umount issue

Unmount process :-

#umount  /data

The umount command scans the /etc/mnttab file and determine the Logical volume device file associated with the mount point to unmount it.

Some time we face the issue to umount the file system (“ Device busy” message when attempting to umount a file system)

# umount   /data

Umount:cannot unmount /data : Device busy

To determine who or what processes are using the file system use the fuser command :

# fuser –cu /data

/data: 2671c(root) 1141c(root)

The –c option tells the process ID and –u gives the username who the process ID.

You can kill all the processes using the file system by running the fuser command with –k option:

# fuser –ck /data

Or

We can use the –f switch with umount command to forcibly kill all processes using the file system and unmount it.

# umount –f /data