Mysql+Corosync+Pacemaker+DRBD

1、环境介绍
OS：centos 6.5
kernel：2.6.32-431.11.2.el6.x86_64
node1:nginxha001 10.0.15.31 Master
node2:nginxha002 10.0.15.32 Slave
vip:10.0.15.30
说明：本例主要以drbd为主，涉及到mysql，corosync，pacemaker程序的安装请参考其他资料。程序两台都要安装，定义drbd资源可在一台上配置完毕复制到另外一台，创建磁盘需两台都创建，定义corosync资源只需在一台上配置即可，他会自动同步到另外一台。若程序连接mysql用虚拟ip即vip连接，最好是把程序也部署在drbd磁盘上，这样程序配置为localhost即可。

2、安装依赖包
yum -y install gcc rpm-build kernel-devel kernel-headers flex ncurses-devel

wget http://elrepo.org/linux/elrepo/el5/x86_64/RPMS/drbd84-utils-8.4.3-1.el5.elrepo.x86_64.rpm
wget http://elrepo.org/linux/elrepo/el6/x86_64/RPMS/kmod-drbd84-8.4.3-1.el6_4.elrepo.x86_64.rpm
yum -y install drbd84-utils-8.4.3-1.el5.elrepo.x86_64.rpm
yum install -y kmod-drbd84-8.4.3-1.el6_4.elrepo.x86_64.rpm

3、定义drbd资源
vi /etc/drbd.d/mysql.res #定义mysql资源，效果一样
resource mysql {
protocol C;
device /dev/drbd0;
disk /dev/sdc1;
meta-disk internal;
on nginxha001 {
address 10.0.15.31:7789;
}
on nginxha002 {
address 10.0.15.32:7789;
}
}

4、启动服务，并格式化磁盘
创建drbd数据同步所需的分区，两台电脑的空间要一样大
fdisk /dev/sdc
drbdadm create-md mysql
service drbd start

设置为主几点，仅在主节点上操作
drbdadm -- --overwrite-data-of-peer primary mysql
创建文件系统
mkfs -t ext4 /dev/drbd0

5、配置corosync资源
crm(live)# configure
property stonith-enabled=false
property no-quorum-policy=ignore
定义Mysql服务资源
primitive Mysqld lsb:mysqld
配置DRBD主从资源
primitive Drbd ocf:linbit:drbd params drbd_resource="mysql" op start interval="0" timeout="240" op stop interval="0" timeout="100"
master My_Drbd Drbd meta master-max="1" master-node-max="1" clone-max="2" clone-node-max="1" notify="true"
定义一个文件系统资源
primitive FileSys ocf:heartbeat:Filesystem params device="/dev/drbd0" directory="/mysqldata" fstype="ext4" op start timeout="60s" op stop timeout="60s"
定将资源之间的位置和启动顺序约束
#让文件系统与DRBD主节点运行在一起
colocation FileSys_on_My_Drbd inf: FileSys My_Drbd
#让DRBD服务比文件系统先启动
order FileSys_after_My_Drbd inf: My_Drbd:promote FileSys:start
#让Mysql服务与文件系统运行在一起
colocation Mysqld_on_FileSys inf: Mysqld FileSys
#让文件系统比Mysql服务先运行
order Mysqld_after_FileSys inf: FileSys Mysqld:start
#让虚拟IP与Mysql服务运行在一起
colocation vip_on_Mysqld inf: vip Mysqld

执行完毕后，最后的配置文件如下：
node nginxha001 \
attributes standby="off"
node nginxha002 \
attributes standby="off"
primitive Drbd ocf:linbit:drbd \
params drbd_resource="mysql" \
op monitor interval="10s" role="Master" \
op monitor interval="20s" role="Slave" \
op start timeout="240s" interval="0" \
op stop timeout="100" interval="0"
primitive FileSys ocf:heartbeat:Filesystem \
params device="/dev/drbd0" directory="/mysqldata" fstype="ext4" \
op start timeout="60s" interval="0" \
op stop timeout="60s" interval="0"
primitive Mysqld lsb:mysqld
primitive vip ocf:heartbeat:IPaddr \
params ip="10.1.15.30" nic="eth0" cidr_netmask="24" \
op monitor interval="10s"
ms My_Drbd Drbd \
meta master-max="1" master-node-max="1" clone-max="2" clone-node-max="1" notify="true"
colocation FileSys_on_My_Drbd inf: FileSys My_Drbd:Master
colocation Mysqld_on_FileSys inf: Mysqld FileSys
colocation vip_on_Mysqld inf: vip Mysqld
order FileSys_after_My_Drbd inf: My_Drbd:promote FileSys:start
order Mysqld_after_FileSys inf: FileSys Mysqld:start
property $id="cib-bootstrap-options" \
dc-version="1.1.10-14.el6_5.2-368c726" \
cluster-infrastructure="classic openais (with plugin)" \
expected-quorum-votes="4" \
stonith-enabled="false" \
no-quorum-policy="ignore" \
last-lrm-refresh="1396576217"
rsc_defaults $id="rsc-options" \
resource-stickiness="100"
#vim:set syntax=pcmk

若有有错误，执行如下命令清除错误即可
crm resource cleanup Mysqld
crm resource cleanup vip
crm resource cleanup FileSys

6、其他命令
挂载drbdo
mount /dev/drbd0 /mysqldata/
卸载
umount /mysqldata/
设置drbd为主，只有设置为主的才能挂载磁盘
drbdadm primary mysql
设置drbd为备用
drbdadm secondary mysql

watch -n1 'drbd-overview' 观察数据同步情况，ctrl+c退出。
drbd-overview #查看状态，当为下面内容时，进行下一步操作
cat /proc/drbd 查看同步进度

7、修改my.cnf配置，主要更改数据目录为drbd的目录
vi /etc/my.cnf

[mysqld]
datadir=/mysqldata
socket=/mysqldata/mysql.sock
user=mysql
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0

[mysqld_safe]
log-error=/mysqldata/mysqld.log
pid-file=/mysqldata/mysqld.pid
[client]
socket=/mysqldata/mysql.sock