MyCat是一个彻底开源的,面向企业应用开发的大数据库集群,支持事务、ACID、可以替代MySQL的加强版数据库,其功能有可以视为MySQL集群的企业级数据库,用来替代昂贵的Oracle集群.融合了内存缓存技术、NoSQL技术、HDFS大数据的新型SQLServer,结合传统数据库和新型分布式数据仓库的新一代企业级数据库产品.
MyCat 读写分离
代码语言：javascript复制192.168.1.5 MyCat Server
192.168.1.11 Master 主MariaDB
192.168.1.12 Slave1 从1
192.168.1.13 Slave2 从21.在配置读写分离前请确保你的主机有四台,分别在每台主机安装MariaDB数据库,并初始化,需要注意的是MyCat服务端的MariaDB不需要初始化.
代码语言：javascript复制[root@localhost ~]# yum install -y mariadb mariadb-server
[root@localhost ~]# systemctl start mariadb
[root@localhost ~]# systemctl enable mariadb2.在MyCat服务端安装JDK环境,由于MyCat是使用Java开发的,在这里我们要先配置一下JDK环境.
代码语言：javascript复制[root@localhost ~]# tar -xzvf jdk-8u171-linux-x64.tar.gz -C /usr/local/
[root@localhost ~]# mv /usr/local/jdk1.8.0_171/ /usr/local/jdk
[root@localhost ~]# vim /etc/profile
#------------------------------------------------------------------
#JAVA-JDK-PATH
export JAVA_HOME=/usr/local/jdk
export JAVA_BIN=/usr/local/jdk/bin
export PATH=$PATH:$JAVA_HOME/bin
export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export JAVA_HOME JAVA_BIN PATH CLASSPATH
#------------------------------------------------------------------
[root@localhost ~]# source /etc/profile
[root@localhost ~]# java -version
java version "1.8.0_171"
Java(TM) SE Runtime Environment (build 1.8.0_171-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.171-b11, mixed mode)3.此步骤需要进入每一个数据库创建授权用户,也就是给MyCAT准备的使用数据库的授权用户.
代码语言：javascript复制[root@localhost ~]# mysql -uroot -p
Welcome to the MariaDB monitor. Commands end with ; or g.
Your MariaDB connection id is 10
Server version: 5.5.60-MariaDB MariaDB Server
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.
MariaDB [(none)]> create database MyCatDB;
Query OK, 1 row affected (0.00 sec)
MariaDB [(none)]> grant all on MyCatDB.* to "MyCat"@"%" identified by "123123";
Query OK, 0 rows affected (0.01 sec)
MariaDB [(none)]> grant all on MyCatDB.* to "MyCat"@"localhost" identified by "123123";
Query OK, 0 rows affected (0.00 sec)4.解压MyCat工具,并修改MyCat用户授权文件,写入MyCat登陆账户,这里配置文件有很多选项,我们不需要动,只需要修改以下几个地方就行.
代码语言：javascript复制[root@localhost ~]# wget http://dl.mycat.io/1.6.5/Mycat-server-1.6.5-release-20180122220033-linux.tar.gz
[root@localhost ~]# tar -xzvf Mycat-server-1.6.5-release-20180122220033-linux.tar.gz -C /usr/local/
[root@localhost ~]# vim /usr/local/mycat/conf/server.xml
<user name="root" defaultAccount="true"> #指定MyCat登陆用户名
<property name="password">123456</property> #指定密码
<property name="schemas">MyCatDB</property> #指定同步数据库
</user>
<user name="user"> #指定MyCat登陆用户名
<property name="password">123456</property> #指定密码
<property name="schemas">MyCatDB</property> #指定同步数据库
<property name="readOnly">true</property> #指定只读
</user>5.修改MyCat读写分离策略,这里我们删除源文件,并自己创建一个,写入以下内容.
代码语言：javascript复制[root@localhost ~]# vim /usr/local/mycat/conf/schema.xml
<?xml version="1.0"?>
<!DOCTYPE mycat:schema SYSTEM "schema.dtd">
<mycat:schema xmlns:mycat="http://io.mycat/">
<schema name="MyCatDB" checkSQLschema="false" sqlMaxLimit="100" dataNode="dn_test"> </schema>
<dataNode name="dn_test" dataHost="localhost" database="MyCatDB" />
<dataHost name="localhost" maxCon="1000" minCon="10" balance="1" writeType="0" dbType="mysql" dbDriver="native" switchType="1" slaveThreshold="100">
<heartbeat>select user()</heartbeat>
<writeHost host="Master1" url="192.168.1.11:3306" user="MyCat" password="123123"> #配置写主机
<readHost host="Slave1" url="192.168.1.12:3306" user="MyCat" password="123123" /> #配置读主机
<readHost host="Slave2" url="192.168.1.13:3306" user="MyCat" password="123123" /> #配置读主机
</writeHost>
</dataHost>
</mycat:schema>6.启动MyCat若无报错则说明启动成功,查看端口看虚拟端口是否开启成功.
代码语言：javascript复制[root@localhost ~]# /usr/local/mycat/bin/mycat start
[root@localhost ~]# netstat -an |grep "9066" #虚拟schema管理端口
[root@localhost ~]# netstat -an |grep "8066" #虚拟schema登陆端口7.在MyCat服务主机登陆数据库,测试同步效果.
代码语言：javascript复制[root@localhost ~]# mysql -uroot -p123456 -h 127.0.0.1 -P 9066
Welcome to the MariaDB monitor. Commands end with ; or g.
Your MySQL connection id is 2
Server version: 5.6.29-mycat-1.6.5-release-20180122220033 MyCat Server (monitor)
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.
MySQL [(none)]> show @@heartbeat; #RS_CODE为1表示心跳正常
--------- ------- -------------- ------ --------- ------- -------- --------- -------------- --------------------- -------
| NAME | TYPE | HOST | PORT | RS_CODE | RETRY | STATUS | TIMEOUT | EXECUTE_TIME | LAST_ACTIVE_TIME | STOP |
--------- ------- -------------- ------ --------- ------- -------- --------- -------------- --------------------- -------
| Master1 | mysql | 192.168.1.11 | 3306 | -1 | 0 | idle | 0 | 0,16,16 | 2018-12-21 01:29:43 | false |
| Slave1 | mysql | 192.168.1.12 | 3306 | -1 | 0 | idle | 0 | 34,31,31 | 2018-12-21 01:29:43 | false |
| Slave2 | mysql | 192.168.1.13 | 3306 | -1 | 0 | idle | 0 | 1,16,16 | 2018-12-21 01:29:43 | false |
--------- ------- -------------- ------ --------- ------- -------- --------- -------------- --------------------- -------
3 rows in set (0.00 sec)
MySQL [(none)]> show @@datasource; #查看读写分离的机器配置情况
---------- --------- ------- -------------- ------ ------ -------- ------ ------ --------- ----------- ------------
| DATANODE | NAME | TYPE | HOST | PORT | W/R | ACTIVE | IDLE | SIZE | EXECUTE | READ_LOAD | WRITE_LOAD |
---------- --------- ------- -------------- ------ ------ -------- ------ ------ --------- ----------- ------------
| dn_test | Master1 | mysql | 192.168.1.11 | 3306 | W | 0 | 0 | 1000 | 0 | 0 | 0 |
| dn_test | Slave1 | mysql | 192.168.1.12 | 3306 | R | 0 | 0 | 1000 | 0 | 0 | 0 |
| dn_test | Slave2 | mysql | 192.168.1.13 | 3306 | R | 0 | 0 | 1000 | 0 | 0 | 0 |
---------- --------- ------- -------------- ------ ------ -------- ------ ------ --------- ----------- ------------
3 rows in set (0.01 sec)
MySQL [(none)]>8.登录MyCat代理端,测试读写分离服务.
代码语言：javascript复制[root@localhost ~]# mysql -uroot -p123456 -h127.0.0.1 -P 8066
Welcome to the MariaDB monitor. Commands end with ; or g.
Your MySQL connection id is 3
Server version: 5.6.29-mycat-1.6.5-release-20180122220033 MyCat Server (OpenCloundDB)
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or 'h' for help. Type 'c' to clear the current input statement.
MySQL [(none)]>
MySQL [(none)]>
MySQL [(none)]>
MySQL [(none)]> show databases;
----------
| DATABASE |
----------
| MyCatDB |
----------
1 row in set (0.00 sec)
MySQL [(none)]>Web监控页配置
1.首先我们先来下载MyCat以及Zookeeper.
代码语言：javascript复制[root@localhost ~]# wget http://www-eu.apache.org/dist/zookeeper/zookeeper-3.4.12/zookeeper-3.4.12.tar.gz
[root@localhost ~]# wget http://dl.mycat.io/mycat-web-1.0/Mycat-web-1.0-SNAPSHOT-20170102153329-linux.tar.gz2.在MyCat服务端安装JDK环境,由于MyCat是使用Java开发的,在这里我们要先配置一下JDK环境.
代码语言：javascript复制[root@localhost ~]# tar -xzvf jdk-8u171-linux-x64.tar.gz -C /usr/local/
[root@localhost ~]# mv /usr/local/jdk1.8.0_171/ /usr/local/jdk
[root@localhost ~]# vim /etc/profile
#------------------------------------------------------------------
#JAVA-JDK-PATH
export JAVA_HOME=/usr/local/jdk
export JAVA_BIN=/usr/local/jdk/bin
export PATH=$PATH:$JAVA_HOME/bin
export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export JAVA_HOME JAVA_BIN PATH CLASSPATH
#------------------------------------------------------------------
[root@localhost ~]# source /etc/profile
[root@localhost ~]# java -version
java version "1.8.0_171"
Java(TM) SE Runtime Environment (build 1.8.0_171-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.171-b11, mixed mode)3.配置MariaDB开启lower_case_table_names选项,每台都要开启.
[root@localhost ~]# yum install -y mariadb mariadb-server
[root@localhost ~]# vim /etc/my.cnf
[mysqld]
lower_case_table_names = 1
[root@localhost ~]# systemctl restart mariadb4.安装zookeeper,其主要用来统计数据.
代码语言：javascript复制[root@localhost ~]# tar -xzvf zookeeper-3.4.12.tar.gz -C /usr/local/
[root@localhost ~]# cd /usr/local/zookeeper-3.4.12/conf/
[root@localhost ~]# cp zoo_sample.cfg zoo.cfg
[root@localhost ~]# vim zoo.cfg
dataDir=/usr/local/...
dataLogDir=/usr/local/...5.运行zookeeper
代码语言：javascript复制[root@localhost ~]# cd /usr/local/zookeeper-3.4.12/bin/
[root@localhost ~]# ./zkServer.sh start
[root@localhost ~]# netstat -ant | grep 2181
tcp 0 0 :::2181 :::* LISTEN
如果出现错误：nohup: failed to run command `java’: No such file or directory
可以在zkServer.sh中的首行添加如下代码
export JAVA_HOME=/usr/lib/jdk
export PATH=$JAVA_HOME/bin:$PATH6.最后一步,安装并运行Mycat-Web
代码语言：javascript复制[root@localhost ~]# tar -xzvf Mycat-web-1.0-SNAPSHOT-20170102153329-linux.tar.gz -C /usr/local
[root@localhost ~]# cd /usr/local/mycat-web
[root@localhost ~]# ./start.sh &
[root@localhost ~]# netstat -an | grep "8082"
tcp 0 0 :::8082 :::* LISTEN
[root@localhost ~]# curl http://localhost:8082/mycat
