1. trouble: if the NFS server is unreachable

[root@alice-serv1 init.d]# ./autofs restart
Stopping automount:umount2: Device or resource busy
umount: /misc: device is busy
                                                           [FAILED]
Starting automount:
failed to load map: "/usr/sbin/automount --timeout=60 /misc[FAILED].misc -hard,intr,bg,rsize=8192,wsize=8192"
[root@alice-serv1 /]# umount /misc/home
umount: /misc/home: device is busy
umount: /misc/home: device is busy
[root@alice-serv1 /]# ll /misc/home
ls: /misc/home: Stale NFS file handle
[root@alice-serv1 /]# umount -f /misc/home
umount2: Device or resource busy
umount: /misc/home: device is busy
umount2: Device or resource busy
umount: /misc/home: device is busy
[root@alice-serv1 /]# umount -l /misc/home