Use the umount command to unmount a currently mounted file system.
See the vxumount(1M) manual page.
To unmount a file system
Specify the file system to be unmounted as a mount_point or special. special is the VxFS block special device on which the file system resides.
The following is an example of unmounting a file system.
Example of unmounting a file system
# umount /dev/vx/dsk/fsvol/vol1