怎样实现Mycat读写分离与负载均衡,很多新手对此不是很清楚,为了帮助大家解决这个难题,下面小编将为大家详细讲解,有这方面需求的人可以来学习下,希望你能有所收获。

我们来学习读写分离与负载均衡
先看一下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。

3.writeType="2",没实现。






所以我们根据第二种方式做负载均衡

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

<dataNode name="dn2" dataHost="localhost2" database="examdb" />

<dataNode name="dn3" dataHost="localhost3" database="examdb" />




<dataHost name="localhost1" maxCon="1000" minCon="10" balance="2"

writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100">

<heartbeat>select user()</heartbeat>

<!-- can have multi write hosts -->

<writeHost host="hostM1" url="192.168.6.121:3306" user="root"

password="ESBecs00">

<!-- can have multi read hosts -->

</writeHost>



<writeHost host="hostS1" url="192.168.6.121:3307" user="root"

password="ESBecs00">

<!-- can have multi read hosts -->

</writeHost>

</dataHost>



<dataHost name="localhost2" maxCon="1000" minCon="10" balance="2"

writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100">

<heartbeat>select user()</heartbeat>

<!-- can have multi write hosts -->

<writeHost host="hostM1" url="192.168.6.120:3306" user="root"

password="ESBecs00">

<!-- can have multi read hosts -->

</writeHost>


<writeHost host="hostS1" url="192.168.6.120:3307" user="root"

password="ESBecs00">

<!-- can have multi read hosts -->

</writeHost>


</dataHost>


<dataHost name="localhost3" maxCon="1000" minCon="10" balance="2"

writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100">

<heartbeat>select user()</heartbeat>

<!-- can have multi write hosts -->

<writeHost host="hostM1" url="192.168.6.119:3306" user="root"

password="ESBecs00">

<!-- can have multi read hosts -->

</writeHost>


<writeHost host="hostM1" url="192.168.6.119:3307" user="root"

password="ESBecs00">

<!-- can have multi read hosts -->

</writeHost>


</dataHost>

测试

#!/usr/bin/bash
for((i=1;i<=1000;i++))
do
mysql -uroot -p123456 -P8066 -h227.0.0.1 -e "select name from company" TESTDB;
done

root@localhost logs]# sort test-blance.log |more |uniq -c

30 this is 119
17 this is 119:3307
28 this is 120
23 this is 120:3307
36 this is 121
26 this is 121:3307

如上:6台机器全部都有读到,读负载均衡成功

看完上述内容是否对您有帮助呢?如果还想对相关知识有进一步的了解或阅读更多相关文章,请关注亿速云行业资讯频道,感谢您对亿速云的支持。