base VxFS File System 4.1 for HP-UX
  OnlineJFS01                   5.1.200.000    Online features of the VxFS File System
#

You can check the users who are accessing any mount point at a particular moment by using the command fuser -cu.

# fuser -cu /opt
/opt:     1113mt(root)    1646mt(sfmdb)    2529mt(sfmdb)    1647mt(sfmdb

Extend the Logical Volume

The current size of the logical volume /dev/vg00/lvol5 is 16 GB and I need to extend it to 18 GB. I have to give the size of the extended logical volume in MB with lvextend command.

# lvextend -L 18432 /dev/vg00/lvol5
Logical volume "/dev/vg00/lvol5" has been successfully extended.
Volume Group configuration for /dev/vg00 has been saved in /etc/lvmconf/vg00.conf
#

18432 is the size (in MB) of the extended logical volume. 18 GB = 18*1024 MB = 18432 MB

Logical Volume (LV) details after extending

Now it can be seen that allocated PE to /dev/vg00/lvol5 has been increased from 512 to 576.

# lvdisplay /dev/vg00/lvol5
--- Logical volumes ---
LV Name                     /dev/vg00/lvol5
VG Name                     /dev/vg00
LV Permission               read/write
LV Status                   available/syncd
Mirror copies               0
Consistency Recovery        MWC
Schedule                    parallel
LV Size (Mbytes)            18432
Current LE                  576
Allocated PE                576
Stripes                     0
Stripe Size (Kbytes)        0
Bad block                   on
Allocation                  strict
IO Timeout (Seconds)        default

Extend the File System

In the final step, we have to extend the file system by using the command fsadm. Here size of the volume given in KB and /opt is the mount point for /dev/vg00/lvol5.

# fsadm -b 18874368 /opt
fsadm: /etc/default/fs is used for determining the file system type
UX:vxfs fsadm: INFO: V-3-25942: /dev/vg00/rlvol5 size increased from 16777216 sectors to 18874368 sectors
#
16 GB = 16*1024 MB = 18432*1024 KB = 18874368 KB

Verify the Extended Volume

Use the bdf command to verify the size of the Logical Volume (LV)

# bdf /opt
Filesystem          kbytes    used   avail %used Mounted on
/dev/vg00/lvol5    16777216 12807008 3950592   76% /opt

Note: I have done these activities on HP-UX 11.31

Last Updated: Apr 14, 2018