how to unmount the locked file system in veritas?

procedure 1:

fist check mounted file system information

#mount -p

unmount file system by using umount command

#/opt/VRTSvcs/bin/umount -o mntunlock=vcs /mountpoint

still it shows bussy

#fuser -cu /mountpoint

#fuser -ck /mountpoint

#/opt/VRTSvcs/bin/umount -o mntunlock=vcs /mountpoint

still it through error

#/usr/lib/fs/vxfs/fsadm  -o mntlock=vcs /mounpoint

#/usr/lib/fs/vxfs/fsadm -o mntunlock=vcs /mountpoint

#/opt/VRTSvcs/bin/umount -o mntunlock=vcs /mountpoint

now it is unmounted