参考资料： http://www.clusterdb.com/mysql/replication-and-auto-failover-made-easy-with-mysql-utilities 环境介绍: master: demoenv-trial-1 slaves: demoenv-trial-2 demoenv-trial-3 1. 安装 Percona Server，在所有服务器上： $ sudo yum install ht
参考资料：
http://www.clusterdb.com/mysql/replication-and-auto-failover-made-easy-with-mysql-utilities
环境介绍:
master: demoenv-trial-1
slaves: demoenv-trial-2 demoenv-trial-3
1. 安装 Percona Server，在所有服务器上：
$ sudo yum install http://www.percona.com/downloads/percona-release/percona-release-0.0-1.x86_64.rpm
$ sudo yum install Percona-Server-shared-compat
$ sudo yum install Percona-Server-server-56
$ sudo yum install http://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm
$ sudo yum install mysql-utilities
2. 配置 /etc/my.cnf，在所有服务器上：
注意：确保 server-id 不同且 report-host 与自身主机名相同
$ sudo vim /etc/my.cnf
[mysqld] # basic setting datadir = /opt/mysql/data tmpdir = /opt/mysql/tmp socket = /opt/mysql/run/mysqld.sock port = 3306 pid-file = /opt/mysql/run/mysqld.pid # innodb setting default-storage-engine = INNODB innodb_file_per_table = 1 log-bin = /opt/mysql/binlogs/bin-log-mysqld log-bin-index = /opt/mysql/binlogs/bin-log-mysqld.index innodb_data_home_dir = /opt/mysql/data innodb_data_file_path = ibdata1:10M:autoextend innodb_log_group_home_dir = /opt/mysql/data binlog-do-db = testdb # server id server-id=1 # gtids setting binlog-format = ROW log-slave-updates = true gtid-mode = on enforce-gtid-consistency = true report-host = demoenv-trial-1 report-port = 3306 master-info-repository = TABLE relay-log-info-repository = TABLE sync-master-info = 1 # other settings [mysqld_safe] log-error = /opt/mysql/log/mysqld.log pid-file = /opt/mysql/run/mysqld.pid open-files-limit = 8192 [mysqlhotcopy] interactive-timeout [client] port = 3306 socket = /opt/mysql/run/mysqld.sock default-character-set = utf8
3. 创建所需目录，在所有服务器上：
$ sudo mkdir -p /opt/mysql/{data,tmp,run,binlogs,log}
$ sudo chown mysql:mysql /opt/mysql/{data,tmp,run,binlogs,log}
4. 初始化数据库，在所有服务器上：
$ sudo -i
# su - mysql
$ mysql_install_db --user=mysql --datadir=/opt/mysql/data/
$ exit
# exit
$ sudo /etc/init.d/mysql start
5. 创建授权用户 root@'%' 以便通过 mysqlreplicate 来进行主从复制的配置，在所有服务器上：
$ mysql -uroot
mysql> grant all on *.* to root@'%' identified by 'pass' with grant option; mysql> quit;
6. 创建复制所需的用户，在所有服务器上：
$ mysql -uroot
mysql> grant replication slave on *.* to 'rpl'@'%' identified by 'rpl'; mysql> quit;
7. 配置主从复制，可选择任意一台服务器操作：
[dong.guo@demoenv-trial-1 ~]$ mysql -uroot
mysql> use mysql; mysql> drop user root@'demoenv-trial-1'; mysql> quit;
[dong.guo@demoenv-trial-1 ~]$ mysqlreplicate --master=root:pass@'demoenv-trial-1':3306 --slave=root:pass@'demoenv-trial-2':3306 --rpl-user=rpl:rpl
# master on demoenv-trial-1: ... connected. # slave on demoenv-trial-2: ... connected. # Checking for binary logging on master... # set up replication... # ...done.
[dong.guo@demoenv-trial-1 ~]$ mysqlreplicate --master=root:pass@'demoenv-trial-1':3306 --slave=root:pass@'demoenv-trial-3':3306 --rpl-user=rpl:rpl
# master on demoenv-trial-1: ... connected. # slave on demoenv-trial-3: ... connected. # Checking for binary logging on master... # set up replication... # ...done.
8. 验证主从复制的数据完整性
[dong.guo@demoenv-trial-1 ~]$ mysql -uroot
mysql> create database testdb; mysql> quit;
[dong.guo@demoenv-trial-1 ~]$ mysql -uroot -ppass -h'demoenv-trial-2' -e 'show databases;'
+-------------------+ | Database | +-------------------+ | information_schema| | mysql | | performance_schema| | test | | testdb | +-------------------+
[dong.guo@demoenv-trial-1 ~]$ mysql -uroot -ppass -h'demoenv-trial-3' -e 'show databases;'
+-------------------+ | Database | +-------------------+ | information_schema| | mysql | | performance_schema| | test | | testdb | +-------------------+
[dong.guo@demoenv-trial-1 ~]$ mysqlrplshow --master=rpl:rpl@'demoenv-trial-1':3306 --discover-slaves-login=root:pass;
# master on demoenv-trial-1: ... connected. # Finding slaves for master: demoenv-trial-1:3306 # Replication Topology Graph demoenv-trial-1:3306 (MASTER) | +--- demoenv-trial-2:3306 - (SLAVE) | +--- demoenv-trial-3:3306 - (SLAVE)
[dong.guo@demoenv-trial-1 ~]$ mysqlrplcheck --master=root:pass@'demoenv-trial-1' --slave=root:pass@'demoenv-trial-2'
# master on demoenv-trial-1: ... connected. # slave on demoenv-trial-2: ... connected. Test Description Status --------------------- Checking for binary logging on master [pass] Are there binlog exceptions? [WARN] +--------+--------+-----------+ | server | do_db | ignore_db | +--------+--------+-----------+ | master | testdb | | +--------+--------+-----------+ Replication user exists? [pass] Checking server_id values [pass] Checking server_uuid values [pass] Is slave connected to master? [pass] Check master information file [pass] Checking InnoDB compatibility [pass] Checking storage engines compatibility [pass] Checking lower_case_table_names setting [pass] Checking slave delay (seconds behind master) [pass] # ...done.
9. 关闭 master 测试 auto-failover
[dong.guo@demoenv-trial-1 ~]$ mysqlfailover --master=root:pass@'demoenv-trial-1':3306 --discover-slaves-login=root:pass --rediscover
# Discovering slaves for master at demoenv-trial-1:3306 # Discovering slave at demoenv-trial-2:3306 # Found slave: demoenv-trial-2:3306 # Discovering slave at demoenv-trial-3:3306 # Found slave: demoenv-trial-3:3306 # Checking privileges. # Discovering slaves for master at demoenv-trial-1:3306 MySQL Replication Failover Utility Failover Mode = auto Next Interval = Sun Oct 20 06:58:52 2013 Master Information ------------------ Binary Log File Position Binlog_Do_DB Binlog_Ignore_DB bin-log-mysqld.00000 299 testdb GTID Executed Set 92df196b-3906-11e3-b6b6-000c290d14d7:1 Replication Health Status +-----------------+------+--------+-------+-----------+---------------+ | host | port | role | state | gtid_mode | health | +-----------------+------+--------+-------+-----------+---------------+ | demoenv-trial-1 | 3306 | MASTER | UP | ON | OK | | demoenv-trial-2 | 3306 | SLAVE | UP | ON | OK | | demoenv-trial-3 | 3306 | SLAVE | UP | ON | OK | +-----------------+------+--------+-------+-----------+---------------+ Q-quit R-refresh H-health G-GTID Lists U-UUIDs
然后，执行命令的终端就挂起了，需要另外开启一个终端来关闭master：
[dong.guo@demoenv-trial-1 ~]$ mysqladmin -uroot -ppass shutdown
接着，在刚刚挂起的终端上，可以看到：
Failover starting in 'auto' mode... # Candidate slave demoenv-trial-2:3306 will become the new master. # Checking slaves status (before failover). # Preparing candidate for failover. # Creating replication user if it does not exist. # Stopping slaves. # Performing STOP on all slaves. # Switching slaves to new master. # Disconnecting new master as slave. # Starting slaves. # Performing START on all slaves. # Checking slaves for errors. # Failover complete. # Discovering slaves for master at demoenv-trial-2:3306 Failover console will restart in 5 seconds. MySQL Replication Failover Utility Failover Mode = auto Next Interval = Sun Oct 20 07:01:25 2013 Master Information ------------------ Binary Log File Position Binlog_Do_DB Binlog_Ignore_DB bin-log-mysqld.00000 299 testdb GTID Executed Set 92df196b-3906-11e3-b6b6-000c290d14d7:1 Replication Health Status +-----------------+------+--------+-------+-----------+---------------+ | host | port | role | state | gtid_mode | health | +-----------------+------+--------+-------+-----------+---------------+ | demoenv-trial-2 | 3306 | MASTER | UP | ON | OK | | demoenv-trial-3 | 3306 | SLAVE | UP | ON | OK | +-----------------+------+--------+-------+-----------+---------------+ Q-quit R-refresh H-health G-GTID Lists U-UUIDs
服务器 'demoenv-trial-2' 变成了新的master。
10. 插入数据测试主从复制
[dong.guo@demoenv-trial-2 ~]$ mysql -uroot
mysql> use testdb;
Database changed
mysql> CREATE TABLE `hostgroup` (
-> `hostgroup_id` tinyint(4) NOT NULL AUTO_INCREMENT,
-> `hostgroup_name` char(20) DEFAULT NULL,
-> `hostgroup_next` tinyint(4) NOT NULL,
-> `colo_name` char(4) NOT NULL,
-> PRIMARY KEY (`hostgroup_id`)
-> ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
Query OK, 0 rows affected (0.10 sec)
mysql> quit;
[dong.guo@demoenv-trial-2 binlogs]$ mysql -uroot -ppass -h'demoenv-trial-3' testdb -e 'show tables;'
+-----------------+ | Tables_in_testdb| +-----------------+ | hostgroup | +-----------------+
11. 尝试将旧的master恢复
[dong.guo@demoenv-trial-1 ~]$ sudo /etc/init.d/mysql start
[dong.guo@demoenv-trial-1 ~]$ mysqlreplicate --master=root:pass@'demoenv-trial-2':3306 --slave=root:pass@'demoenv-trial-1':3306
# master on demoenv-trial-2: ... connected. # slave on demoenv-trial-1: ... connected. # Checking for binary logging on master... # setting up replication... # ...done.
在刚刚挂起的终端上，可以看到：
... Replication Health Status +-----------------+------+--------+-------+-----------+---------------+ | host | port | role | state | gtid_mode | health | +-----------------+------+--------+-------+-----------+---------------+ | demoenv-trial-2 | 3306 | MASTER | UP | ON | OK | | demoenv-trial-1 | 3306 | SLAVE | UP | ON | OK | | demoenv-trial-3 | 3306 | SLAVE | UP | ON | OK | +-----------------+------+--------+-------+-----------+---------------+ Q-quit R-refresh H-health G-GTID Lists U-UUIDs
将旧的master恢复
[dong.guo@demoenv-trial-1 ~]$ mysqlrpladmin --master=root:pass@'demoenv-trial-2':3306 --new-master=root:pass@'demoenv-trial-1':3306 --demote-master --discover-slaves-login=root:pass switchover
# Discovering slaves for master at demoenv-trial-2:3306 # Discovering slave at demoenv-trial-1:3306 # Found slave: demoenv-trial-1:3306 # Discovering slave at demoenv-trial-3:3306 # Found slave: demoenv-trial-3:3306 # Checking privileges. # Performing switchover from master at demoenv-trial-2:3306 to slave at demoenv-trial-1:3306. # Checking candidate slave prerequisites. # Checking slaves configuration to master. # Waiting for slaves to catch up to old master. # Stopping slaves. # Performing STOP on all slaves. # Demoting old master to be a slave to the new master. # Switching slaves to new master. # Starting all slaves. # Performing START on all slaves. # Checking slaves for errors. # Switchover complete. # # Replication Topology Health: +-----------------+------+--------+-------+-----------+---------------+ | host | port | role | state | gtid_mode | health | +-----------------+------+--------+-------+-----------+---------------+ | demoenv-trial-1 | 3306 | MASTER | UP | ON | OK | | demoenv-trial-2 | 3306 | SLAVE | UP | ON | OK | | demoenv-trial-3 | 3306 | SLAVE | UP | ON | OK | +-----------------+------+--------+-------+-----------+---------------+ # ...done.
在刚刚挂起的终端上，可以看到：
MySQL Replication Failover Utility Failover Mode = auto Next Interval = Sun Oct 20 07:30:07 2013 Master Information ------------------ Binary Log File Position Binlog_Do_DB Binlog_Ignore_DB bin-log-mysqld.00000 710 testdb GTID Executed Set 8a58172b-1efd-11e3-8cf1-000c2950fe0c:1 [...] Replication Health Status +-----------------+------+--------+-------+-----------+----------------------------------+ | host | port | role | state | gtid_mode | health | +-----------------+------+--------+-------+-----------+----------------------------------+ | demoenv-trial-2 | 3306 | MASTER | UP | ON | OK | | demoenv-trial-1 | 3306 | SLAVE | UP | WARN | Slave is not connected to master.| | demoenv-trial-3 | 3306 | SLAVE | UP | WARN | Slave is not connected to master.| +-----------------+------+--------+-------+-----------+----------------------------------+ Q-quit R-refresh H-health G-GTID Lists U-UUIDs
可以看到failover在手动恢复了旧的master之后已经停止了工作。
按下Q，然后重启auto-failover：
[dong.guo@demoenv-trial-1 ~]$ mysqlfailover --master=root:pass@'demoenv-trial-1':3306 --discover-slaves-login=root:pass --rediscover
... Replication Health Status +-----------------+------+--------+-------+-----------+---------------+ | host | port | role | state | gtid_mode | health | +-----------------+------+--------+-------+-----------+---------------+ | demoenv-trial-1 | 3306 | MASTER | UP | ON | OK | | demoenv-trial-2 | 3306 | SLAVE | UP | ON | OK | | demoenv-trial-3 | 3306 | SLAVE | UP | ON | OK | +-----------------+------+--------+-------+-----------+---------------+ Q-quit R-refresh H-health G-GTID Lists U-UUIDs
它又可以工作了。
12. 对于 auto-failover 的简短总结：
它包含在mysql-utilities这个软件包中；
它只能工作在MySQL 5.6 版本上，因为需要GITDs的支持；
它可以自动选取一个slave作为新的master，当现有的master死掉以后；
但是它不能自动将旧的master恢复，并且在手动恢复了旧的master之后也会停止工作。
原文地址：MySQL 官方 Auto-Failover 功能测试, 感谢原作者分享。
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