MMM实现mysql高可用性

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devops学习 2009-11-06 15:01:34 博主文章分类：Mysql ©著作权

文章标签 mysql 数据库休闲 MMM 高可用性 文章分类 MySQL 数据库

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由于mysql没有提供高可用性方案,如果一台数据库down就会影响到业务,为了实现高可用性可以使用hearbeat,这里我使用MMM来提高mysql的高可用性,以提高业务的不中断.

环境:

服务器类型 IP VIP

node1 10.10.1.65 10.10.1.77

node2 10.10.1.58 10.10.1.78

mon 10.10.1.161 10.10.1.79

配置过程:

1.首先要实现node1和node2的双向同步,这个本人博客已经有相关的文章,在这里就不进行说明了

2.安装和配置MMM

3台服务器都要安装MMM安装包,由于要使用到perl模块,所以要进行如下模块的安装

    Algorithm::Diff
    Proc::Daemon
    Time::HiRes
    DBI
    DBD::mysql

以上模块你可以通过cpan进行安装,也可以去cpan.org网站上去下载相应的安装包,我已经安装好了

MMM下载地址如下:http://code.google.com/p/mysql-master-master/downloads/list,现在

最新的安装是mysql-master-master-1.2.6.tar.gz.

#tar zxvf mysql-master-master-1.2.6.tar.gz

#cd mysql-master-master-1.2.6

#./install.pl

在nod1上的配置:

#cp usr/local/mmm/etc/examples/mmm_agent.conf.example mmm_agent.conf

#vi usr/local/mmm/etc/examples/mmm_agent.conf //这个配置文件的内容很少,直接清空

添加如下的内容

# 

     # Master-Master Manager config (agent) 

     # 

     # Debug mode 

     debug no //是否开启debug模式
     # Paths 

     pid_path /usr/local/mmm/var/mmmd_agent.pid //进程路径
     bin_path /usr/local/mmm/bin //执行命令路径
     # Logging setup 

     log mydebug 
     file /usr/local/mmm/var/mmm-debug.log //debug日志文件路径
     level debug 
     log mytraps 
     file /usr/local/mmm/var/mmm-traps.log 
     level trap 
     # MMMD command socket tcp-port and ip 

     bind_port 9989 
     # Cluster interface 

     cluster_interface eth0 //真实IP的接口
     # Define current server id 

     this db1
     mode master 
     # For masters 

     peer db2 
     # Cluster hosts addresses and access params 

     host db1 
     ip 10.10.1.65 //node1的真实IP
     port 3306 //数据库端口
     user rep_agent //如下创建的mysql用户
     password RepAgent //创建mysql用户的密码
     host db2 
     ip 10.10.1.58 //node2的真实IP 
     port 3306 
     user rep_agent 
     password RepAgent

#mysql -u root -p123456

GRANT ALL PRIVILEGES on *.* to 'rep_agent'@'%' identified by 'RepAgent';

GRANT ALL PRIVILEGES on *.* to 'rep_monitor'@'%' identified by
'RepMonitor';

在node2上的配置:

#cp usr/local/mmm/etc/examples/mmm_agent.conf.example mmm_agent.conf

#vi usr/local/mmm/etc/examples/mmm_agent.conf //这个配置文件的内容很少,直接清空

添加如下的内容

# 

    # Master-Master Manager config (agent) 

    # 

    # Debug mode 

    debug no 
    # Paths 

    pid_path /usr/local/mmm/var/mmmd_agent.pid 
    bin_path /usr/local/mmm/bin 
    # Logging setup 

    log mydebug 
    file /usr/local/mmm/var/mmm-debug.log 
    level debug 
    log mytraps 
    file /usr/local/mmm/var/mmm-traps.log 
    level trap 
    # MMMD command socket tcp-port and ip 

    bind_port 9989 
    # Cluster interface 

    cluster_interface eth0 
    # Define current server id 

    this db2
    mode master 
    # For masters 

    peer db1 
    # Cluster hosts addresses and access params 

    host db1 
    ip 10.10.1.65 
    port 3306 
    user rep_agent 
    password RepAgent 
    host db2 
    ip 10.10.1.58
    port 3306 
    user rep_agent 
    password RepAgent

#mysql -u root -p123456

GRANT ALL PRIVILEGES on *.* to 'rep_agent'@'%' identified by 'RepAgent';

GRANT ALL PRIVILEGES on *.* to 'rep_monitor'@'%' identified by
'RepMonitor';

在mon上的配置:

# Master-Master Manager config (monitor)

#

# Debug mode

debug no
# Paths

pid_path /usr/local/mmm/var/mmmd.pid
status_path /usr/local/mmm/var/mmmd.status
bin_path /usr/local/mmm/bin
# Logging setup

log mydebug
    file /usr/local/mmm/var/mmm-debug.log
    level debug
log mytraps
    file /usr/local/mmm/var/mmm-traps.log
    level trap
    email root@localhost

# MMMD command socket tcp-port

bind_port 9988
agent_port 9989
monitor_ip 127.0.0.1
# Cluster interface

cluster_interface eth0
# Cluster hosts addresses and access params

host db1
    ip 10.10.1.65 
    port 3306
    user rep_monitor
    password RepMonitor
    mode master
    peer db2
host db2
    ip 10.10.1.58
    port 3306
    user rep_monitor
    password RepMonitor
    mode master
    peer db1

#

# Define roles

#

active_master_role writer
# Mysql Reader role

role reader
    mode balanced
    servers db1, db2
    ip 10.10.1.77, 10.10.1.78    //这里是虚拟IP
# Mysql Writer role

role writer
    mode exclusive
    servers db1, db2
    ip 10.10.1.79               //这里是虚拟IP
#

# Checks parameters

#

# Ping checker

check ping
    check_period 1
    trap_period 5
    timeout 2
# Mysql checker

# (restarts after 10000 checks to prevent memory leaks)

check mysql
    check_period 1
    trap_period 2
    timeout 2
    restart_after 10000
# Mysql replication backlog checker

# (restarts after 10000 checks to prevent memory leaks)

check rep_backlog
    check_period 5
    trap_period 10
    max_backlog 60
    timeout 2
    restart_after 10000
# Mysql replication threads checker

# (restarts after 10000 checks to prevent memory leaks)

check rep_threads
    check_period 1
    trap_period 5
    timeout 2
    restart_after 10000

进行启动以及测试：

在node1和node2上启动mmmd_agent

#mmmd_agent

#netstat -tlnp

tcp 0 0 0.0.0.0:9989 0.0.0.0:* LISTEN 14301/perl
出现9989端口就表示启动正常

在mon上启动mmm_mon

#mmmd_mon
MySQL Multi-Master Replication Manager
Version: 1.2.6
Reading config file: 'mmm_mon.conf'
$VAR1 = {};

在管理节点上（mon）启动db节点：

#mmm_control set_online db1

MySQL Multi-Master Replication Manager
Version: 1.2.6
Config file: mmm_mon.conf
Daemon is running!
Command sent to monitoring host. Result: OK: State of 'db1' changed to ONLINE. Now you can wait some time and check its new roles!

#mmm_control set_online db2

MySQL Multi-Master Replication Manager
Version: 1.2.6
Config file: mmm_mon.conf
Daemon is running!
Command sent to monitoring host. Result: OK: State of 'db2' changed to ONLINE. Now you can wait some time and check its new roles!

查看下节点状态：

#mmm_control show

MySQL Multi-Master Replication Manager
Version: 1.2.6
Config file: mmm_mon.conf
Daemon is running!
===============================
Cluster failover method: AUTO
===============================
Servers status:
db1(10.10.1.65): master/ONLINE. Roles: reader(10.10.1.78;), writer(10.10.1.79;)
db2(10.10.1.58): master/ONLINE. Roles: reader(10.10.1.77;)

看到这个就说明配置没有问题,现在我们来进行切换测试,看切换是否正常,我现在把node1的mysql停止掉然后在看下节点的状态

#mmm_control show

[root@localhost etc]# mmm_control show
MySQL Multi-Master Replication Manager
Version: 1.2.6
Config file: mmm_mon.conf
Daemon is running!
===============================
Cluster failover method: AUTO
===============================
Servers status:
db1(10.10.1.65): master/HARD_OFFLINE. Roles: None
db2(10.10.1.58): master/ONLINE. Roles: reader(10.10.1.77;), reader(10.10.1.78;), writer(10.10.1.79;)

可以看到读写操作都转到了node2机器上了,看来切换没有问题,测试了下,切换需要大概3秒的时间,还算是可以接受的了.