mycat 测试主从读写分离

下载解压及创建用户组和目录属性

下载地址：1、https://github.com/MyCATApache/Mycat-download。2、http://dl.mycat.io/
wget http://dl.mycat.io/1.6.6.1/Mycat-server-1.6.6.1-release-20180908155252-linux.tar.gz
tar -zxf Mycat-server-1.6.6.1-release-20180908155252-linux.tar.gz -C /usr/local/
groupadd mycat
useradd mycat -g mycat
chown -R mycat:mycat mycat

　　mycat主要配置3个参数文件需要配置

--server.xml：是Mycat服务器参数调整和用户授权的配置文件。
--schema.xml：是逻辑库定义和表以及分片定义的配置文件。
--rule.xml：  是分片规则的配置文件，分片规则的具体一些参数信息单独存放为文件，也在这个目录下，配置文件修改需要重启MyCAT。

　　配置server.xml

server.xml,用户权限及表的精细权限
         <user name="ht">
                <property name="password">ocm123</property>
                <property name="schemas">sakila</property>
        </user>

　　配置schema.xml

[mycat@redis04 conf]$ cat schema.xml
<?xml version="1.0"?>
<!DOCTYPE mycat:schema SYSTEM "schema.dtd">
<mycat:schema xmlns:mycat="http://io.mycat/">

	<schema name="sakila" checkSQLschema="false" sqlMaxLimit="100" dataNode="dn1"> </schema>
	<dataNode name="dn1" dataHost="localhost1" database="sakila" />
	<dataHost name="localhost1" maxCon="1000" minCon="10" balance="1"  writeType="0" dbType="mysql" dbDriver="native" switchType="1"  slaveThreshold="100">
		<heartbeat>select user()</heartbeat>
		<!-- can have multi write hosts -->
		<writeHost host="hostM1" url="192.168.20.201:3306" user="ht"  password="ocm123">
			<!-- can have multi read hosts -->
			<readHost host="hostS2" url="192.168.20.203:3306" user="ht" password="ocm123" />
		</writeHost>
		<!-- <writeHost host="hostM2" url="localhost:3316" user="root" password="123456"/> -->
	</dataHost>
</mycat:schema>

schema.xml schema的值与server.xml中schema的值是多对1的关系，server.xml中schema的值可以是多个、schema.xml schema的值是唯一，可以有多个schema。schema 相对于mysql中的database
dataNode 数据分片。一个dataNode标签就是一个独立的数据分片。
dataHost 物理主机
balance属性
负载均衡类型，目前的取值有3种：
1. balance="0", 不开启读写分离机制，所有读操作都发送到当前可用的writeHost上。
2. balance="1"，全部的readHost与stand by writeHost参与select语句的负载均衡，简单的说，当双主双从模式(M1->S1，M2->S2，并且M1与 M2互为主备)，正常情况下，M2,S1,S2都参与select语句的负载均衡。
3. balance="2"，所有读操作都随机的在writeHost、readhost上分发。
4. balance="3"，所有读请求随机的分发到wiriterHost对应的readhost执行，writerHost不负担读压力，注意balance=3只在1.4及其以后版本有，1.3没有。
writeType属性
负载均衡类型，目前的取值有3种：
1. 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，重新启动后已切换后的为准，切换记录在配置文件中:dnindex.properties .
2. writeType="1"，所有写操作都随机的发送到配置的writeHost，1.5以后废弃不推荐。
switchType属性
- -1 表示不自动切换
- 1 默认值，自动切换
- 2 基于MySQL主从同步的状态决定是否切换
- 3 基于MySQL galary cluster的切换机制（适合集群）（1.4.1）心跳语句为 show status like ‘wsrep%’.

　　启动mycat

mycat start 启动
mycat stop 停止
mycat console 前台运行
mycat restart 重启服务
mycat pause 暂停
mycat status 查看启动状态

　　连接和管理mycat

mysql -h 192.168.20.204 -P 8066 -u ht -p    --应该用连接
mysql -h 192.168.20.204 -P 9066 -u ht -p    --管理 ,查看mycat的详细信息

　　打开mycat日志debug，为下面查看具体路由和调试做准备

vi log4j2.xml
 <!--<AsyncLogger name="io.mycat" level="debug" includeLocation="true" additivity="false">-->
            <!--<AppenderRef ref="Console"/>-->
            <!--<AppenderRef ref="RollingFile"/>-->
        <!--</AsyncLogger>-->

　　执行select语句看后台日志

SELECT * from sakila.actor a where a.actor_id=1;

2018-09-12 14:13:42.433 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.server.ServerQueryHandler.query(ServerQueryHandler.java:57)) - ServerConnection [id=1, schema=null, host=192.168.20.204, user=ht,txIsolation=3, autocommit=true, schema=null]SELECT * from sakila.actor a where a.actor_id=1
2018-09-12 14:13:42.434 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.cache.impl.EnchachePool.get(EnchachePool.java:77)) - SQLRouteCache  miss cache ,key:sakilaSELECT * from sakila.actor a where a.actor_id=1
2018-09-12 14:13:42.434 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.server.NonBlockingSession.execute(NonBlockingSession.java:126)) - ServerConnection [id=1, schema=null, host=192.168.20.204, user=ht,txIsolation=3, autocommit=true, schema=null]SELECT * from sakila.actor a where a.actor_id=1, route={
   1 -> dn1{SELECT * from sakila.actor a where a.actor_id=1}
} rrs
2018-09-12 14:13:42.434 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.mysql.nio.handler.SingleNodeHandler.execute(SingleNodeHandler.java:167)) - rrs.getRunOnSlave() default
2018-09-12 14:13:42.434 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.mysql.nio.handler.SingleNodeHandler.execute(SingleNodeHandler.java:169)) - node.getRunOnSlave()  default
2018-09-12 14:13:42.434 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.mysql.nio.handler.SingleNodeHandler.execute(SingleNodeHandler.java:178)) - node.getRunOnSlave()  default
2018-09-12 14:13:42.434 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.mysql.nio.handler.SingleNodeHandler.execute(SingleNodeHandler.java:180)) - node.getRunOnSlave()  default
2018-09-12 14:13:42.434 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.datasource.PhysicalDBNode.getConnection(PhysicalDBNode.java:96)) - rrs.getRunOnSlave()  default
2018-09-12 14:13:42.434 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.datasource.PhysicalDBNode.getConnection(PhysicalDBNode.java:127)) - rrs.getRunOnSlave()  default
2018-09-12 14:13:42.434 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.datasource.PhysicalDBPool.getRWBanlanceCon(PhysicalDBPool.java:530)) - select read source hostS2 for dataHost:localhost1
2018-09-12 14:13:42.434 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.mysql.nio.MySQLConnection.synAndDoExecute(MySQLConnection.java:462)) - con need syn ,total syn cmd 1 commands SET names utf8;schema change:false con:MySQLConnection [id=13, lastTime=1536732822434, user=ht, schema=sakila, old shema=sakila, borrowed=true, fromSlaveDB=true, threadId=357, charset=utf8, txIsolation=3, autocommit=true, attachment=dn1{SELECT * from sakila.actor a where a.actor_id=1}, respHandler=SingleNodeHandler [node=dn1{SELECT * from sakila.actor a where a.actor_id=1}, packetId=0], host=192.168.20.203, port=3306, statusSync=null, writeQueue=0, modifiedSQLExecuted=false]

　　执行update语句查看后台日志

update sakila.actor  a set a.last_name='sahnghai' where a.actor_id=1;

2018-09-12 14:13:41.830 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.server.NonBlockingSession.execute(NonBlockingSession.java:126)) - ServerConnection [id=1, schema=null, host=192.168.20.204, user=ht,txIsolation=3, autocommit=true, schema=null]update sakila.actor  a set a.last_name='sahnghai' where a.actor_id=1, route={
   1 -> dn1{update sakila.actor  a set a.last_name='sahnghai' where a.actor_id=1}
} rrs
2018-09-12 14:13:41.830 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.mysql.nio.handler.SingleNodeHandler.execute(SingleNodeHandler.java:167)) - rrs.getRunOnSlave() default
2018-09-12 14:13:41.830 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.mysql.nio.handler.SingleNodeHandler.execute(SingleNodeHandler.java:169)) - node.getRunOnSlave()  default
2018-09-12 14:13:41.830 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.mysql.nio.handler.SingleNodeHandler.execute(SingleNodeHandler.java:178)) - node.getRunOnSlave()  default
2018-09-12 14:13:41.830 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.mysql.nio.handler.SingleNodeHandler.execute(SingleNodeHandler.java:180)) - node.getRunOnSlave()  default
2018-09-12 14:13:41.830 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.datasource.PhysicalDBNode.getConnection(PhysicalDBNode.java:96)) - rrs.getRunOnSlave()  default
2018-09-12 14:13:41.830 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.datasource.PhysicalDBNode.getConnection(PhysicalDBNode.java:127)) - rrs.getRunOnSlave()  default
2018-09-12 14:13:41.830 DEBUG [$_NIOREACTOR-2-RW] (io.mycat.backend.mysql.nio.MySQLConnection.synAndDoExecute(MySQLConnection.java:462)) - con need syn ,total syn cmd 1 commands SET names utf8;schema change:false con:MySQLConnection [id=10, lastTime=1536732821830, user=ht, schema=sakila, old shema=sakila, borrowed=true, fromSlaveDB=false, threadId=410, charset=utf8, txIsolation=3, autocommit=true, attachment=dn1{update sakila.actor  a set a.last_name='sahnghai' where a.actor_id=1}, respHandler=SingleNodeHandler [node=dn1{update sakila.actor  a set a.last_name='sahnghai' where a.actor_id=1}, packetId=0], host=192.168.20.201, port=3306, statusSync=null, writeQueue=0, modifiedSQLExecuted=true]
2018-09-12 14:13:41.940 DEBUG [$_NIOREACTOR-1-RW] (io.mycat.server.NonBlockingSession.releaseConnection(NonBlockingSession.java:386)) - release connection MySQLConnection [id=10, lastTime=1536732821828, user=ht, schema=sakila, old shema=sakila, borrowed=true, fromSlaveDB=false, threadId=410, charset=utf8, txIsolation=3, autocommit=true, attachment=dn1{update sakila.actor  a set a.last_name='sahnghai' where a.actor_id=1}, respHandler=SingleNodeHandler [node=dn1{update sakila.actor  a set a.last_name='sahnghai' where a.actor_id=1}, packetId=1], host=192.168.20.201, port=3306, statusSync=null, writeQueue=0, modifiedSQLExecuted=true]

　　开启mycat日志看到读写分离测试成功