Amoeba做为数据库代理,以中间件的形式存在,拓扑图以下所示:(Amoeba官网的一张图)mysql
一、下载Amoeba:https://sourceforge.net/projects/amoeba/files/linux
二、解压并复制到local目录sql
[root@ linux ~]# unzip amoeba-mysql-3.0.5-RC-distribution.zip [root@ linux ~]# cp -rf amoeba-mysql-3.0.5-RC /usr/local
三、启动Amoeba。数据库
[root@chenllcentos ~]# /usr/local/amoeba-mysql-3.0.5-RC/bin/launcher
若是出现fatal exception:centos
The stack size specified is too small, Specify at least 228k Error: Could not create the Java Virtual Machine. Error: A fatal exception has occurred. Program will exit.
缘由是因为stack size过小,致使JVM启动失败,要如何修改呢?bash
解决:服务器
[root@ linux ~]# vi /usr/local/amoeba-mysql-3.0.5-RC/jvm.properties
将内容:app
JVM_OPTIONS="-server -Xms256m -Xmx1024m -Xss196k -XX:PermSize=16m -XX:MaxPermSize=96m"
替换为:jvm
JVM_OPTIONS="-server -Xms1024m -Xmx1024m -Xss256k -XX:PermSize=16m -XX:MaxPermSize=96m"
四、修改配置文件:Amoeba完成读写分离的实现主要是依靠2个很是重要的配置文件:ide
dbServers.xml 和 amoeba.xml
4.一、首先,看看dbServers.xml文件
[root@localhost conf]# cat dbServer.xml
这个文件主要是配置数据库连接,主库,还有从库(slave)节点的信息,以及数据库链接池信息
以下内容就是这个文件的配置
<?xml version="1.0" encoding="gbk"?> <!DOCTYPE amoeba:dbServers SYSTEM “dbserver.dtd”> <amoeba:dbServers xmlns:amoeba=“http://amoeba.meidusa.com/”> <!-- Each dbServer needs to be configured into a Pool, If you need to configure multiple dbServer with load balancing that can be simplified by the following configuration: add attribute with name virtual = "true" in dbServer, but the configuration does not allow the element with name factoryConfig such as 'multiPool' dbServer --> <!-- 该dbServer节点abstractive="true",包含Mysql的公共配置信息,其余dbServer节点都继承该节点 --> <!-- 设置节点配置的继承结构,能够避免重复配置相同信息,减小配置文件冗余 --> <dbServer name="abstractServer" abstractive="true"> <factoryConfig class="com.meidusa.amoeba.mysql.net.MysqlServerConnectionFactory"> <property name="connectionManager">${defaultManager}</property> <property name="sendBufferSize">64</property> <property name="receiveBufferSize">128</property> <!-- mysql port --> <!-- Mysql默认端口 --> <property name="port">3306</property> <!-- mysql schema --> <!-- 默认链接的数据库,若不存在须要事先建立,不然Amoeba启动报错 --> <property name="schema">testdb</property> <!-- mysql user --> <property name="user">root</property> <property name="password">222</property> </factoryConfig> <poolConfig class="com.meidusa.toolkit.common.poolable.PoolableObjectPool"> <property name="maxActive">500</property> <property name="maxIdle">500</property> <property name="minIdle">1</property> <property name="minEvictableIdleTimeMillis">600000</property> <property name="timeBetweenEvictionRunsMillis">600000</property> <property name="testOnBorrow">true</property> <property name="testOnReturn">true</property> <property name="testWhileIdle">true</property> </poolConfig> </dbServer> <!-- Mysql主服务器master节点继承abstractServer --> <dbServer name="master" parent="abstractServer"> <factoryConfig> <!-- master数据库主机地址 --> <property name="ipAddress">192.168.48.133</property> </factoryConfig> </dbServer> <!-- Mysql从服务器slave节点继承abstractServer --> <dbServer name="slave1" parent="abstractServer"> <factoryConfig> <!-- slave数据库主机地址 --> <property name="ipAddress">192.168.48.132</property> </factoryConfig> </dbServer> <!-- 若是有多个从服务器节点, 能够复制多个dbServer --> <!-- 配置数据库读取链接池 Amoeba实现读写分离根据readPool 链接池来实现--> <dbServer name="readPool" virtual="true"> <poolConfig class="com.meidusa.amoeba.server.MultipleServerPool"> <!-- Load balancing strategy: 1=ROUNDROBIN , 2=WEIGHTBASED , 3=HA--> <property name="loadbalance">1</property> <!-- Separated by commas,such as: server1,server2,server1 --> <property name="poolNames">slave1</property> </poolConfig> </dbServer>
配置完成以后:
4.二、接着配置amoeba.xml
vi amoeba.xml
内容以下:
<?xml version="1.0" encoding="gbk"?> <!DOCTYPE amoeba:configuration SYSTEM "amoeba.dtd"> <amoeba:configuration xmlns:amoeba="http://amoeba.meidusa.com/"> <proxy> <!-- service class must implements com.meidusa.amoeba.service.Service --> <service name="Amoeba for Mysql" class="com.meidusa.amoeba.mysql.server.MySQLService"> <!-- port --> <property name="port">8066</property> <!-- bind ipAddress --> <!-- <property name="ipAddress">127.0.0.1</property> --> <property name="connectionFactory"> <bean class="com.meidusa.amoeba.mysql.net.MysqlClientConnectionFactory"> <property name="sendBufferSize">128</property> <property name="receiveBufferSize">64</property> </bean> </property> <property name="authenticateProvider"> <bean class="com.meidusa.amoeba.mysql.server.MysqlClientAuthenticator"> <property name="user">root</property> <property name="password"></property> <property name="filter"> <bean class="com.meidusa.toolkit.net.authenticate.server.IPAccessController"> <property name="ipFile">${amoeba.home}/conf/access_list.conf</property> </bean> </property> </bean> </property> </service> <runtime class="com.meidusa.amoeba.mysql.context.MysqlRuntimeContext"> <!-- proxy server client process thread size --> <property name="executeThreadSize">128</property> <!-- per connection cache prepared statement size --> <property name="statementCacheSize">500</property> <!-- default charset --> <property name="serverCharset">utf8</property> <!-- query timeout( default: 60 second , TimeUnit:second) --> <property name="queryTimeout">60</property> </runtime> </proxy> <!-- Each ConnectionManager will start as thread manager responsible for the Connection IO read , Death Detection --> <connectionManagerList> <connectionManager name="defaultManager" class="com.meidusa.toolkit.net.MultiConnectionManagerWrapper"> <property name="subManagerClassName">com.meidusa.toolkit.net.AuthingableConnectionManager</property> </connectionManager> </connectionManagerList> <!-- default using file loader --> <dbServerLoader class="com.meidusa.amoeba.context.DBServerConfigFileLoader"> <property name="configFile">${amoeba.home}/conf/dbServers.xml</property> </dbServerLoader> <queryRouter class="com.meidusa.amoeba.mysql.parser.MysqlQueryRouter"> <property name="ruleLoader"> <bean class="com.meidusa.amoeba.route.TableRuleFileLoader"> <property name="ruleFile">${amoeba.home}/conf/rule.xml</property> <property name="functionFile">${amoeba.home}/conf/ruleFunctionMap.xml</property> </bean> </property> <property name="sqlFunctionFile">${amoeba.home}/conf/functionMap.xml</property> <property name="LRUMapSize">1500</property> <property name="defaultPool">multiPool</property> <!-- <property name="writePool">server1</property> <property name="readPool">server1</property> --> <property name="needParse">true</property> </queryRouter> </amoeba:configuration>
咱们须要改的有3个地方:
五、启动
cd /usr/local/amoeba-mysql-3.0.5-RC/bin/ ./launcher
出现以下信息就是启动成功了
2016-10-11 23:20:55 [INFO] Project Name=Amoeba-MySQL, PID=4097 , System shutdown .... 2016-10-11 23:27:49 [INFO] Project Name=Amoeba-MySQL, PID=4162 , starting... log4j:WARN log4j config load completed from file:/usr/local/amoeba-mysql-3.0.5-RC/conf/log4j.xml 2016-10-11 23:27:50,736 INFO context.MysqlRuntimeContext - Amoeba for Mysql current versoin=5.1.45-mysql-amoeba-proxy-3.0.4-BETA log4j:WARN ip access config load completed from file:/usr/local/amoeba-mysql-3.0.5-RC/conf/access_list.conf 2016-10-11 23:27:51,863 INFO net.ServerableConnectionManager - Server listening on 0.0.0.0/0.0.0.0:8066.
六、测试
先中止从库的主从复制
mysql>slave stop;
查询主库的数据
mysql> select * from t_test; +------+------+ | id | name | +------+------+ | 3 | t3 | +------+------+
查询从库的数据
mysql> select * from t_test; +------+------+ | id | name | +------+------+ | 1 | aaa | +------+------+
登陆Amoeba
mysql -uroot -p111111 -h192.168.48.133 -P8066
先使用查询语句
-- 通过屡次测试查询,始终返回从库的数据 mysql> select * from t_test ; +------+------+ | id | name | +------+------+ | 1 | aaa | +------+------+ 1 row in set (0.00 sec)
再使用insert语句
mysql> insert into t_test (id,name) values (100,'100'); Query OK, 1 row affected (0.02 sec) mysql> insert into t_test (id,name) values (200,'200'); Query OK, 1 row affected (0.00 sec)
如今看看insert语句的结果:
-- 查询从库的结果: mysql> select * from t_test; +------+------+ | id | name | +------+------+ | 100 | 100 | | 200 | 200 | +------+------+
-- 查询主库的结果 mysql> select * from t_test; +------+------+ | id | name | +------+------+ | 200 | 200 | | 100 | 100 | +------+------+ 2 rows in set (0.00 sec)
--在Amoeba执行查询的结果: mysql> select * from t_test ; +------+------+ | id | name | +------+------+ | 100 | 100 | | 200 | 200 | +------+------+ 2 rows in set (0.07 sec)
已经成功了。。。查询操做,始终查询的是从库的数据,而insert操做,始终是对主库进行操做
JAVA程序中整合amoeba的话,只须要把数据库连接改为amoeba的就好了。。
在企业的实际项目中,这样作的好处是,不须要对代码进行硬编码,具有很是高的解耦做用,并且,Amoeba的配置也很是的简单,其实还有分库和分表的操做,这里就不作演示
amoeba里查询的时候报错: amoeba ERROR 1044 (42000): Could not create a validated object, cause: ValidateObject failed
这个问题,我在网上找到了一个缘由,就是,amoeba去从库查询的时候,帐号没权限。grant 赋予从库那个帐号全部权限就行了。