安装MGR 8.0

软件版本：
操作系统：CentOS 7.6
数据库：MySQL 8.0.19
虚拟机：VM Workstation 15 Pro

IP地址分配：
DB1 192.168.5.130:3306
DB2 192.168.5.130:3307
DB3 192.168.5.130:3308

1、安装MySQL

#依赖包
yum -y install libaio*

#解压软件
xz -d mysql-8.0.19-linux-glibc2.12-x86_64.tar.xz
tar -xvf mysql-8.0.19-linux-glibc2.12-x86_64.tar -C /usr/local
ln -s /usr/local/mysql-8.0.19-linux-glibc2.12-x86_64/ /usr/local/mysql

#创建用户
groupadd mysql
useradd -r -g mysql -s /bin/false mysql

#创建数据目录
mkdir -p /mysql_data/data/s{1..3}
chown mysql:mysql -R /mysql_data/data
chmod 750 -R /mysql_data/data

#初始化

/usr/local/mysql/bin/mysqld --initialize-insecure --basedir=/usr/local/mysql --datadir=/mysql_data/data/s1 --user=mysql
/usr/local/mysql/bin/mysqld --initialize-insecure --basedir=/usr/local/mysql --datadir=/mysql_data/data/s2 --user=mysql
/usr/local/mysql/bin/mysqld --initialize-insecure --basedir=/usr/local/mysql --datadir=/mysql_data/data/s3 --user=mysql

#my3306.cnf

#几乎默认参数，方便你们安装
[client]
#user = root
#password = xxxxx

[mysqld]
# basic settings #
user = mysql
port = 3306
socket = mysql.sock
basedir = /usr/local/mysql
datadir =  /mysql_data/data/s1
bind-address = 0.0.0.0
max_connections = 500
max_connect_errors = 1000
log_error = error.log
pid-file = mysql.pid
server-id = 3306130
log_bin = binlog
binlog_format = row
sync_binlog = 1
log_timestamps=SYSTEM
interactive_timeout = 28800
wait_timeout = 28800
default_authentication_plugin=mysql_native_password
transaction_isolation = READ-COMMITTED
binlog_rows_query_log_events = 1

# group repl settings #
gtid_mode=ON
enforce_gtid_consistency=ON
binlog_checksum=NONE

plugin_load_add='group_replication.so'
group_replication_group_name="aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"
group_replication_start_on_boot=off
group_replication_local_address= "192.168.5.130:33061"
group_replication_group_seeds= "192.168.5.130:33061,192.168.5.130:33062,192.168.5.130:33063"
group_replication_bootstrap_group=off
group_replication_unreachable_majority_timeout=60
group_replication_single_primary_mode = 1
#group_replication_enforce_update_everywhere_checks = 1


# innodb settings #
innodb_buffer_pool_size = 128M
innodb_buffer_pool_instances = 2
innodb_flush_log_at_trx_commit  = 1

 #启动MySQL

/usr/local/mysql/bin/mysqld_safe  --defaults-file=/etc/my3306.cnf  --user=mysql &

/usr/local/mysql/bin/mysqld_safe  --defaults-file=/etc/my3307.cnf  --user=mysql &

/usr/local/mysql/bin/mysqld_safe  --defaults-file=/etc/my3308.cnf  --user=mysql &

2、MGR配置

#记住哦 my3306.cnf，my3307.cnf、my3308.cnf的端口与server id差异哦，

group_replication_local_address 这里要改的

plugin_load_add='group_replication.so'
group_replication_group_name="aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"
group_replication_start_on_boot=off
group_replication_local_address= "192.168.5.130:33061"
group_replication_group_seeds= "192.168.5.130:33061,192.168.5.130:33062,192.168.5.130:33063"
group_replication_bootstrap_group=off
group_replication_unreachable_majority_timeout=60
group_replication_single_primary_mode = 1

3、主库执行(首次启动组的过程称为引导，只需要在其中一台服务器上执行一次，此库即为主库)

CREATE USER repl@'%' IDENTIFIED BY 'mysqldb@1025';
GRANT REPLICATION SLAVE ON *.* TO repl@'%';
FLUSH PRIVILEGES;

CHANGE MASTER TO MASTER_USER='repl', MASTER_PASSWORD='mysqldb@1025' FOR CHANNEL 'group_replication_recovery';

INSTALL PLUGIN group_replication SONAME 'group_replication.so';

首次启动组的过程称为引导，只需要在一台服务器上执行一次，此库即为主库：
SET GLOBAL group_replication_bootstrap_group=ON;
START GROUP_REPLICATION;
SET GLOBAL group_replication_bootstrap_group=OFF;

#查询集群状态
SELECT * FROM performance_schema.replication_group_members;

4、从库执行：
CHANGE MASTER TO MASTER_USER='repl', MASTER_PASSWORD='mysqldb@1025' FOR CHANNEL 'group_replication_recovery';

START GROUP_REPLICATION;

#查询集群状态
SELECT * FROM performance_schema.replication_group_members;