Centos7 下 mysql5.7-mmm 高可用群集
MMM介绍
MMM( Master- Master replication manager for MYSQL, MYSQL主主复制管理器)
是一套支持双主故障切换和双主日常管理的脚本程序。MMM使用Perl语言开发,主要用来监控和管理 MYSQL master-master(双主)复制,虽然叫做双主复制,但是业务上同一时刻只允许对一个主进行写入,另一台备选主上提供部分读服务,以加速在主主切换时备选主的预热,可以说MMM这套脚本程序一方面实现了故障切换的功能
另一方面其内部附加的工具脚本也可以实现多个 Slave的read负载均衡。
实验准备
4台安装mysql5.7服务的设备
1台用来安装mmm的centos7设备
实验步骤
关闭防火墙自启动，以及相关功能和增强性安全功能
systemctl stop firewalld.service
setenforce 0配置ALI云源，然后安装epel-release源。
wget -O /etc/yum.repos.d/CentOS-Base.repo http://mirrors.aliyun.com/repo/Centos-7.repo
yum -y install epel-release
yum clean all && yum makecache修改mysql服务器的配置文件
vim /etc/my.cnf
修改mysqld下面的内容
[mysqld]
log_error=/var/lib/mysql/mysql.err
log=/var/lib/mysql/mysql_log.log
log_slow_queries=/var/lib/mysql_slow_queris.log
binlog-ignore-db=mysql,information_schema
character_set_server=utf8
log_bin=mysql_bin
server_id=1
log_slave_updates=true
sync_binlog=1
auto_increment_increment=2
auto_increment_offset=1
systemctl restart mysqld
-------没有问题后，把配置文件复制到其它3台数据库服务器上并启动服务器-----
scp /etc/my.cnf [email protected]:/etc/
scp /etc/my.cnf [email protected]:/etc/
scp /etc/my.cnf [email protected]:/etc/
-----注意：配置文件中的server_id 要修改-----
配置主主复制,两台主服务器相互复制
show master status;
+-------------------+----------+--------------+------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+-------------------+----------+--------------+------------------+
| master-bin.000002 | 339 | | |
+-------------------+----------+--------------+------------------+
1 row in set (0.00 sec) ##记录日志文件名称和 位置值，在两台主上查看。
----在m1上为m2授予从的权限，在m2上也要为m1授予从的权限---
grant replication slave on *.* to 'replication'@'192.168.100.%' identified by '123456'; ##两台主服务器都执行，从服务器不需要
change master to master_host='192.168.100.101',master_user='replication',master_password='123456',master_log_file='mysql_bin.000002',master_log_pos=339;
-----注意，在m1上要指定m2上的日志文件名，和位置参数-----在m2上要反过来。
start slave;
show slave status;
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
-------在另一台主上做----要指定m1的日志和位置参数---
change master to master_host='192.168.100.100',master_user='replication',master_password='123456',master_log_file='mysql_bin.000002',master_log_pos=339;
start slave;
show slave status;
Slave_IO_Running: Yes
Slave_SQL_Running: Yes配置主从复制
change master to master_host='192.168.100.100',master_user='replication',master_password='123456',master_log_file='mysql_bin.000002',master_log_pos=339;
start slave;
show slave status;
Slave_IO_Running: Yes
Slave_SQL_Running: Yes安装MMM
在所有服务器上安装-----注意，epel源要配置好
yum -y install mysql-mmm*配置mmm
cd /etc/mysql-mmm/
vi mmm_common.conf ##所有主机上都要配置,直接复制多份
<host default>
cluster_interface ens33
……
replication_user replication
replication_password 123456
agent_user mmm_agent
agent_password 123456
<host db1>
ip 192.168.100.100
mode master
peer db2
</host>
<host db2>
ip 192.168.100.101
mode master
peer db1
</host>
<host db3>
ip 192.168.100.102
mode slave
</host>
<host db4>
ip 192.168.100.103
mode slave
</host>
<role writer>
hosts db1, db2
ips 192.168.100.200
mode exclusive
</role>
<role reader>
hosts db3, db4
ips 192.168.100.201, 192.168.100.202
mode balanced
</role>
scp mmm_common.conf [email protected]:/etc/mysql-mmm/
scp mmm_common.conf [email protected]:/etc/mysql-mmm/
scp mmm_common.conf [email protected]:/etc/mysql-mmm/
scp mmm_common.conf [email protected]:/etc/mysql-mmm/ ## 复制给mysql服务器
------------------在monitor服务器上配置----
cd /etc/mysql-mmm/ //改密码
vi mmm_mon.conf
<host default>
monitor_user mmm_monitor
monitor_password 123456
</host>
--------------在所有数据库上为mmm_agent授权-----
grant super, replication client, process on *.* to 'mmm_agent'@'192.168.100.%' identified by '123456';
--------------在所有数据库上为mmm_moniter授权-----
grant replication client on *.* to 'mmm_monitor'@'192.168.100.%' identified by '123456';
flush privileges;
---------------修改所有数据库的mmm_agent.conf----
vi /etc/mysql-mmm/mmm_agent.conf
this db1 ##主1 主2 从1 从2 分别为 db{1,2,3,4}
--------------在所有数据库服务器上启动mysql-mmm-agent---
systemctl start mysql-mmm-agent.service
systemctl enable mysql-mmm-agent.service
------------------在monitor服务器上配置------
cd /etc/mysql-mmm/
vi mmm_mon.conf
……
ping_ips 192.168.100.100,192.168.100.101,192.168.100.102,192.168.100.103 ##数据库服务器地址
auto_set_online 10
systemctl start mysql-mmm-monitor.service ##启动mysql-mmm-monitor
mmm_control show ##查看各节点的情况
db1(192.168.100.100) master/ONLINE. Roles: writer(192.168.100.200)
db2(192.168.100.101) master/ONLINE. Roles:
db3(192.168.100.102) slave/ONLINE. Roles: reader(192.168.100.201)
db4(192.168.100.103) slave/ONLINE. Roles: reader(192.168.100.202)
mmm_control checks all ## 需要各种OK
mmm_control move_role writer db1 ##手动转换角色
测试
关掉主1 的mysql服务
systemctl stop mysqld
mmm_control show ##查看各节点的情况
db1(192.168.100.100) master/HARD_OFFLINE. Roles:
db2(192.168.100.101) master/ONLINE. Roles: writer(192.168.100.200)
db3(192.168.100.102) slave/ONLINE. Roles: reader(192.168.100.201)
db4(192.168.100.103) slave/ONLINE. Roles: reader(192.168.100.202)
关掉从1的mysql服务
mmm_control show ##查看各节点的情况
db1(192.168.100.100) master/HARD_OFFLINE. Roles:
db2(192.168.100.101) master/ONLINE. Roles: writer(192.168.100.200)
db3(192.168.100.102) slave/HARD_OFFLINEE. Roles:
db4(192.168.100.103) slave/ONLINE. Roles: reader(192.168.100.201，192.168.100.202)