mysql半主从复制

mysql半主从复制

node3: 172.16.92.3/16 mariadb主服务器
node4: 172.16.92.4/16 mariadb从服务器
以上节点均为CentOS 7.1

配置环境
1. 配置好光盘yum源
2. 关闭selinux和iptables


node3: mariadb主服务器

[root@node3 ~]# yum -y install mariadb-server
[root@node3 ~]# vim /etc/my.cnf
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
# Settings user and group are ignored when systemd is used.
# If you need to run mysqld under a different user or group,
# customize your systemd unit file for mariadb according to the
# instructions in http://fedoraproject.org/wiki/Systemd

#######以下的内容为添加########
#二进制变更日志
log-bin=mysql-bin
#二进制日志格式为混合模式
binlog_format=mixed
#为主服务器node3的ID值
server-id = 1
port = 3306
skip-external-locking
key_buffer_size = 256M
max_allowed_packet = 1M
table_open_cache = 256
sort_buffer_size = 1M
read_buffer_size = 1M
read_rnd_buffer_size = 4M
myisam_sort_buffer_size = 64M
thread_cache_size = 8
query_cache_size= 16M
thread_concurrency = 4
innodb_file_per_table = on
skip_name_resolve = on
###############################

###### 以下的内容可选 ########
[mysqldump]
quick
max_allowed_packet = 16M

[mysql]
no-auto-rehash

[myisamchk]
key_buffer_size = 128M
sort_buffer_size = 128M
read_buffer = 2M
write_buffer = 2M

[mysqlhotcopy]
interactive-timeout
#############################

[mysqld_safe]
log-error=/var/log/mariadb/mariadb.log
pid-file=/var/run/mariadb/mariadb.pid

#
# include all files from the config directory
#
!includedir /etc/my.cnf.d
############### End for my.cnf #################

[root@node3 ~]# rpm -ql mariadb-server | grep 'semisync'
/usr/lib64/mysql/plugin/semisync_master.so    #用于Master服务器安装的半同步插件
/usr/lib64/mysql/plugin/semisync_slave.so        #用于Slave服务器安装的半同步插件

[root@node3 ~]# systemctl start mariadb
[root@node3 ~]# mysql
MariaDB [(none)]> install plugin rpl_semi_sync_master soname 'semisync_master.so';     #安装Master半同步插件
MariaDB [(none)]> set global rpl_semi_sync_master_enabled = 1;    #开启Master半同步功能
MariaDB [(none)]> set global rpl_semi_sync_master_timeout = 2000;    #超时时间毫秒级
MariaDB [(none)]> grant replication client,replication slave on *.* to 'repluser'@'172.16.92.4' identified by 'replpass';
MariaDB [(none)]> flush privileges;
MariaDB [(none)]> show master status\G
*************************** 1. row ***************************
            File: mysql-bin.000003
        Position: 497
    Binlog_Do_DB:
Binlog_Ignore_DB:

##### 记下mysql-bin.000003 和 497 , 设置从服务器中继日志时有用 ####



node4: mariadb从服务器

[root@node4 ~]# yum -y install mariadb-server
[root@node4 ~]# vim /etc/my.cnf
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
# Settings user and group are ignored when systemd is used.
# If you need to run mysqld under a different user or group,
# customize your systemd unit file for mariadb according to the
# instructions in http://fedoraproject.org/wiki/Systemd

########## 添加以下内容 ##########
log-bin=mysql-bin
binlog_format=mixed
server-id = 2
relay-log = relay-bin
log_slave_updates = 1
read_only = on

port = 3306
skip-external-locking
key_buffer_size = 256M
max_allowed_packet = 1M
table_open_cache = 256
sort_buffer_size = 1M
read_buffer_size = 1M
read_rnd_buffer_size = 4M
myisam_sort_buffer_size = 64M
thread_cache_size = 8
query_cache_size= 16M
thread_concurrency = 4
innodb_file_per_table = on
skip_name_resolve = on
###################################

######### 以下内容可选 ############
[mysqldump]
quick
max_allowed_packet = 16M

[mysql]
no-auto-rehash

[myisamchk]
key_buffer_size = 128M
sort_buffer_size = 128M
read_buffer = 2M
write_buffer = 2M

[mysqlhotcopy]
interactive-timeout
####################################

[mysqld_safe]
log-error=/var/log/mariadb/mariadb.log
pid-file=/var/run/mariadb/mariadb.pid

#
# include all files from the config directory
#
!includedir /etc/my.cnf.d

############# End of my.cnf ###############

[root@node4 ~]# systemctl start mariadb
[root@node4 ~]# mysql
MariaDB [(none)]> show global variables like '%read_only%'\G
*************************** 1. row ***************************
Variable_name: read_only
        Value: ON

MariaDB [(none)]> change master to master_host='172.16.92.3',master_user='repluser',master_password='replpass',master_log_file='mysql-bin.000003',master_log_pos=497,master_connect_retry=5,master_heartbeat_period=2;
MariaDB [(none)]> install plugin rpl_semi_sync_slave soname 'semisync_slave.so';    #安装Slave半同步插件
MariaDB [(none)]> set global rpl_semi_sync_slave_enabled = 1;        #开启Slave半同步功能
MariaDB [(none)]> start slave;        #重启IO线程生效

MariaDB [(none)]> show slave status\G
*************************** 1. row ***************************
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
    ........ 其余信息略 ........

MariaDB [(none)]> show processlist\G
*************************** 3. row ***************************
   State: Slave has read all relay log; waiting for the slave I/O thread to update it
    ........ 其余信息略 ........说明: 从节点已经接收到所有的中继日志

MariaDB [(none)]> show global status like '%semi%';
| Rpl_semi_sync_slave_status | ON |#半同步状态已经开启了；

MariaDB [(none)]> show global variables like '%rpl%';
| rpl_semi_sync_slave_enabled | ON |#从服务器节点的半同步已经开启；


node3 主节点上可查看到此进程
MariaDB [(none)]> show processlist\G
*************************** 2. row ***************************
   State: Master has sent all binlog to slave; waiting for binlog to be updated
    ........ 其余信息略 ........

MariaDB [(none)]> show global status like 'rpl_semi%';
| Rpl_semi_sync_master_clients | 1 |    #可以看出有一个半同步客户端了；
    ........ 其余信息略 ........

在主节点上创建数据库测试是否能主从半同步
MariaDB [(none)]> create database testdb;

在从节点上可看到testdb数据库, 说明主从同步成功!
MariaDB [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| test               |
| testdb             |
+--------------------+

再来看一下 从节点 的状态
MariaDB [(none)]> show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 172.16.92.3
                  Master_User: repluser
                  Master_Port: 3306
                Connect_Retry: 5
              Master_Log_File: mysql-bin.000003
          Read_Master_Log_Pos: 584        #497->584
               Relay_Log_File: relay-bin.000002
                Relay_Log_Pos: 616            #529->616
        Relay_Master_Log_File: mysql-bin.000003
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes


############# mysql半主从复制结束 ##############