参考 CentOS 7 下 yum 安装和配置 NFS | Zhanming’s blog，补充整理部分内容
1. 环境说明
本文中的服务器环境如下：
| Role | Hostname | OS |
|---|---|---|
| NFS 服务端 | centos-2 |
CentOS 7.5 |
| NFS 客户端 | abelsu7-ubuntu |
Ubuntu 18.04 |
注：为简略起见，以下命令均以
root身份运行，省略sudo
2. NFS 服务端
2.1 安装 nfs-utils
注：对应的 Apt 包为
nfs-kernel-server和nfs-common
> yum info nfs-utils
Available Packages
Name : nfs-utils
Arch : x86_64
Epoch : 1
Version : 1.3.0
Release : 0.65.el7
Size : 412 k
Repo : base/7/x86_64
Summary : NFS utilities and supporting clients and daemons for the kernel NFS server
URL : http://sourceforge.net/projects/nfs
License : MIT and GPLv2 and GPLv2+ and BSD
Description : The nfs-utils package provides a daemon for the kernel NFS server and
: related tools, which provides a much higher level of performance than the
: traditional Linux NFS server used by most users.
:
: This package also contains the showmount program. Showmount queries the
: mount daemon on a remote host for information about the NFS (Network File
: System) server on the remote host. For example, showmount can display the
: clients which are mounted on that host.
:
: This package also contains the mount.nfs and umount.nfs program.
> yum install nfs-utils
# rpcbind 作为依赖会自动安装
2.2 配置并启动服务
允许rpcbind.service、nfs.service开机自启：
# 允许服务开机自启
> systemctl enable rpcbind
> systemctl enable nfs
启动相关服务：
# 启动相关服务
> systemctl start rpcbind
> systemctl start nfs
防火墙允许服务通过：
# 防火墙允许服务通过
> firewall-cmd --zone=public --permanent --add-service={rpc-bind,mountd,nfs}
success
> firewall-cmd --reload
success
2.3 配置共享目录
例如需要共享的目录为/mnt/kvm/：
# 创建 /mnt/kvm 并修改权限
> cd /mnt
/mnt > mkdir kvm
/mnt > chmod 755 kvm
# 验证目录权限
/mnt > ls -l
total 0
drwxr-xr-x 2 root root 59 Oct 17 17:49 kvm
之后修改/etc/exports，将/mnt/kvm/添加进去：
> cat /etc/exports
# 1. 只允许 abelsu7-ubuntu 访问
/mnt/kvm/ abelsu7-ubuntu(rw,sync,no_root_squash,no_all_squash)
# 2. 根据 IP 地址范围限制访问
/mnt/kvm/ 192.168.0.0/24(rw,sync,no_root_squash,no_all_squash)
# 3. 使用 * 表示访问不加限制
/mnt/kvm/ *(rw,sync,no_root_squash,no_all_squash)
关于/etc/exports中的参数含义：
/mnt/kvm/：需要共享的目录192.168.0.0/24：客户端 IP 范围，*表示无限制rw：权限设置，可读可写sync：同步共享目录no_root_squash：可以使用root授权no_all_squash：可以使用普通用户授权
保存之后，重启nfs服务：
> systemctl restart nfs
2.4 查看共享目录列表
在centos-2本地查看：
> showmount -e localhost
Export list for localhost:
/mnt/kvm abelsu7-ubuntu
3. NFS 客户端
3.1 安装 nfs-utils
# CentOS/Fedora, etc.
> yum install nfs-utils
# Ubuntu/Debian, etc.
> apt install nfs-common
3.2 配置并启动服务
设置rpcbind服务开机启动：
> systemctl enable rpcbind
启动rpcbind：
> systemctl start rpcbind
客户端不需要打开防火墙，也不需要开启 NFS 服务
3.3 挂载共享目录
先查看服务端的共享目录：
> showmount -e centos-2
Export list for centos-2:
/mnt/kvm abelsu7-ubuntu
在客户端创建并挂载对应目录：
> mkdir -p /mnt/kvm
> mount -t nfs centos-2:/mnt/kvm /mnt/kvm
最后检查一下是否挂载成功：
> df -hT /mnt/kvm
Filesystem Type Size Used Avail Use% Mounted on
centos-2:/mnt/kvm nfs4 500G 119G 382G 24% /mnt/kvm
> mount | grep /mnt/kvm
centos-2:/mnt/kvm on /mnt/kvm type nfs4 (rw,relatime,vers=4.2,rsize=1048576,wsize=1048576,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,clientaddr=222.xxx.xxx.xxx,local_lock=none,addr=116.xxx.xxx.xxx)
3.4 配置自动挂载
在客户端编辑/etc/fstab：
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
# / was on /dev/sda8 during installation
UUID=26d36e85-367a-4200-87fb-0505c5837078 / ext4 errors=remount-ro 0 1
# /boot/efi was on /dev/sda1 during installation
UUID=000E-274F /boot/efi vfat umask=0077 0 1
# swap was on /dev/sda9 during installation
# UUID=ee4da9a3-0288-4f8e-a86e-ab8ac3faa6bc none swap sw 0 0
# For nfs
centos-2:/mnt/kvm /mnt/kvm nfs defaults 0 0
最后重新加载systemctl，即可实现重启后自动挂载：
> systemctl daemon-reload
> mount | grep /mnt/kvm
centos-2:/mnt/kvm on /mnt/kvm type nfs4 (rw,relatime,vers=4.2,rsize=1048576,wsize=1048576,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,clientaddr=222.xxx.xxx.xxx,local_lock=none,addr=116.xxx.xxx.xxx)
4. NFS 读写速度测试
待更新…
> time dd if=/dev/zero of=/mnt/kvm-lun/test-nfs-speed bs=8k count=1024
> time dd if=/mnt/kvm-lun/test-nfs-speed of=/dev/null bs=8k count=1024
