mycat 1.6.6.1安装以及配置docker 安装mysql 5.7.24 双主多从读写分离主主切换

mycat和mysql的高可用参考如下两个图

简介：应用程序仅需要连接HAproxy或者mycat，后端服务器的读写分离由mycat进行控制，后端服务器数据的同步由MySQL主从同步进行控制。

服务器主机规划

IP	功能	备注
192.168.0.200	Mysql Master1	Mysql Master1端口3306
192.168.0.199	mycat1 ,Mysql Slave1	mycat1端口8066 ,Mysql Slave1端口3306
192.168.0.198	mycat2 ,Mysql Slave2	mycat2端口8066 ,Mysql Slave2端口3306
192.168.0.170	Mysql Master2	Mysql Master2端口3306
192.168.0.169	Mysql Slave3	Mysql Slave3端口3306
192.168.0.168	Mysql Slave4	Mysql Slave4端口3306

安装MySQL数据库

1)使用docker安装完成mysql5.7.24，我规划的是3台：

192.168.0.200（Master1）

192.168.0.199（Slave1）

192.168.0.198（Slave2）

2)配置三台机器的my.cnf配置文件

我三台机器的配置文件都是/usr/local/mysql/conf/my.cnf

3)设置三台主从服务器配置
vi /usr/local/mysql/conf/my.cnf

[mysql]
default-character-set=utf8
[mysqld]
interactive_timeout = 120

wait_timeout = 120
max_allowed_packet = 32M
log-bin=mysql-bin
server-id=200

character-set-server=utf8

log-slave-updates
auto-increment-increment = 2
auto-increment-offset = 1

default-time_zone = '+8:00'

vi /usr/local/mysql/conf/my.cnf

[mysql]
default-character-set=utf8
[mysqld]
interactive_timeout = 120
wait_timeout = 120
max_allowed_packet = 32M
log-bin=mysql-bin
server-id=199
character-set-server=utf8

default-time_zone = '+8:00'

vi /usr/local/mysql/conf/my.cnf

[mysql]
default-character-set=utf8
[mysqld]
interactive_timeout = 120
wait_timeout = 120
max_allowed_packet = 32M
log-bin=mysql-bin
server-id=198

character-set-server=utf8

default-time_zone = '+8:00'

3)创建主从服务器容器

在200,199,198上运行启动mysql

docker run --name mysql5_7_24 -p 3306:3306 -v /usr/local/mysql/conf:/etc/mysql/conf.d -v /usr/local/mysql/log:/var/log/mysql -v /usr/local/mysql/data:/var/lib/mysql --privileged=true -e MYSQL_ROOT_PASSWORD=root -d mysql:5.7.24

接下来配置主从

4)登录200主服务器的mysql，查询master的状态

200主库创建用户

SET sql_mode=(SELECT REPLACE(@@sql_mode,'ONLY_FULL_GROUP_BY',''));
GRANT REPLICATION SLAVE ON *.* to 'backup'@'%' identified by '123456';

5)登录199和198从服务器的mysql，设置与主服务器相关的配置参数

SET sql_mode=(SELECT REPLACE(@@sql_mode,'ONLY_FULL_GROUP_BY',''));
change master to master_host='192.168.0.200',master_user='backup',master_password='123456',master_log_file='mysql-bin.000003',master_log_pos=441;

master_host为docker的地址不能写127.0.0.1
master_user是在主库创建的用户
master_log_pos是主库show master status;查询出的Position

然后在199和198上启动服务

start slave;

查看服务状态

show slave status;

Waiting for master to send event 就是成功了
Connecting to master 多半是连接不通

之后主库的修改都能同步到从库了

接下来安装Mysql Master2和Mysql Slave3和Mysql Slave4使用docker安装完成mysql5.7.24，我规划的是3台：

192.168.0.170（Master1）

192.168.0.169（Slave3）

192.168.0.168（Slave4）

具体安装方法和上面一致，我只贴出170，169，168的mysql 配置文件如下

170的配置文件

vi /usr/local/mysql/conf/my.cnf

[mysql]
default-character-set=utf8
[mysqld]
interactive_timeout = 120

wait_timeout = 120
max_allowed_packet = 32M
log-bin=mysql-bin
server-id=170

character-set-server=utf8

log-slave-updates
auto-increment-increment = 2
auto-increment-offset = 2

default-time_zone = '+8:00'

169的配置文件

vi /usr/local/mysql/conf/my.cnf

[mysql]
default-character-set=utf8
[mysqld]
interactive_timeout = 120
wait_timeout = 120
max_allowed_packet = 32M
log-bin=mysql-bin
server-id=169
character-set-server=utf8

default-time_zone = '+8:00'

168的配置文件

vi /usr/local/mysql/conf/my.cnf

[mysql]
default-character-set=utf8
[mysqld]
interactive_timeout = 120
wait_timeout = 120
max_allowed_packet = 32M
log-bin=mysql-bin
server-id=168

character-set-server=utf8

default-time_zone = '+8:00'

依照200,199,198配置好170,169,168的主从同步后，接下来我们配置

200和170的主主同步：

先查询170的 SHOW MASTER STATUS

然后在200这个mysql上执行如下语句

SET sql_mode=(SELECT REPLACE(@@sql_mode,'ONLY_FULL_GROUP_BY',''));
change master to master_host='192.168.0.170',master_user='backup',master_password='123456',master_log_file='mysql-bin.000009',master_log_pos=154;

然后执行 start slave;

然后执行show slave status; 查看同步状态

然后再先查询200的 SHOW MASTER STATUS

然后在170这个mysql上执行如下语句

然后执行 start slave;

然后执行show slave status; 查看同步状态，现在170和200配置成功主主同步了，但是我的200,199,198是比170,169,168晚安装2个多月，所以170上面有几万条记录需要通过mysqldump和source手动同步到200上，发现大量数据不一致的时候可以分别在170和200上把主主同步停了，stop slave; 再执行下面步骤具体步骤如下：

这个时候如果发现170和200数据大量不同步，可以采取下面的方式解决

解决步骤如下：

先确保170和200都执行了stop slave;停止主主同步

1.先进入主库170，进行锁表，防止数据写入（也可以用SQLyog执行flush tables with read lock;等等语句，我用windows的cmd连docker安装的mysql5.7.24大概1分钟就自动退出）

C:\Users\1111>mysql -uroot -p -h192.168.0.170
Enter password: ****
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 129
Server version: 5.7.24-log MySQL Community Server (GPL)

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql>

使用命令锁定为只读（必须use指定数据库不然锁定只读不生效）：

mysql> use novadb2;

mysql> flush tables with read lock;

注意：该处是锁定为只读状态，语句不区分大小写

2.进行数据备份

把170的数据备份到novadb2_20190212.sql文件

mysqldump -uroot -p -h192.168.0.170 novadb2 -e --max_allowed_packet=1048576 --net_buffer_length=16384 >C:\nova_work_document\novaold_mysqldb_backup\novadb2_20190212.sql

这里注意一点：数据库备份一定要定期进行，可以用shell脚本或者python脚本，都比较方便，确保数据万无一失

3.停止从库200的状态
mysql> stop slave;

4.然后到从库200执行mysql命令，导入数据备份

mysql> use novadb2

mysql> source C:\nova_work_document\novaold_mysqldb_backup\novadb2_20190212.sql

5.查看master 170的状态

6.设置从库200同步，注意该处的同步点，就是170主库show master status信息里的| File| Position两项

7.重新开启从200的同步
mysql> start slave;

9.查看200的同步状态
mysql> show slave status\G 查看：

Slave_IO_Running: Yes
Slave_SQL_Running: Yes

同理按照上面步骤在170上也配置从200同步，启动start slave;

好了，同步完成啦

最后把主库170解除只读锁定

mysql> use novadb2;

mysql> unlock tables;

mycat安装

cd /root
wget http://dl.mycat.io/1.6.6.1/Mycat-server-1.6.6.1-release-20181031195535-linux.tar.gz
tar -zxvf Mycat-server-1.6.6.1-release-20181031195535-linux.tar.gz

 
如果没有配置jdk那么执行 tar -zxvf jdk-8u131-linux-x64.gz
并且在/etc/profile的最后加上

JAVA_HOME=/root/jdk1.8.0_131
JRE_HOME=/root/jdk1.8.0_131/jre

MYCAT_HOME=/root/mycat
PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin:$MYCAT_HOME/bin
CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/lib
export JAVA_HOME JRE_HOME MYCAT_HOME PATH CLASSPATH

然后执行source /etc/profile使配置生效

修改server.xml

进入/root/mycat/conf

cp server.xml server2019_bak.xml

vim server.xml

然后对如下截图的几个地方进行修改

接下来修改schema.xml

cp schema.xml schema2019_bak.xml

vim schema.xml

修改为如下内容

<?xml version="1.0"?>
<!DOCTYPE mycat:schema SYSTEM "schema.dtd">
<mycat:schema xmlns:mycat="http://io.mycat/">

<schema name="NOVADB" checkSQLschema="false" sqlMaxLimit="100">

<table name="e_instance_step_status_" primaryKey="step_id" subTables="e_instance_step_status_$1-20" dataNode="dn1" rule="sharding-by-murmur" />
<table name="e_config_match" dataNode="dn1" />
<table name="e_instance" dataNode="dn1" />
<table name="e_task" dataNode="dn1" />
<table name="e_task_plan" dataNode="dn1" />
<table name="m_category" dataNode="dn1" />
<table name="m_component_platform" dataNode="dn1" />
<table name="m_configitem" dataNode="dn1" />
<table name="m_dish" dataNode="dn1" />
<table name="m_dish_detail" dataNode="dn1" />
<table name="m_instanceset" dataNode="dn1" />
<table name="m_instanceset_detail" dataNode="dn1" />
<table name="m_instanceset_detail_config" dataNode="dn1" />
<table name="m_instanceset_row" dataNode="dn1" />
<table name="m_odm_company" dataNode="dn1" />
<table name="m_odminfo" dataNode="dn1" />
<table name="m_permission" dataNode="dn1" />
<table name="m_platform_hwphase" dataNode="dn1" />
<table name="m_platform_n" dataNode="dn1" />
<table name="m_platform_sku" dataNode="dn1" />
<table name="m_platform_sku_detail" dataNode="dn1" />
<table name="m_role" dataNode="dn1" />
<table name="m_role_permission" dataNode="dn1" />
<table name="m_user" dataNode="dn1" />
<table name="m_user_role" dataNode="dn1" />
<table name="t_attachments" dataNode="dn1" />
<table name="t_case" dataNode="dn1" />
<table name="t_case_section" dataNode="dn1" />
<table name="t_caseorsect_plan" dataNode="dn1" />
<table name="t_config_match" dataNode="dn1" />
<table name="t_instance" dataNode="dn1" />
<table name="t_instance_struct_" primaryKey="struct_id" subTables="t_instance_struct_$1-20" dataNode="dn1" rule="sharding-by-murmur" />
<table name="t_plan" dataNode="dn1" />
<table name="t_section" dataNode="dn1" />
<table name="t_step" dataNode="dn1" />
<table name="t_tag" dataNode="dn1" />
<table name="t_tag_category" dataNode="dn1" />
<table name="t_tag_obj" dataNode="dn1" />
<table name="t_task" dataNode="dn1" />
<table name="t_task_instance_row" dataNode="dn1" />
<table name="t_task_plan" dataNode="dn1" />
<table name="t_tasksendstatus" dataNode="dn1" />







</schema>

<dataNode name="dn1" dataHost="localhost1" database="novadb2" />


<dataHost name="localhost1" maxCon="1000" minCon="10" balance="1"
writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100">
<heartbeat>select user()</heartbeat>

<writeHost host="Master1" url="192.168.0.200:3306" user="root"
password="root">

<readHost host="Slave1" url="192.168.0.199:3306" user="root" password="root" />
<readHost host="Slave2" url="192.168.0.198:3306" user="root" password="root" />
</writeHost>
<writeHost host="Master2" url="192.168.0.170:3306" user="root"
password="root">

<readHost host="Slave3" url="192.168.0.169:3306" user="root" password="root" />
<readHost host="Slave4" url="192.168.0.168:3306" user="root" password="root" />
</writeHost>

</dataHost>
<!--
<dataHost name="sequoiadb1" maxCon="1000" minCon="1" balance="0" dbType="sequoiadb" dbDriver="jdbc">
<heartbeat> </heartbeat>
<writeHost host="hostM1" url="sequoiadb://1426587161.dbaas.sequoialab.net:11920/SAMPLE" user="jifeng" password="jifeng"></writeHost>
</dataHost>

<dataHost name="oracle1" maxCon="1000" minCon="1" balance="0" writeType="0" dbType="oracle" dbDriver="jdbc"> <heartbeat>select 1 from dual</heartbeat>
<connectionInitSql>alter session set nls_date_format='yyyy-mm-dd hh24:mi:ss'</connectionInitSql>
<writeHost host="hostM1" url="jdbc:oracle:thin:@127.0.0.1:1521:nange" user="base" password="123456" > </writeHost> </dataHost>

<dataHost name="jdbchost" maxCon="1000" minCon="1" balance="0" writeType="0" dbType="mongodb" dbDriver="jdbc">
<heartbeat>select user()</heartbeat>
<writeHost host="hostM" url="mongodb://192.168.0.99/test" user="admin" password="123456" ></writeHost> </dataHost>

</mycat:schema>

其中关键部分如下截图

balance="1": 全部的readHost与stand by writeHost参与select语句的负载均衡。
writeType="0": 所有写操作发送到配置的第一个writeHost，第一个挂了切到还生存的第二个 writeHost，重新启动后以切换后的为准，切换记录在配置文件中:dnindex.properties 。
switchType="1": 1 默认值，自动切换。


接下来修改rule.xml文件配置里面的一致性hash算法
vim rule.xml 
主要需要根据你的分表修改如下截图的内容
这个图是修改需要分表的字段

这个图是修改为一共多少个分表

启动mycat服务

mycat start

[root@localhost conf]# ss -lntup |egrep '(8066|9066)'
tcp LISTEN 0 100 :::9066 :::* users:(("java",pid=12589,fd=94))
tcp LISTEN 0 100 :::8066 :::* users:(("java",pid=12589,fd=98))

验证mycat服务是否正常

第一步：使用mysql的客户端连接mycat

C:\Windows\system32>mysql -uroot -p123456 -h192.168.0.199 -P8066
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 26
Server version: 5.6.29-mycat-1.6.6.1-release-20181031195535 MyCat Server (OpenCloudDB)

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> show databases;
+----------+
| DATABASE |
+----------+
| NOVADB |
+----------+
1 row in set (0.00 sec)

mysql> use NOVADB;
Database changed

mysql> select * from t_tag;
+----+-------------+-------------+---------------+---------------------+
| id | tag_name | category_id | category_name | createtime |
+----+-------------+-------------+---------------+---------------------+
| 1 | aaa | 1 | bb | 2019-01-17 16:38:30 |
| 2 | bbb | 1 | bb | 2019-01-17 16:38:48 |
| 3 | adasdqw | 1 | bb | 2019-01-18 11:23:22 |
| 5 | ww | 27 | qq | 2019-01-21 18:14:24 |
| 6 | dasdsad | 28 | dsadsa | 2019-01-23 13:57:47 |
| 7 | gfdgf | 29 | gffd | 2019-01-23 14:01:51 |
| 8 | N | 30 | automation | 2019-01-23 15:15:45 |
| 9 | ccccccc | 31 | wang | 2019-01-23 16:04:56 |
| 11 | ww | 35 | BB | 2019-01-23 17:07:30 |
| 12 | dasdsadsa | 36 | dasdasd | 2019-01-24 18:43:16 |
| 13 | 22222222 | 37 | 1111111111 | 2019-01-24 18:43:16 |
| 14 | 44444444444 | 38 | 3333333333 | 2019-01-24 18:43:16 |
+----+-------------+-------------+---------------+---------------------+
12 rows in set (0.00 sec)

第二步：也可以通过连接9066这个mycat的监控管理端口查看Mycat的读写情况

C:\Windows\system32>mysql -uroot -p123456 -h192.168.0.199 -P9066

mysql> show @@datasource;
+----------+---------+-------+---------------+------+------+--------+------+------+---------+-----------+------------+
| DATANODE | NAME | TYPE | HOST | PORT | W/R | ACTIVE | IDLE | SIZE | EXECUTE | READ_LOAD | WRITE_LOAD |
+----------+---------+-------+---------------+------+------+--------+------+------+---------+-----------+------------+
| dn1 | Master1 | mysql | 192.168.0.200 | 3306 | W | 0 | 10 | 1000 | 106 | 0 | 19 |
| dn1 | Master2 | mysql | 192.168.0.170 | 3306 | W | 0 | 1 | 1000 | 93 | 15 | 0 |
| dn1 | Slave1 | mysql | 192.168.0.199 | 3306 | R | 0 | 6 | 1000 | 100 | 16 | 0 |
| dn1 | Slave2 | mysql | 192.168.0.198 | 3306 | R | 0 | 7 | 1000 | 102 | 18 | 0 |
| dn1 | Slave3 | mysql | 192.168.0.169 | 3306 | R | 0 | 7 | 1000 | 103 | 19 | 0 |
| dn1 | Slave4 | mysql | 192.168.0.168 | 3306 | R | 0 | 7 | 1000 | 100 | 16 | 0 |
+----------+---------+-------+---------------+------+------+--------+------+------+---------+-----------+------------+
6 rows in set (0.00 sec)

参考

mycat权威指南

故障汇总

第一次配置的时候mysql的Master1端和Master2没有配置log-slave-updates导致，slave1和slave2上没有Master1端的数据。
解释：
从库开启log-bin参数，如果直接往Master1写数据，是可以记录log-bin日志的，但是Master1通过I0线程读取主主同步Master2二进制日志文件，然后通过SQL线程写入的数据，是不会记录binlog日志的。也就是说主主从库Master1从主库Master2上复制的数据，是不写入主主从库Master1的binlog日志的。所以主主从库Master1做为其他从库的主库时需要在配置文件中添加log-slave-updates参数。Master1和Master2都一样

解决办法：

[mysqld]
log-slave-updates