Comment 1 for bug 412351

When mounting with the "intr" option, you have to interrupt a stalled program (using Control-C in a terminal, for example) in order to get it to stop trying to access the server. If you instead mount with the "soft" option, NFS accesses will eventually time out without needing to be interrupted (but you may lose data if you were writing to the NFS filesystem -- the written data will not get saved anywhere because the server isn't responding.) When the server is hung, you should be able to unmount the server's filesystem using the -l (lazy) option (umount -l /opt/user1) to avoid future hangs.