Linux NFS挂载报错wrong fs type, bad option, bad superblock

192.168.1.2:/mnt/HD/HD_a2/Public     /public nfs rw,bg,hard,nointr,rsize=32768,wsize=32768,tcp,actimeo=0,vers=3,timeo=600

mkdir /public
mount -a

[root@test04 ~]# mount -a
mount: wrong fs type, bad option, bad superblock on 192.168.1.2:/mnt/HD/HD_a2/Public,
       missing codepage or helper program, or other error
       (for several filesystems (e.g. nfs, cifs) you might
       need a /sbin/mount.<type> helper program)
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

[root@test04 ~]# yum install nfs-utils

[root@test04 ~]# mount -a
mount.nfs: rpc.statd is not running but is required for remote locking.
mount.nfs: Either use '-o nolock' to keep locks local, or start statd.
mount.nfs: an incorrect mount option was specified

[root@test04 ~]# service rpcbind status
rpcbind is stopped
[root@test04 ~]# service rpcbind start
Starting rpcbind:                                          [  OK  ]
[root@test04 ~]# chkconfig --list rpcbind
rpcbind         0:off   1:off   2:on    3:on    4:on    5:on    6:off

[root@test04 ~]# mount -a
[root@test04 ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg_test04-lv_root
                       18G  829M   16G   5% /
tmpfs                 939M     0  939M   0% /dev/shm
/dev/sda1             477M   39M  414M   9% /boot
192.168.1.2:/mnt/HD/HD_a2/Public
                      2.7T  1.6T  1.2T  57% /public