# umount /dev/dsk/c0t2d0s7 umount: /dev/dsk/c0t2d0s7: device is busy
The fuser command
can take two types of arguments:
You can use the -u option to the fuser statement to display the user ID’s
as well as PID’s in its output.
Lets look at a few examples. The following command will display all processes and their
associated users that are using files/directories on a specified disk on a Sun Solaris
system:
# fuser -u /dev/dsk/c0t2d0s7
/dev/dsk/c0t2d0s7: 1313co(oracle) 1223c(root)
lsof /media/cdrom --> worked for me.
http://www.idevelopment.info/data/Unix/General_UNIX/GENERAL_Troubleshootingthedeviceisbusy.shtml
http://wiki.linuxquestions.org/wiki/Umount