安装NFS服务

1.安装nfs服务器端与客户端
    $sudo apt-get install nfs-kernel-server nfs-common portmap
    安装客户端的作用是可以在本机进行nfs测试
2.配置portmap
    方法1：通过编辑/etc/default/portmap
    
    $sudo vi /etc/default/portmap
    1 # Portmap configuration file
    2 #
    3 # Note: if you manually edit this configuration file,
    4 # portmap configuration scripts will avoid modifying it
    5 # (for example, by running 'dpkg-reconfigure portmap').
    6
    7 # If you want portmap to listen only to the loopback
    8 # interface, uncomment the following line (it will be
    9 # uncommented automatically if you configure this
    10 # through debconf).
    11 #OPTIONS=""

    注释掉最后一行OPTIONS.

    方法2：
    $sudo dpkg-reconfigure portmap
    运行后选择.
    另外，要用sysv-rc-conf(不是chkconfig)工具查看一下当前nfs和portmap的     状态，若是off，则用sudo sysv-rc-conf portmap on 或 sudo sysv-rc-confnfs-    kernel-server on 打开。

3.配置挂载目录
    $sudo vi /etc/exports

    1 # /etc/exports: the access control list for filesystems which may be exporte    d
    2 #               to NFS clients.  See exports(5).
    3 #
    4 # Example for NFSv2 and NFSv3:
    5 # /srv/homes       hostname1(rw,sync,no_subtree_check) hostname2(ro,sync,no_    subtree_check)
    6 #
    7 # Example for NFSv4:
    8 # /srv/nfs4        gss/krb5i(rw,sync,fsid=0,crossmnt,no_subtree_check)
    9 # /srv/nfs4/homes  gss/krb5i(rw,sync,no_subtree_check)
    10 #
    11 /home/nfs/qemu-target-armv5l 192.168.200.*(rw,no_root_squash,subtree_check,async)
    做后一行是所需配置

4.创建共享文件夹
    sudo mkdir /home/nfs/qemu-target-armv5l

5.更新exports文件
    更改了/etc/exports之后，通过下面命令更新生效
    $sudo exportfs -r

6.重启nfs服务
    $sudo /etc/init.d/nfs-kernel-server restart

7.挂载
    $sudo mount -t nfs localhost:/home/nfs/qemu-target-armv5l /mnt

8.查看
    $showmount -e localhost

卸载NFS服务
    $sudo umount /mnt