Renaming LV Online now possible on AIX 6.1 TL4 onwards

TL4 for AIX 6.1 now allows you to rename logical volumes (LV) while they are still online i.e. open.

# oslevel -s

6100-04-01-0944

Rename the logical volume for the /home/nmon filesystem. The original LV name was nmonlv.

# df -m /home/nmon
Filesystem    MB blocks      Free %Used    Iused %Iused Mounted on
/dev/nmonlv      256.00    254.73    1%       23     1% /home/nmon

# lsvg -l rootvg | grep nmon
nmonlv              jfs2       1       1       1    open/syncd    /home/nmon

Change the LV name to nmon_lv.
# chlv -n nmon_lv nmonlv

The df command did not show any change i.e. it still displayed the old LV name. As expected.
# df -m /home/nmon

Filesystem    MB blocks      Free %Used    Iused %Iused Mounted on
/dev/nmonlv      256.00    254.73    1%       23     1% /home/nmon

However, the lsvg command confirmed that the LV name had indeed changed. As did the stanza in /etc/filesystems.

# lsvg -l rootvg | grep nmon
nmon_lv             jfs2       1       1       1    open/syncd    /home/nmon

# grep -p nmon /etc/filesystems
/home/nmon:
        dev             = /dev/nmon_lv
        vfs             = jfs2
        log             = /dev/hd8
        mount           = true
        options         = rw
        account         = false
        quota           = no

After re-mounting the filesystem, the df command now displayed the new LV name.
# umount /home/nmon
# mount /home/nmon
# df /home/nmon

Filesystem    512-blocks      Free %Used    Iused %Iused Mounted on
/dev/nmon_lv      524288    521696    1%       23     1% /home/nmon

Not a big deal you say? Well, prior to TL4, I would have to unmount the filesystem first and then change the LV name. e.g.

# oslevel -s
6100-02-02-0849

# chlv -n nmon_lv nmonlv
0516-708 chlv: Cannot rename open logical volume. If LV
        contains a filesystem, unmount to close logical volume nmonlv.

Just another enhancement to the usability features of the AIX operating system.
Not as impressive as being able to shrink a filesystem ‘on-the-fly’, but it’s certainly making life easier for AIX administrators.