NFS介绍：
NFS（Network File System）即网络文件系统，是FreeBSD支持的文件系统中的一种，它允许网络中的计算机之间通过TCP/IP网络共享资源。在NFS的应用中，本地NFS的客户端应用可以透明地读写位于远端NFS服务器上的文件，就像访问本地文件一样。
实战案例
NFS+DRBD+HEARTBEAT
1.环境描述
OS：
NFS-MASTER:
centos6.5
IP:
eth0:172.16.50.199 #管理ip
eth1:10.0.0.1 #内网直连ip
VIP:172.16.50.249
软件:
NFS
DRBD
hearteat
NFS-BACKUP:
centos6.5
IP:
eth0:172.16.50.193
eth1:10.0.0.2
VIP:172.16.50.249
软件:
NFS
DRBD
hearteat
描述：
本案例假设有2台NFS存储系统服务器NFS-master、NFS-backup，其实际IP分别为172.16.50.199、172.16.50.193
NFS-master的NFS存储系统文件目录为/data，对前端提供的访问VIP为172.16.50.249
配置目标：一旦NFS存储系统服务器NFS-master宕机，该服务器上的NFS存储系统服务和虚拟IP会自动切换到热备服务器NFS-backup上继续提供服务，从而达到NFS存储系统高可用宕机后无业务影响的目的
这里有一个特别的问题，就是以前的多个从NFS存储系统如何能自动和新的主NFS存储系统同步，经过实践，通过drbd的方式同步的数据NFS存储系统，以及做从NFS存储系统时使用和主NFS存储系统对外提供服务的VIP为同步VIP，当主NFS存储系统宕机后，VIP漂移到热备主NFS存储系统，默认情况在几秒内，新的主NFS存储系统就可以启动同步程序同步到所有的从NFS存储系统中
2准备工作
两个都加一块硬盘，master 2G，backup 4G，用于存放数据
MASTER：
[root@localhost /]# /etc/init.d/iptables stop
[root@localhost /]# setenforce 0 #永久关闭，修改selinux文件
[root@localhost /]# hostname NFS-master #永久修改，修改network文件
[root@NFS-master /]# bash
[root@NFS-master /]# route add -host 10.0.0.2 dev eth1 #路由，模拟心跳线直连
[root@NFS-master /]# echo "10.0.0.1 NFS-master" >> /etc/hosts
[root@NFS-master /]# echo "10.0.0.2 NFS-backup" >> /etc/hosts
[root@NFS-master /]# echo '/sbin/route add -host 10.0.0.2 dev eth1' >> /etc/rc.local
BACKUP：
[root@localhost /]# /etc/init.d/iptables stop
[root@localhost /]# setenforce 0
[root@localhost /]# hostname NFS-backup
[root@NFS-backup /]# bash
[root@NFS-backup /]# route add -host 10.0.0.1 dev eth1
[root@NFS-backup /]# echo "10.0.0.1 NFS-master" >> /etc/hosts
[root@NFS-backup /]# echo "10.0.0.2 NFS-backup" >> /etc/hosts
[root@NFS-backup /]# echo '/sbin/route add -host 10.0.0.1 dev eth1' >> /etc/rc.local
安装heartbeat
#快速安装heartbeat
#这里使用yum安装
MASTER：
1.下载并安装epel包
[root@NFS-master /]# wget -q http://mirrors.ustc.edu.cn/fedora/epel/6/x86_64/epel-release-6-8.noarch.rpm
[root@NFS-master /]# [ -f epel-release-6-8.noarch.rpm ] && rpm -ivh epel-release-6-8.noarch.rpm || echo "失败"
[root@NFS-master /]# rpm -qa | grep epel
2.安装heartbeat
[root@NFS-master /]# yum -y install heartbeat
3.配置heartbeat
[root@NFS-master /]# cd /etc/ha.d/
[root@NFS-master ha.d]# cp /usr/share/doc/heartbeat-3.0.4/ha.cf .
[root@NFS-master ha.d]# cp /usr/share/doc/heartbeat-3.0.4/authkeys .
[root@NFS-master ha.d]# cp /usr/share/doc/heartbeat-3.0.4/haresources .
[root@NFS-master ha.d]# cat ha.cf
logfacility local0
debugfile /var/log/ha-debug
logfile /var/log/ha.log
logfacility local1
keepalive 2
deadtime 30
warntime 10
initdead 60
#bcast eth1
mcast eth1 225.0.0.250 694 1 0
auto_failback on
node NFS-master
node NFS-backup
crm no
#the end by Daniel
[root@NFS-master ha.d]# cat authkeys
auth 1
1 sha1 Hello
[root@NFS-master ha.d]# cat haresources
NFS-master IPaddr::172.16.50.249/24/eth0
NFS-backup IPaddr::172.16.50.250/24/eth0
[root@NFS-backup ha.d]# chmod 600 authkeys
BACKUP：
1.下载并安装epel包
[root@NFS-backup /]# wget -q http://mirrors.ustc.edu.cn/fedora/epel/6/x86_64/epel-release-6-8.noarch.rpm
[root@NFS-backup /]# [ -f epel-release-6-8.noarch.rpm ] && rpm -ivh epel-release-6-8.noarch.rpm || echo "失败"
[root@NFS-backup /]# rpm -qa | grep epel
2.安装heartbeat
[root@NFS-backup /]# yum -y install heartbeat
3.配置heartbeat
[root@NFS-backup /]# cd /etc/ha.d/
[root@NFS-backup ha.d]# cp /usr/share/doc/heartbeat-3.0.4/ha.cf .
[root@NFS-backup ha.d]# cp /usr/share/doc/heartbeat-3.0.4/authkeys .
[root@NFS-backup ha.d]# cp /usr/share/doc/heartbeat-3.0.4/haresources .
[root@NFS-backup ha.d]# cat ha.cf
logfacility local0
debugfile /var/log/ha-debug
logfile /var/log/ha.log
logfacility local1
keepalive 2
deadtime 30
warntime 10
initdead 60
#bcast eth1
mcast eth1 225.0.0.250 694 1 0
auto_failback on
node NFS-master
node NFS-backup
crm no
#the end by Daniel
[root@NFS-backup ha.d]# cat authkeys
auth 1
1 sha1 Hello
[root@NFS-backup ha.d]# cat haresources
NFS-master IPaddr::172.16.50.249/24/eth0
NFS-backup IPaddr::172.16.50.250/24/eth0
[root@NFS-master ha.d]# chmod 600 authkeys
#启动heartbeat
/etc/init.d/heartbeat start
安装drbd
1.硬盘分区
[root@NFS-master /]# parted /dev/sdb mklabel gpt #修改成gpt分区格式
[root@NFS-master /]# parted /dev/sdb mkpart primary 0 1024 #分一个主分区大小1024
[root@NFS-master /]# parted /dev/sdb mkpart primary 1025 2146
[root@NFS-master /]# parted /dev/sdb p
Model: VMware, VMware Virtual S (scsi)
Disk /dev/sdb: 2147MB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Number Start End Size File system Name 标志
1 17.4kB 1024MB 1024MB primary
2 1024MB 2147MB 1123MB primary
#backup，1分区0 2048，2分区2049 4292
[root@NFS-backup /]# parted /dev/sdb p
Model: VMware, VMware Virtual S (scsi)
Disk /dev/sdb: 4295MB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Number Start End Size File system Name 标志
1 17.4kB 2048MB 2048MB primary
2 2049MB 4292MB 2243MB primary
2.安装drbd
#yum安装
[root@NFS-master /]# mkdir /root/downloads
[root@NFS-master /]# cd /root/downloads/
[root@NFS-master downloads]# wget -q http://www.elrepo.org/elrepo-release-6-8.el6.elrepo.noarch.rpm
[root@NFS-master downloads]# rpm -ivh elrepo-release-6-8.el6.elrepo.noarch.rpm
[root@NFS-master downloads]# yum -y install drbd kmod-drbd84
[root@NFS-master downloads]# modprobe drbd
#如果这步报错：FATAL: Module drbd not found.则yum -y install kernel kernel-devel kernel-headers,然后重启，再次modprobe drbd
[root@NFS-master ~]# echo '/sbin/modprobe drbd' >>/etc/rc.local
3.配置drbd配置文件
[root@NFS-master ~]# cat /etc/drbd.conf
global {
usage-count no;
}
common {
syncer {
rate 100M;
verify-alg crc32c;
}
}
#primary for drbd1
resource data {
protocol C;
disk {
on-io-error detach;
}
on NFS-master {
device /dev/drbd0;
disk /dev/sdb1;
address 10.0.0.1:7788;
meta-disk /dev/sdb2[0];
}
on NFS-backup {
device /dev/drbd0;
disk /dev/sdb1;
address 10.0.0.2:7788;
meta-disk /dev/sdb2[0];
}
}
[root@NFS-master ~]# drbdadm create-md data
[root@NFS-master ~]# drbdadm up data
[root@NFS-master ~]# cat /proc/drbd
version: 8.4.9-1 (api:1/proto:86-101)
GIT-hash: 9976da086367a2476503ef7f6b13d4567327a280 build by mockbuild@Build64R6, 2016-12-13 18:38:15
0: cs:Connected ro:Secondary/Secondary ds:Inconsistent/Inconsistent C r-----
ns:0 nr:0 dw:0 dr:0 al:8 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:f oos:999984
3.设置主，同步数据到对端
[root@NFS-master ~]# drbdadm -- --overwrite-data-of-peer primary data
[root@NFS-master ~]# cat /proc/drbd
version: 8.4.9-1 (api:1/proto:86-101)
GIT-hash: 9976da086367a2476503ef7f6b13d4567327a280 build by mockbuild@Build64R6, 2016-12-13 18:38:15
0: cs:Connected ro:Primary/Secondary ds:UpToDate/UpToDate C r-----
ns:999983 nr:0 dw:0 dr:1000662 al:8 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:f oos:0
[root@NFS-master ~]# mkfs.ext4 -b 4096 /dev/drbd0 #格式化分区
[root@NFS-master ~]# tune2fs -c -1 /dev/drbd0
4.挂载测试
[root@NFS-master ~]# mkdir /md1
[root@NFS-master ~]# cd /md1
[root@NFS-master md1]# for n in `seq 10`;do cp /bin/cat daniel$n;done #写入操作
#以上操作在master上操作（3、4）
#接下来在backup上操作
[root@NFS-backup ~]# drbdadm down data
[root@NFS-backup ~]# mkdir /md1
[root@NFS-backup ~]# mount /dev/sdb1 /md1/ #然后查看/md1下，确实已经同步了
配合heartbeat调试drbd服务
需要执行相关切换命令确保heartbeat服务及drbd服务之间的配合是正确的才能继续向下进行。这类似项目阶段的里程碑，成功配置drbd服务，并且能配合heartbeat服务进行主备切换是第二步的关键
1.配置haresource
umount /md1
[root@NFS-master ha.d]# /etc/init.d/heartbeat stop #两边都要停掉
[root@NFS-master ~]# cat /etc/ha.d/haresources
NFS-master IPaddr::172.16.50.249/24/eth0 drbddisk::data Filesystem::/dev/drbd0::/data::ext4
NFS-backup IPaddr::172.16.50.250/24/eth0
#NFS-master：主机名
#IPaddr：VIP/掩码/网卡
#drbddisk：就是数据名data
#Filesystem：逻辑设备drbd0:，同步数据data，文件类型ext4
#两边都要配置
#启动
[root@NFS-master ~]# /etc/init.d/heartbeat start #先在master启动
#测试
关掉master，最好是使用暂停虚拟机的方式，我们模拟一下裂脑
查看backup
[root@NFS-backup /]# cat /proc/drbd
version: 8.4.9-1 (api:1/proto:86-101)
GIT-hash: 9976da086367a2476503ef7f6b13d4567327a280 build by mockbuild@Build64R6, 2016-12-13 18:38:15
0: cs:WFConnection ro:Primary/Unknown ds:UpToDate/DUnknown C r-----
ns:4100 nr:57975 dw:57995 dr:6204 al:1 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:f oos:4
[root@NFS-backup /]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda2 15G 4.4G 9.6G 32% /
tmpfs 426M 4.0K 426M 1% /dev/shm
/dev/sda1 93M 63M 26M 72% /boot
/dev/sda5 178G 60M 169G 1% /home
/dev/drbd0 946M 1.7M 895M 1% /data
#这里也自动挂载了，成为了主
[root@NFS-backup /]# ip addr|grep 172
inet 172.16.50.193/24 brd 172.16.50.255 scope global eth0
inet 172.16.50.250/24 brd 172.16.50.255 scope global secondary eth0
inet 172.16.50.249/24 brd 172.16.50.255 scope global secondary eth0
启动master
再次查看
就会发现两端的drbd都说对方是Unknown
#解决
先关掉两边的heartbeat
从节点做如下操作
modprobe drbd
drbdadm secondary data
drbdadm up data
drbdadm disconnect data
drbdadm -- --discard-my-data connect data
[root@NFS-backup /]# cat /proc/drbd
version: 8.4.9-1 (api:1/proto:86-101)
GIT-hash: 9976da086367a2476503ef7f6b13d4567327a280 build by mockbuild@Build64R6, 2016-12-13 18:38:15
0: cs:Connected ro:Secondary/Primary ds:UpToDate/UpToDate C r-----
ns:0 nr:4 dw:58003 dr:6204 al:1 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:f oos:0
主节点做如下操作
[root@NFS-master /]# drbdadm connect data
#两边再次启动heartbeat，再次查看
[root@NFS-master /]# cat /proc/drbd
version: 8.4.9-1 (api:1/proto:86-101)
GIT-hash: 9976da086367a2476503ef7f6b13d4567327a280 build by mockbuild@Build64R6, 2016-12-13 18:38:15
0: cs:Connected ro:Primary/Secondary ds:UpToDate/UpToDate C r-----
ns:8 nr:0 dw:28 dr:3866 al:1 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:f oos:0
[root@NFS-master /]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda5 15G 486M 14G 4% /
tmpfs 426M 80K 426M 1% /dev/shm
/dev/sda6 90G 56M 85G 1% /home
/dev/sda3 79G 3.9G 71G 6% /usr
/dev/sda1 9.8G 349M 8.9G 4% /var
/dev/drbd0 946M 1.7M 895M 1% /data
[root@NFS-master /]# ip addr | grep 172
inet 172.16.50.199/24 brd 172.16.50.255 scope global eth0
inet 172.16.50.249/24 brd 172.16.50.255 scope global secondary eth0
#再次查看发现好了
安装NFS
#安装
root@NFS-master ~]# yum -y install nfs-utils rpcbind #两端操作，一起安装
#启动
[root@NFS-master ~]# /etc/init.d/rpcbind start
[root@NFS-master ~]# /etc/init.d/nfs start
[root@NFS-master ~]# chkconfig rpcbind on
[root@NFS-master ~]# chkconfig nfs on
#两端操作
#配置
[root@NFS-master ~]# cat /etc/exports
/data 10.0.0.*(rw,sync) #data是同步目录，rw读写，sync同步
[root@NFS-backup /]# /etc/init.d/nfs reload
[root@NFS-master ~]# showmount -e 10.0.0.1
Export list for 10.0.0.1:
/data 10.0.0.*
#两端操作，backup showmount -e 10.0.0.2,其他一样
配置客户端挂载
#客户端
IP：10.0.0.3
service rpcbind start #开启rpcbind
chkconfig rpcbind on
showmount -e 172.16.50.249
#如果单网卡的话，则route add -host 172.16.50.249 dev eth0
mkdir /data
mount -t nfs 172.16.50.249:/data /data
ls /data #发现有了
touch 1 #测试一下，如果不行就在master上给足权限777，生产环境就要只能给nfs用户
#测试高可用
#关闭master
#查看backup
[root@NFS-backup /]# ip addr| grep 172
inet 172.16.50.193/24 brd 172.16.50.255 scope global eth0
inet 172.16.50.250/24 brd 172.16.50.255 scope global secondary eth0
inet 172.16.50.249/24 brd 172.16.50.255 scope global secondary eth0
[root@NFS-backup /]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda2 15G 4.4G 9.6G 32% /
tmpfs 426M 4.0K 426M 1% /dev/shm
/dev/sda1 93M 63M 26M 72% /boot
/dev/sda5 178G 60M 169G 1% /home
/dev/drbd0 946M 1.7M 895M 1% /data
[root@NFS-backup /]# cat /proc/drbd
version: 8.4.9-1 (api:1/proto:86-101)
GIT-hash: 9976da086367a2476503ef7f6b13d4567327a280 build by mockbuild@Build64R6, 2016-12-13 18:38:15
0: cs:WFConnection ro:Primary/Unknown ds:UpToDate/DUnknown C r-----
ns:8 nr:4228 dw:4272 dr:1532 al:2 bm:0 lo:0 pe:0 ua:0 ap:0 ep:1 wo:f oos:32
#没有问题
#再次写入东西，然后查看
#master的heartbeat最好还是不要启动
使用exports
#使用exportfs
#master
[root@NFS-master ~]# cat /etc/exports
#/md1 10.0.0.*(rw,sync)
[root@NFS-master ~]# exportfs -o rw,sync,all_squash,anonuid=65534,anongid=65534,mp,fsid=2 10.0.0.0/24:/md1
[root@NFS-master ~]# showmount -e 10.0.0.1
Export list for 10.0.0.1:
/md1 10.0.0.*,10.0.0.0/24
#客户端
umount /md1
mount -t nfs 172.16.50.249:/md1 /md1
如果像前面一样，每次down机后都要自己重新挂载一遍nfs实在是麻烦，我们可以写个脚本
[root@NFS-backup ~]# vi /etc/ha.d/resource.d/rsmd1
FSID="1"
EXPORT_DIR="/md1"
EXPORT_OPTIONS="-o rw,sync,all_squash,anonuid=65534,anongid=65534,mp,fsid=$FSID"
EXPORT_CLIENTS="10.0.0.0/24"
exportfs_usage()
{
cat <<END
USAGE: $0 (start|stop)
END
}
exportfs_start()
{
fn="`/bin/mktemp`"
/etc/init.d/nfs restart
sleep 2
exportfs ${EXPORT_OPTIONS} ${EXPORT_CLIENTS}:${EXPORT_DIR} > $fn 2>&1
rc=$?
# error exportfs
if [ $rc -ne 0 ]; then
echo "export resource '${EXPORT_DIR}' error."
exit $rc
fi
rm -f $fn
echo "export resource '${EXPORT_DIR}' ok."
exit 0
}
exportfs_stop()
{
fn="`/bin/mktemp`"
/etc/init.d/nfs restart
exportfs -u ${EXPORT_CLIENTS}:${EXPORT_DIR} > $fn 2>&1
rc=$?
if [ $? -eq 0 ]; then
echo "unexport resource ${EXPORT_DIR} ok."
exit 0
fi
rm -f $fn
echo "unexport resource ${EXPORT_DIR} error."
exit $rc
}
if [ $# -ne 1 ]; then
exportfs_usage
exit 1
fi
case $1 in
start)
exportfs_start
;;
stop)
exportfs_stop
;;
*)
exportfs_usage
exit 1
;;
esac
#这个脚本用于挂载nfs
我们怎么使用这个脚本呢？
[root@NFS-backup ~]# cat /etc/ha.d/haresources
NFS-master IPaddr::172.16.50.249/8/eth1 drbddisk::data Filesystem::/dev/drbd0::/md1::ext4 rsmd1
NFS-backup IPaddr::172.16.50.250/8/eth1
#这样就等于我们heartbeatdown掉后，备用接管的同时执行这个脚本，并且挂在上drbd0到md1