mysql-mmm高可用架構

出處http://navyaijm.blog.51cto.com/4647068/1230674

一、說明

1、本文將介紹如何使用mysql-mmm搭建數據庫的高可用架構，MMM即Master-Master Replication Manager for MySQL（mysql主主複製管理器）關於mysql主主複製配置的監控、故障轉移和管理的一套可伸縮的腳本套件（在任何時候只有一個節點可以被寫入），這個套件也能對居於標準的主從配置的任意數量的從服務器進行讀負載均衡，所以你可以用它來在一組居於複製的服務器啓動虛擬ip，除此之外，它還有實現數據備份、節點之間重新同步功能的腳本。MySQL本身沒有提供replication failover的解決方案，通過MMM方案能實現服務器的故障轉移，從而實現mysql的高可用。MMM不僅能提供浮動IP的功能，更可貴的是如果當前的主服務器掛掉後，會將你後端的從服務器自動轉向新的主服務器進行同步複製，不用手工更改同步配置。這個方案是目前比較成熟的解決方案（上面這段話從網上載錄）。至於mmm的具體介紹我這裏就不多講了，詳情請看官網：http://mysql-mmm.org。

2、該方案的優缺點：

優點：穩定性高，可擴展性好，高可用，當主服務器掛掉以後，另一個主立即接管，其他的從服務器能自動切換，不用人工干預。

缺點：monitor節點是單點，不過這個你也可以結合keepalived或者haertbeat做成高可用

二、環境

1、服務器列表

服務器	主機名	IP	serverID	mysql版本	系統
master1	db1	172.28.26.101	101	mysql5.5.15	Centos 6.4
master2	db2	172.28.26.102	102	mysql5.5.15	Centos 6.4
slave1	db3	172.28.26.188	188	mysql5.5.15	Centos 6.4
slave2	db4	172.28.26.189	189	mysql5.5.15	Centos 6.4
monitor	monitor	172.28.26.103	無		Centos 6.4

2、虛擬IP列表

VIP	Role	description
172.28.26.104	write	應用配置的寫入VIP
172.28.26.105	read	應用配置的讀入VIP
172.28.26.106	read	應用配置的讀入VIP

三、mysql的安裝

1、只在master1上安裝即可，其他機器scp過去就好，最好用rsync

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tar-zxvf mysql-5.5.15.tar.gz cdmysql-5.5.15 cmake -DCMAKE_INSTALL_PREFIX:PATH=/data/mysql/navy1-DMYSQL_DATADIR=/data/mysql/navy1/db-DMYSQL_TCP_PORT=3306 -DMYSQL_UNIX_ADDR=/tmp/mysql.sock -DDEFAULT_CHARSET=utf8 -DDEFAULT_COLLATION=utf8_general_ci -DWITH_MYISAM_STORAGE_ENGINE=1 -DWITH_INNOBASE_STORAGE_ENGINE=1 -DWITH_READLINE=1 -DENABLED_LOCAL_INFILE=1 make makeinstall useraddmysql -s /sbin/nologin; cd/data/mysql/navy1; chownmysql:mysql db/ logs/ -R

vi /data/mysql/navy1/my.cnf (cp一份線上的配置文件修改一下)

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[mysqld_safe] log-error=/data/mysql/navy1/logs/mysqld.log pid-file=/data/mysql/navy1/logs/mysqld.pid [client] port            = 3306 socket          = /data/mysql/navy1/logs/mysql.sock [mysqld] port            = 3306 socket          = /data/mysql/navy1/logs/mysql.sock key_buffer = 384M max_allowed_packet = 1M table_cache = 512 sort_buffer_size = 2M read_buffer_size = 2M read_rnd_buffer_size = 8M myisam_sort_buffer_size = 64M thread_cache_size = 8 query_cache_size = 64M basedir=/data/mysql/navy1 datadir=/data/mysql/navy1/db thread_concurrency = 8 log-bin=mysql-bin binlog_format = mixed server-id= 101 max_connections=2048 character_set_server=utf8 wait_timeout=1800 interactive_timeout=1800 skip-show-database skip-name-resolve tmp_table_size = 512M max_heap_table_size = 512M binlog-ignore-db = mysql replicate-ignore-db = mysql binlog-ignore-db = information_schema replicate-ignore-db = information_schema binlog-ignore-db = performance_schema replicate-ignore-db = performance_schema binlog-ignore-db = test replicate-ignore-db = test innodb_data_home_dir = /data/mysql/navy1/db #innodb_data_file_path = ibdata1:4000M;ibdata2:10M:autoextend innodb_file_per_table=1 innodb_log_group_home_dir = /data/mysql/navy1/db innodb_buffer_pool_size = 2000M innodb_additional_mem_pool_size = 20M innodb_log_file_size = 100M innodb_log_buffer_size = 8M innodb_flush_log_at_trx_commit = 2 innodb_lock_wait_timeout = 50 #default-storage-engine = MyISAM default-storage-engine = InnoDB [mysqldump] quick max_allowed_packet = 16M [mysql] no-auto-rehash [isamchk] key_buffer = 256M sort_buffer_size = 256M read_buffer = 2M write_buffer = 2M [myisamchk] key_buffer = 256M sort_buffer_size = 256M read_buffer = 2M write_buffer = 2M [mysqlhotcopy] interactive-timeout

初始化數據庫：

1	/data/mysql/navy1/scripts/mysql_install_db--user=mysql --basedir=/data/mysql/navy1--datadir=/data/mysql/navy1/db/

啓動數據庫：

1	cd/data/mysql/navy1; /data/mysql/navy1/bin/mysqld_safe--defaults-extra-file=/data/mysql/navy1/my.cnf --user=mysql &

2、其他三天機器的mysql的安裝僅需四步：

A、把已經安裝好的master上的mysql停掉，rsync到master2、和兩臺slave的對應目錄下（/data/mysql/navy1）

B、建用戶、改權限

1	useraddmysql -s /sbin/nologin; cd/data/mysql/navy1; chownmysql:mysql db/ logs/ -R

C、修改/data/mysql/navy1/my.cnf中的serverID

D、啓動數據庫：

1	cd/data/mysql/navy1; /data/mysql/navy1/bin/mysqld_safe--defaults-extra-file=/data/mysql/navy1/my.cnf --user=mysql &

四、主從配置（master1和master2配置成主主，slave1和slave2配置成master1的從）：

1、在master1上授權：

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grant replication slave on *.* to slave@'172.28.26.102'identified by "123456"; grant replication slave on *.* to slave@'172.28.26.188'identified by "123456"; grant replication slave on *.* to slave@'172.28.26.189'identified by "123456";

2、在master2上授權：

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grant replication slave on *.* to slave@'172.28.26.101'identified by "123456"; grant replication slave on *.* to slave@'172.28.26.188'identified by "123456"; grant replication slave on *.* to slave@'172.28.26.189'identified by "123456";

3、把master2、slave1和slave2配置成master1的從庫：

A、在master1上執行show master status \G 獲取binlog文件和Position點

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mysql> show master status \G ERROR 2006 (HY000): MySQL server has gone away No connection. Trying to reconnect... Connection id:    3974 Current database: *** NONE *** *************************** 1. row *************************** File: mysql-bin.000024 Position: 107 Binlog_Do_DB: Binlog_Ignore_DB: mysql,information_schema,performance_schema,test,mysql,information_schema,performance_schema,test 1 row inset(0.00 sec)

B、在master2、slave1和slave2執行

1 2	change master to master_host='172.28.26.101', master_Port=3306, master_user='slave', master_password='123456', master_log_file='mysql-bin.000024', master_log_pos=107; slave start;

4、把master1配置成master2的從庫:

A、在master2上執行show master status \G 獲取binlog文件和Position點

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mysql>  show master status \G *************************** 1. row *************************** File: mysql-bin.000025 Position: 107 Binlog_Do_DB: navy Binlog_Ignore_DB: mysql,mysql,information_schema,performance_schema,test,mysql,information_schema,performance_schema,test 1 row inset(0.00 sec)

B、在master1上執行：

1 2	change master to master_host='172.28.26.101', master_Port=3306, master_user='slave', master_password='123456', master_log_file='mysql-bin.000025', master_log_pos=107; slave start;

5、在各個機器上執行：

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mysql> show slave status \G *************************** 1. row *************************** Slave_IO_State: Waiting formaster to send event Master_Host: 172.28.26.102 Master_User: slave Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000025 Read_Master_Log_Pos: 107 Relay_Log_File: mysqld-relay-bin.000015 Relay_Log_Pos: 253 Relay_Master_Log_File: mysql-bin.000025 Slave_IO_Running: Yes Slave_SQL_Running: Yes

如果Slave_IO_Running和Slave_SQL_Running都爲yes，那麼主從就已經配置OK了

五、mysql-mmm安裝

1、db節點：

1	yum -y installmysql-mmm-agent

2、monitor節點：

1	yum -y installmysql-mmm*

六、mysql-mmm的配置：

1、在4個db節點授權：

1 2	GRANT SUPER, REPLICATION CLIENT, PROCESS ON *.* TO 'mmm_agent'@'172.28.26.%'IDENTIFIED BY'123456'; GRANT REPLICATION CLIENT ON *.* TO 'mmm_monitor'@'172.28.26.%'IDENTIFIED BY '123456';

2、修改配置文件

vi /etc/mysql-mmm/mmm_common.conf （db、monitor一樣樣的）

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active_master_role      writer <host default> cluster_interface       eth1 pid_path                /var/run/mysql-mmm/mmm_agentd.pid bin_path                /usr/libexec/mysql-mmm/ replication_user        slave replication_password    123456 agent_user              mmm_agent agent_password          123456 </host> <host db1> ip      172.28.26.101 mysql_port              3306 mode    master peer    db2 </host> <host db2> ip      172.28.26.102 mysql_port              3306 mode    master peer    db1 </host> <host db3> ip      172.28.26.188 mysql_port              3306 mode    slave peer    db3 </host> <host db4> ip      172.28.26.189 mysql_port              3306 mode    slave peer    db4 </host> <role writer> hosts   db1, db2 ips     172.28.26.104 mode    exclusive </role> <role reader> hosts   db3, db4 ips     172.28.26.105,172.28.26.106 mode    balanced </role>

PS：

peer的意思是等同，表示db1與db2是同等的。

ips指定VIP

mode exclusive 只有兩種模式：exclusive是排他，在這種模式下任何時候只能一個host擁有該角色

balanced模式下可以多個host同時擁有此角色。一般writer是exclusive，reader是balanced

vi /etc/mysql-mmm/mmm_agent.conf （master1、master2、slave1和slave2分別修改爲：this db1、db2、db3、db4）

vi /etc/mysql-mmm/mmm_mon.conf（僅monitor節點有）

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include mmm_common.conf <monitor> ip                  127.0.0.1 pid_path            /var/run/mysql-mmm/mmm_mond.pid bin_path            /usr/libexec/mysql-mmm status_path         /var/lib/mysql-mmm/mmm_mond.status ping_ips            172.28.26.101,172.28.26.102 auto_set_online     10 # The kill_host_bin does not exist by default, though the monitor will # throw a warning about it missing.  See the section 5.10 "Kill Host # Functionality" in the PDF documentation. # # kill_host_bin     /usr/libexec/mysql-mmm/monitor/kill_host # </monitor> <host default> monitor_user        mmm_monitor monitor_password    123456 </host> debug 0

七、mmm啓動

1、db節點：

1 2	/etc/init.d/mysql-mmm-agentstart echo"/etc/init.d/mysql-mmm-agent start">> /etc/rc.local

2、 monitor節點：

八、測試

1、集羣正常啓動：

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[root@monitor ~]# mmm_control show db1(172.28.26.101) master/ONLINE. Roles: writer(172.28.26.104) db2(172.28.26.102) master/ONLINE. Roles: db3(172.28.26.188) slave/ONLINE. Roles: reader(172.28.26.106) db4(172.28.26.189) slave/ONLINE. Roles: reader(172.28.26.105)

2、停掉db1，看172.28.26.104是否漂移到db2上，db3、db4的主是否切換到db2

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[root@monitor ~]# mmm_control show db1(172.28.26.101) master/HARD_OFFLINE. Roles: db2(172.28.26.102) master/ONLINE. Roles: writer(172.28.26.104) db3(172.28.26.188) slave/ONLINE. Roles: reader(172.28.26.106) db4(172.28.26.189) slave/ONLINE. Roles: reader(172.28.26.105)

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mysql> show slave status \G Connection id:    5844 Current database: *** NONE *** *************************** 1. row *************************** Slave_IO_State: Waiting formaster to send event Master_Host: 172.28.26.102 Master_User: slave Master_Port: 3306 Connect_Retry: 60 Master_Log_File: mysql-bin.000025 Read_Master_Log_Pos: 107 Relay_Log_File: mysqld-relay-bin.000002 Relay_Log_Pos: 253 Relay_Master_Log_File: mysql-bin.000025 Slave_IO_Running: Yes Slave_SQL_Running: Yes Replicate_Do_DB: