# 基于Mysql8.0搭建mysql双主互为主从
**据说mysql8.0比之前版本快两倍，哈哈**
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环境：ubuntu18.04-server
master1：192.168.11.241
master2：192.168.11.242
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### 1.到官网下载对应的二进制软件包，解压缩到／usr/local/mysql
```
tar -xf mysql-8.0.12-linux-glibc2.12-x86_64.tar.xz
mv mysql-8.0.12-linux-glibc2.12-x86_64 /usr/local/mysql
```
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### 2.创建mysql 用户，最好是不能登录到，创建mysql组
groupadd mysql
useradd -g mysql mysql
### 3.创建关于mysql的目录：
mkdir -pr /data/mysql
cd /data/mysql
mkdir {tmp,log,data,dumps,undo}
### 4. 给予相关目录mysql的权限
chown mysql.mysql /usr/local/mysql -R
chown mysql.mysql /data/mysql -R
### 5.导入环境变量
echo export PATH=$PATH:/usr/local/mysql/bin >> /etc/profile
### 6.一定要创建mysql的error.log ,mysql8.0启动不会自动创建，而且没有这个文件会报错
touch /data/mysql/log/error.log
### 7.创建mysql的配置文件my.cnf
我们的my.cnf放在/usr/local/mysql/etc/my.cnf
```
Vim /etc/my.cnf
[client]
socket=/data/mysql/data/mysql.sock
[mysqld]
server-id=2
port = 3306
log-bin=/data/mysql/data/binlog
basedir=/usr/local/mysql
datadir=/data/mysql/data
socket=/data/mysql/data/mysql.sock
log-error=/data/mysql/log/mysqld.log
pid-file=/data/mysql/data/mysqld.pid
slow_query_log_file = /data/mysql/log/slow.log
default_authentication_plugin=mysql_native_password
```
**这里也给出master2的my.cnf**
```
[client]
socket=/data/mysql/data/mysql.sock
[mysqld]
server-id=3
port = 3306
log-bin=/data/mysql/data/binlog
basedir=/usr/local/mysql
datadir=/data/mysql/data
socket=/data/mysql/data/mysql.sock
log-error=/data/mysql/log/mysqld.log
pid-file=/data/mysql/data/mysqld.pid
slow_query_log_file = /data/mysql/log/slow.log
default_authentication_plugin=mysql_native_password
```
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### 8.初始化mysql，并且得到mysql的初始密码
在ubuntu系统中初始化时会提示找不到libao.so.1这个文件，我们可以通过如下操作来解决
apt-get update
apt-get install libaio*
初始化操作
mysqld --initialize --basedir=/usr/local/mysql —datadir=/data/mysql/data
我们在日志中可以grep出我们的密码
grep pass /data/mysql/log/mysqld.log
2018-09-03T05:42:56.253317Z 5 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: Th<urDpY4tAl
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### 9.在配置好我们的my.cnf文件后，我们来启动我们的mysql
```
mysqld_safe --defaults-file=/usr/local/mysql/etc/my.cnf --user=mysql --basedir=/usr/local/mysql --datadir=/data/mysql/data 2>&1 > /dev/null &
root@test-db-11-242:/home/ubuntu# ss -tunlp |grep mysql
tcp LISTEN 0 70 *:33060 *:* users:(("mysqld",pid=40113,fd=26))
tcp LISTEN 0 151 *:3306 *:* users:(("mysqld",pid=40113,fd=19))
我们的mysql服务就启动起来了
```
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### 10.我们为我们的mysql服务配置启动项
cd /usr/local/mysql/support-files
cp mysql.server /etc/init.d/
下次启动就可以通过/etc/init.d/mysql-servce restart 来启动了
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### 11.我们登录到我们的mysql中，去为mysql主主复制来创建用户并且授权
1.更改root的密码
Use mysql;
ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY ‘你的新密码’;
2,创建用户：
create user 'user'@'%' identified by ‘密码';
3.授权：
grant all on *.* to ‘user'@'%';
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### 12.两台配置好了复制用户并且授权以后，我们就来进行主从同步
首先，把一台当作主，一台当作从
现在主的上面执行：
show master status/G
获取二进制日志的偏移量，和 position
```
mysql> show master status;
+---------------+----------+--------------+------------------+------------------------------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+---------------+----------+--------------+------------------+------------------------------------------+
| binlog.000008 | 23486999 | | | 34fdc5ef-af3c-11e8-ba35-000c29dff316:1-5 |
+---------------+----------+--------------+------------------+------------------------------------------+
```
在从上面执行：
```
master_host='172.16.63.129',master_user='slave',master_password='password',master_port=3306,MASTER_LOG_FILE='mysql-bin.000007', MASTER_LOG_POS=1068;
```
注意对应的地方改为所查的值，
在执行：start slave；
然后在执行：show slave status;
```
mysql> show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.11.241
Master_User: tom
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: binlog.000011
Read_Master_Log_Pos: 23484763
Relay_Log_File: test-db-11-242-relay-bin.000012
Relay_Log_Pos: 23482786
Relay_Master_Log_File: binlog.000011
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 23484763
Relay_Log_Space: 23483167
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 2
Master_UUID: 73b7dc2d-af36-11e8-bbf1-000c296da46c
Master_Info_File: mysql.slave_master_info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
Master_Retry_Count: 86400
Master_Bind:
Last_IO_Error_Timestamp:
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set: 34fdc5ef-af3c-11e8-ba35-000c29dff316:1-5
Auto_Position: 0
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
Master_public_key_path:
Get_master_public_key: 0
1 row in set (0.00 sec)
```
这就就算做好了主从复之，最后在把主的当成从的，从的当成主的，按上面的步奏操作，最后两边都可以看到两个yes
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### 13.测试，往一台上面写数据，看另一台能否同步。
