umount -f /backup1
vi /etc/filesystems
/backup1:
dev = /vol/ERP1
vfs = nfs
nodename = 10.135.8.12
mount = true
options = rw,bg,hard,intr,proto=tcp,vers=3,rsize=65536,wsize=65536,timeo=600
account = false
mount /backup1
原文：http://my.oschina.net/dddpeter/blog/490568