MySQL Group Replication 搭建[Single-Primary Mode]

快来打我* 2022-07-13 02:59 150阅读 0赞

这篇文章记录如何部署mysql group replication 单写模式 (single-primary mode)

> 部署方式大致与多写模式的部署一致，所需要修改的只有my.cnf里面关于group replication的配置。

多写模式的部署参考另外一篇文章:

[http://blog.csdn.net/d6619309/article/details/53691790][http_blog.csdn.net_d6619309_article_details_53691790]

# 1. 环境准备 #

*  CentOS5.6
 *  mysql-5.7.17-linux-glibc2.5-x86\_64.tar.gz

# 2. 部署 #

我们的目标是在一台机器上安装3个mysql实例，然后配置mysql group replication，模式为single-primary mode

安装目录说明如下:

1) 实例数据将安装在

*  s1: `/dba/mysql/data/s1`
 *  s2: `/dba/mysql/data/s2`
 *  s3: `/dba/mysql/data/s3`

2) mysql5.7解压到

/dba/mysql/mysql-5.7

## 2.1 安装多实例(s1、s2、s3) ##

出于试验和测试的考虑，我们直接用编译好的mysql安装包进行精简安装:

cd /dba/mysql
    mkdir data
    mysql-5.7/bin/mysqld --initialize-insecure --basedir=$PWD/mysql-5.7 --datadir=$PWD/data/s1
    mysql-5.7/bin/mysqld --initialize-insecure --basedir=$PWD/mysql-5.7 --datadir=$PWD/data/s2
    mysql-5.7/bin/mysqld --initialize-insecure --basedir=$PWD/mysql-5.7 --datadir=$PWD/data/s3

## 2.2 s1实例部署 ##

### 2.2.1 配置实例 ###

cd $PWD/data/s1
    touch s1.cnf
    vi s1.cnf

*  加入主配置

[mysqld]
    
    # server configuration
    datadir=/dba/mysql/data/s1
    basedir=/dba/mysql/mysql-5.7/
    
    port=24801
    socket=/dba/mysql/data/s1/s1.sock

*  加入replication配置

server_id=1
    gtid_mode=ON
    enforce_gtid_consistency=ON
    master_info_repository=TABLE
    relay_log_info_repository=TABLE
    binlog_checksum=NONE
    log_slave_updates=ON
    log_bin=binlog
    binlog_format=ROW

其中大部分配置是为了打开group replication必须配置的，详见:

[http://mysqlhighavailability.com/mysqlha/gr/doc/limitations.html][http_mysqlhighavailability.com_mysqlha_gr_doc_limitations.html]

*  加入group replication配置

transaction_write_set_extraction=XXHASH64
    loose-group_replication_group_name="aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"
    loose-group_replication_start_on_boot=off
    loose-group_replication_local_address= "127.0.0.1:24901"
    loose-group_replication_group_seeds= "127.0.0.1:24901,127.0.0.1:24902,127.0.0.1:24903"
    loose-group_replication_bootstrap_group= off
    loose-group_replication_single_primary_mode=true
    loose-group_replication_enforce_update_everywhere_checks=false

配置解释见:

[http://mysqlhighavailability.com/mysqlha/gr/doc/getting\_started.html\#group-replication][http_mysqlhighavailability.com_mysqlha_gr_doc_getting_started.html_group-replication]

注意关闭多写模式相关配置:

*  `loose-group_replication_single_primary_mode=true`
 *  `loose-group_replication_enforce_update_everywhere_checks=false`

### 2.2.2 启动实例 ###

执行以下命令启动s1实例:

nohup mysql-5.7/bin/mysqld --defaults-file=data/s1/s1.cnf >data/s1/nohup.out 2>data/s1/nohup.out &

> 注意mysql用户必须拥有对data目录下的读写权限

### 2.2.3 用户授权 ###

成功启动之后，登陆mysql:

mysql -uroot -h127.0.0.1 -P24801 --skip-password

登陆之后建议修改root登陆密码，通过以下语句修改:

SET SQL_LOG_BIN=0;
    ALTER USER 'root'@'localhost' IDENTIFIED BY 'mysql';
    SET SQL_LOG_BIN=1;

--------------------

修改密码遇到ERROR：

ERROR 1819 (HY000): Your password does not satisfy the current policy requirements

密码安全策略太高引起，参考[http://www.cnblogs.com/ivictor/p/5142809.html][http_www.cnblogs.com_ivictor_p_5142809.html]

执行：

set global validate_password_policy=0;

然后再设置密码即可

--------------------

mysql命令行下创建group replication所需要的用户:

SET SQL_LOG_BIN=0;
    CREATE USER rpl_user@'%';
    GRANT REPLICATION SLAVE ON *.* TO rpl_user@'%' IDENTIFIED BY 'rpl_pass';
    FLUSH PRIVILEGES;
    SET SQL_LOG_BIN=1;
    CHANGE MASTER TO MASTER_USER='rpl_user', MASTER_PASSWORD='rpl_pass' FOR CHANNEL 'group_replication_recovery';

### 2.2.4 开启组复制 ###

mysql命令行下执行:

mysql> INSTALL PLUGIN group_replication SONAME 'group_replication.so';

看到group\_replication确保安装插件成功

接下来执行下面的语句，启动group replication:

SET GLOBAL group_replication_bootstrap_group=ON;
    START GROUP_REPLICATION;
    SET GLOBAL group_replication_bootstrap_group=OFF;

执行下面的语句，验证group replication已经成功启动:

接下来创建测试用的库和表:

mysql> CREATE DATABASE test;
    Query OK, 1 row affected (0,00 sec)
    
    mysql> use test
    Database changed
    mysql> CREATE TABLE t1 (c1 INT PRIMARY KEY, c2 TEXT NOT NULL);
    Query OK, 0 rows affected (0,00 sec)
    
    mysql> INSERT INTO t1 VALUES (1, 'Luis');
    Query OK, 1 row affected (0,01 sec)
    
    mysql> SELECT * FROM t1;
    +----+------+
    | c1 | c2   |
    +----+------+
    |  1 | Luis |
    +----+------+
    1 row in set (0,00 sec) mysql> show binlog events;
    +---------------+------+----------------+-----------+-------------+----------------------------------------------------------------------------------------------------------------------+
    | Log_name      | Pos  | Event_type     | Server_id | End_log_pos | Info                                                                                                                 |
    +---------------+------+----------------+-----------+-------------+----------------------------------------------------------------------------------------------------------------------+
    | binlog.000001 |    4 | Format_desc    |         1 |         123 | Server ver: 5.7.17-log, Binlog ver: 4                                                                                |
    | binlog.000001 |  123 | Previous_gtids |         1 |         150 |                                                                                                                      |
    | binlog.000001 |  150 | Gtid           |         1 |         211 | SET @@SESSION.GTID_NEXT= '3c992270-c282-11e6-93bf-fa163ee40410:1' | | binlog.000001 | 211 | Query | 1 | 386 | ALTER USER 'root'@'localhost' IDENTIFIED WITH 'mysql_native_password' AS '*E74858DB86EBA20BC33D0AECAE8A8108C56B17FA' | | binlog.000001 | 386 | Gtid | 1 | 447 | SET @@SESSION.GTID_NEXT= 'aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa:1' | | binlog.000001 | 447 | Query | 1 | 506 | BEGIN | | binlog.000001 | 506 | View_change | 1 | 645 | view_id=14817781596395401:1 | | binlog.000001 | 645 | Query | 1 | 710 | COMMIT | | binlog.000001 | 710 | Gtid | 1 | 771 | SET @@SESSION.GTID_NEXT= 'aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa:2' | | binlog.000001 | 771 | Query | 1 | 861 | CREATE DATABASE test | | binlog.000001 | 861 | Gtid | 1 | 922 | SET @@SESSION.GTID_NEXT= 'aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa:3' | | binlog.000001 | 922 | Query | 1 | 1046 | use `test`; CREATE TABLE t1 (c1 INT PRIMARY KEY, c2 TEXT NOT NULL) | | binlog.000001 | 1046 | Gtid | 1 | 1107 | SET @@SESSION.GTID_NEXT= 'aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa:4' | | binlog.000001 | 1107 | Query | 1 | 1175 | BEGIN | | binlog.000001 | 1175 | Table_map | 1 | 1218 | table_id: 219 (test.t1) | | binlog.000001 | 1218 | Write_rows | 1 | 1260 | table_id: 219 flags: STMT_END_F | | binlog.000001 | 1260 | Xid | 1 | 1287 | COMMIT /* xid=47 */ | +---------------+------+----------------+-----------+-------------+----------------------------------------------------------------------------------------------------------------------+ 17 rows in set (0.00 sec)

## 2.3 增加新成员s2 ##

cd data/s2
    touch s2.cnf
    vi s2.cnf

与配置s1实例类似，增加s2.cnf并写入如下配置:

[mysqld]
    
    # server configuration
    datadir=/dba/mysql/data/s2
    basedir=/dba/mysql/mysql-5.7/
    
    port=24802
    socket=/dba/mysql/data/s2/s2.sock
    
    #
    # Replication configuration parameters
    #
    server_id=2
    gtid_mode=ON
    enforce_gtid_consistency=ON
    master_info_repository=TABLE
    relay_log_info_repository=TABLE
    binlog_checksum=NONE
    log_slave_updates=ON
    log_bin=binlog
    binlog_format=ROW
    
    #
    # Group Replication configuration
    #
    transaction_write_set_extraction=XXHASH64
    loose-group_replication_group_name="aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"
    loose-group_replication_start_on_boot=off
    loose-group_replication_local_address= "127.0.0.1:24902"
    loose-group_replication_group_seeds= "127.0.0.1:24901,127.0.0.1:24902,127.0.0.1:24903"
    loose-group_replication_bootstrap_group= off
    loose-group_replication_single_primary_mode=true
    loose-group_replication_enforce_update_everywhere_checks=false

之后启动s2实例:

nohup mysql-5.7/bin/mysqld --defaults-file=data/s2/s2.cnf >data/s2/nohup.out 2>data/s2/nohup.out &

修改用户密码:

SET SQL_LOG_BIN=0;
    ALTER USER 'root'@'localhost' IDENTIFIED BY 'mysql';
    SET SQL_LOG_BIN=1;

之后配置group replication需要的用户:

接下来安装group replication插件:

mysql> INSTALL PLUGIN group_replication SONAME 'group_replication.so';

然后就可以把s2添加到当前group里面:

mysql> START GROUP_REPLICATION;

**【注意】** 前面的用户密码修改和创建用户操作必须设置binlog不记录，执行后再打开，否则会引起`START GROUP_REPLICATION`执行报错:

报错信息如下所示:

ERROR 3092 (HY000): The server is not configured properly to be an active member of the group. Please see more details on error log.

mysql后台报错信息:

2016-12-15T07:51:28.317816Z 0 [ERROR] Plugin group_replication reported: 'This member has more executed transactions than those present in the group. Local transactions: f16f7f74-c283-11e6-ae37-fa163ee40410:1 > Group transactions: 3c992270-c282-11e6-93bf-fa163ee40410:1,
    aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa:1-5'
    2016-12-15T07:51:28.317878Z 0 [ERROR] Plugin group_replication reported: 'The member contains transactions not present in the group. The member will now exit the group.'
    2016-12-15T07:51:28.317887Z 0 [Note] Plugin group_replication reported: 'To force this member into the group you can use the group_replication_allow_local_disjoint_gtids_join option'
    2016-12-15T07:51:28.317999Z 14 [Note] Plugin group_replication reported: 'Going to wait for view modification'
    2016-12-15T07:51:28.318429Z 0 [Note] Plugin group_replication reported: 'getstart group_id 4317e324'
    2016-12-15T07:51:32.437462Z 0 [Note] Plugin group_replication reported: 'state 4330 action xa_terminate'
    2016-12-15T07:51:32.437897Z 0 [Note] Plugin group_replication reported: 'new state x_start'
    2016-12-15T07:51:32.437913Z 0 [Note] Plugin group_replication reported: 'state 4257 action xa_exit'
    2016-12-15T07:51:32.437981Z 0 [Note] Plugin group_replication reported: 'Exiting xcom thread'
    2016-12-15T07:51:32.437993Z 0 [Note] Plugin group_replication reported: 'new state x_start'
    2016-12-15T07:51:37.472364Z 14 [Note] Plugin group_replication reported: 'auto_increment_increment is reset to 1'
    2016-12-15T07:51:37.472474Z 14 [Note] Plugin group_replication reported: 'auto_increment_offset is reset to 1'
    2016-12-15T07:51:37.472943Z 19 [Note] Error reading relay log event for channel 'group_replication_applier': slave SQL thread was killed
    2016-12-15T07:51:37.485851Z 16 [Note] Plugin group_replication reported: 'The group replication applier thread was killed'

如果出现上述问题，**解决方案**是：根据提示打开`group_replication_allow_local_disjoint_gtids_join`选项，mysql命令行执行:

mysql> set global group_replication_allow_local_disjoint_gtids_join=ON;

然后再执行:

mysql> start group_replication;
    Query OK, 0 rows affected (7.89 sec)

执行成功，查询组成员信息:

看到实例s2已经加入当前group

查看database发现`test`数据库和表`t1`已经被同步创建:

表t1的数据也被同步了:

mysql> select * from t1;
    +----+------+
    | c1 | c2   |
    +----+------+
    |  1 | Luis |
    +----+------+
    1 row in set (0.00 sec

## 2.4 增加新实例s3 ##

与增加s2实例类似，不赘述，直接看配置:

cd data/s3
    touch s3.cnf
    vi s3.cnf

[mysqld]
    
    # server configuration
    datadir=/dba/mysql/data/s3
    basedir=/dba/mysql/mysql-5.7/
    
    port=24803
    socket=/dba/mysql/data/s3/s3.sock
    
    #
    # Replication configuration parameters
    #
    server_id=3
    gtid_mode=ON
    enforce_gtid_consistency=ON
    master_info_repository=TABLE
    relay_log_info_repository=TABLE
    binlog_checksum=NONE
    log_slave_updates=ON
    log_bin=binlog
    binlog_format=ROW
    
    #
    # Group Replication configuration
    #
    transaction_write_set_extraction=XXHASH64
    loose-group_replication_group_name="aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"
    loose-group_replication_start_on_boot=off
    loose-group_replication_local_address= "127.0.0.1:24903"
    loose-group_replication_group_seeds= "127.0.0.1:24901,127.0.0.1:24902,127.0.0.1:24903"
    loose-group_replication_bootstrap_group= off
    loose-group_replication_single_primary_mode=true
    loose-group_replication_enforce_update_everywhere_checks=false

启动s3实例:

nohup mysql-5.7/bin/mysqld --defaults-file=data/s3/s3.cnf >data/s3/nohup.out 2>data/s3/nohup.out &

登陆、修改密码后，执行:

SET SQL_LOG_BIN=0;
    ALTER USER 'root'@'localhost' IDENTIFIED BY 'mysql';
    SET SQL_LOG_BIN=1;

安装插件:

INSTALL PLUGIN group_replication SONAME 'group_replication.so';

最后将s3加入group:

START GROUP_REPLICATION;

查看同步状态:

mysql> SELECT * FROM performance_schema.replication_group_members;
    +---------------------------+--------------------------------------+-------------+-------------+--------------+
    | CHANNEL_NAME              | MEMBER_ID                            | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE |
    +---------------------------+--------------------------------------+-------------+-------------+--------------+
    | group_replication_applier | 3c992270-c282-11e6-93bf-fa163ee40410 | ${yourhost}  |       24801 | ONLINE       |
    | group_replication_applier | f16f7f74-c283-11e6-ae37-fa163ee40410 | ${yourhost}  |       24802 | ONLINE       |
    | group_replication_applier | f9b49bd8-c283-11e6-afb2-fa163ee40410 | ${yourhost}  |       24803 | ONLINE       |
    +---------------------------+--------------------------------------+-------------+-------------+--------------+
    3 rows in set (0.00 sec) mysql> show databases;
    +--------------------+
    | Database           |
    +--------------------+
    | information_schema |
    | mysql              |
    | performance_schema |
    | sys                |
    | test               |
    +--------------------+
    5 rows in set (0.00 sec) mysql> use test;
    Reading table information for completion of table and column names
    You can turn off this feature to get a quicker startup with -A
    
    Database changed
    mysql> show tables;
    +----------------+
    | Tables_in_test |
    +----------------+
    | t1             |
    +----------------+
    1 row in set (0.00 sec) mysql> select * from t1;
    +----+------+
    | c1 | c2   |
    +----+------+
    |  1 | Luis |
    +----+------+
    1 row in set (0.00 sec)

这个时候已经完成了一个group replication multi primary mode的部署了。

如何查看group内哪个节点是作为primary节点，官方提供了一个方法:

SELECT VARIABLE_VALUE FROM performance_schema.global_status WHERE VARIABLE_NAME= 'group_replication_primary_member';

得到的是primary节点的MEMBER\_ID，这个id等价于`server_uuid`

# 3. 简单测试 #

*  在s3上面执行:

mysql> insert into t1(c1, c2) values(null, 's3');
    ERROR 1290 (HY000): The MySQL server is running with the --super-read-only option so it cannot execute this statement

执行报错，single-primary mode下只有primary可以写(s1)。

*  在s2上面执行:

mysql> insert into t1(c1, c2) values(null, 's2');
    ERROR 1290 (HY000): The MySQL server is running with the --super-read-only option so it cannot execute this statement

同样报错。

*  在s1上面执行:

mysql> insert into t1(c1, c2) values(null, 's1');
    Query OK, 1 row affected (0.03 sec)

执行成功。

在s2和s3上查询数据同步情况:

mysql> select * from t1;
    +----+------+
    | c1 | c2   |
    +----+------+
    |  1 | Luis |
    |  8 | s1   |
    +----+------+
    2 rows in set (0.00 sec)

> group replication 自增列的步长默认为7

# 4. 参考 #

[http://dev.mysql.com/doc/refman/5.7/en/group-replication-getting-started.html][http_dev.mysql.com_doc_refman_5.7_en_group-replication-getting-started.html]

[http_blog.csdn.net_d6619309_article_details_53691790]: http://blog.csdn.net/d6619309/article/details/53691790
[http_mysqlhighavailability.com_mysqlha_gr_doc_limitations.html]: http://mysqlhighavailability.com/mysqlha/gr/doc/limitations.html
[http_mysqlhighavailability.com_mysqlha_gr_doc_getting_started.html_group-replication]: http://mysqlhighavailability.com/mysqlha/gr/doc/getting_started.html#group-replication
[http_www.cnblogs.com_ivictor_p_5142809.html]: http://www.cnblogs.com/ivictor/p/5142809.html
[http_dev.mysql.com_doc_refman_5.7_en_group-replication-getting-started.html]: http://dev.mysql.com/doc/refman/5.7/en/group-replication-getting-started.html