HP-UX file systems can be extended with a combination of the lvextend and fsadm commands. It’s well known procedure that has been in widespread use for several years, allowing online file system extensions, ie. the file system can be extended while it is mounted and busy. The file system type must be of type “vxfs” and enclosed in an LVM logical volume.

Occasional difficulties can occur if the file system is 100% full. I recently encountered the following vx_nospace error when trying to extend a file system from 9 Gb to 59 Gb under HP-UX 11.31.

# bdf
...
/dev/oravg/apps 9437184 9428618 8566 100% /u01/app/oracle
...

First to extend the logical volume to 59 Gb:

# lvextend -L 60416 /dev/oravg/apps
Logical volume "/dev/oravg/apps" has been successfully extended.
Volume Group configuration for /dev/oravg has been saved in /etc/lvmconf/oravg.conf

Now to extend the file system within it. The “-b” argument to fsadm is the size of the logical volume in kilobytes, which is the same as the new size of the file system.

# fsadm -F vxfs -b 61865984 /u01/app/oracle

vxfs: msgcnt 60164 mesg 001: V-2-1: vx_nospace - /dev/oravg/apps file system full (12800 block extent)

The solution was simply to free up some space in the file system, then repeat the fsadm command. I am not sure exactly how full the file system has to be in order for this error to occur. In this case, it might also have had something to do with the large relative size of the increase (9 Gb to 59 Gb) and the resulting small area in which to write new file system structures.