I have a CIFS share mounted on a Linux machine. The CIFS server is down, or the internet connection is down, and anything that touches the CIFS mount now takes several minutes
I use lazy unmount: umount -l (that's a lowercase L)
Lazy unmount. Detach the filesystem
from the filesystem hierarchy now, and
cleanup all references to the
filesystem as soon as it is not busy
anymore. (Requires kernel 2.4.11 or
later.)