MySQL Auto-Failover 功能测试

╰半橙微兮° 2022-01-16 23:21 202阅读 0赞

[为什么80%的码农都做不了架构师？>>> ][80_]  ![hot3.png][]

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

**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：

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。 转自http://heylinux.com/archives/2776.html

转载于:https://my.oschina.net/766/blog/211243

[80_]: https://my.oschina.net/u/2663968/blog/3051541
[hot3.png]: /images/20220117/b442c1ca09b3476fbc5ac98a75718a6b.png