for the filesystem you want to unmount, do
fuser -cu /mount_pount
this will list the users currently using the mount point. If you cannot logout those users, do
fuser -ck /mount_point
Sometimes processes do not show under ‘fuser /filesystem
Try using ‘fuser /dev/vgXX/lvolX’
Best thing is to use the logical volume name instead of the mount point.
#fuser -v /dev/vgxx/lvolxx
If these pids are not corresponding to any important processes, then
#fuser -k /dev/vgxx/lvolxx
#mount /mount_point
UNIX95=x ps -efH | more