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Amoeba+Mysql实现数据库读写分离

一、Amoeba 是什么

Amoeba(变形虫)项目,专注 分布式数据库 proxy 开发。座落与Client、DB Server(s)之间。对客户端透明。具有负载均衡、高可用性、sql过滤、读写分离、可路由相关的query到目标数据库、可并发请求多台数据库合并结果。

主要解决:

? 降低 数据切分带来的复杂多数据库结构

? 提供切分规则并降低 数据切分规则 给应用带来的影响

? 降低db 与客户端的连接数

? 读写分离

 

二、为什么要用Amoeba

目前要实现mysql的主从读写分离,主要有以下几种方案:

1、  通过程序实现,网上很多现成的代码,比较复杂,如果添加从服务器要更改多台服务器的代码。

2、  通过mysql-proxy来实现,由于mysql-proxy的主从读写分离是通过lua脚本来实现,目前lua的脚本的开发跟不上节奏,而写没有完美的现成的脚本,因此导致用于生产环境的话风险比较大,据网上很多人说mysql-proxy的性能不高。

3、  自己开发接口实现,这种方案门槛高,开发成本高,不是一般的小公司能承担得起。

4、  利用阿里巴巴的开源项目Amoeba来实现,具有负载均衡、高可用性、sql过滤、读写分离、可路由相关的query到目标数据库,并且安装配置非常简单。国产的开源软件,应该支持,目前正在使用,不发表太多结论,一切等测试完再发表结论吧,哈哈!

 

三、Amoeba的安装

先介绍下部署环境:

amoeba:192.168.2.203

masterDB:192.168.2.204 

slaveDB:192.168.2.205

以上系统全为centos6.8

 

Amoeba框架是居于JDK1.5开发的,采用了JDK1.5的特性,所以还需要安装java环境,建议使用javaSE1.5以上的JDK版本

1、安装java环境

先去官网下载:http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

安装

[root@bogon src]# rpm -ivh jdk-8u111-linux-x64.rpm
Preparing...                ########################################### [100%]
   1:jdk1.8.0_111           ########################################### [100%]
Unpacking JAR files...
    tools.jar...
    plugin.jar...
    javaws.jar...
    deploy.jar...
    rt.jar...
    jsse.jar...
    charsets.jar...
    localedata.jar...

然后设置java环境变量

[root@bogon src]# vim /etc/profile

#set java environment
JAVA_HOME=/usr/java/jdk1.8.0_111
JRE_HOME=/usr/java/jdk1.8.0_111/jre
CLASS_PATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/lib
PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
export JAVA_HOME JRE_HOME CLASS_PATH PATH
[root@bogon amoeba]# source /etc/profile

测试是否安装成功

[root@bogon src]# java -version
java version "1.8.0_111"
Java(TM) SE Runtime Environment (build 1.8.0_111-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.111-b14, mixed mode)

2、安装Amoeba

可以从https://sourceforge.net/projects/amoeba/下载最新版本的Amoeba,我这里下载的是amoeba-mysql-3.0.5-RC-distribution.zip。Amoeba安装非常简单,直接解压即可使用,这里将Amoeba解压到/usr/local/amoeba目录下,这样就安装完成了

[root@bogon amoeba]# pwd
/usr/local/amoeba

  [root@bogon amoeba]# ll
  总用量 20
  drwxrwxrwx. 2 root root 4096 7月 5 2013 benchmark
  drwxrwxrwx. 2 root root 4096 7月 5 2013 bin
  drwxrwxrwx. 2 root root 4096 7月 5 2013 conf
  -rwxrwxrwx. 1 root root 728 7月 5 2013 jvm.properties
  drwxrwxrwx. 2 root root 4096 7月 5 2013 lib

 

3、配置Amoeba

Amoeba的配置文件在本环境下位于/usr/local/amoeba/conf目录下。配置文件比较多,但是仅仅使用读写分离功能,只需配置两个文件即可,分别是dbServers.xml和amoeba.xml,如果需要配置ip访问控制,还需要修改access_list.conf文件,下面首先介绍dbServers.xml

[root@bogon amoeba]# cat conf/dbServers.xml 
<?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   
        -->
        
    <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 -->
            <property name="port">3306</property>  #设置Amoeba要连接的mysql数据库的端口,默认是3306
            
            <!-- mysql schema -->
            <property name="schema">testdb</property>  #设置缺省的数据库,当连接amoeba时,操作表必须显式的指定数据库名,即采用dbname.tablename的方式,不支持 use dbname指定缺省库,因为操作会调度到各个后端dbserver
            
            <!-- mysql user -->
            <property name="user">test1</property>  #设置amoeba连接后端数据库服务器的账号和密码,因此需要在所有后端数据库上创建该用户,并授权amoeba服务器可连接
            
            <property name="password">111111</property>
        </factoryConfig>

        <poolConfig class="com.meidusa.toolkit.common.poolable.PoolableObjectPool">
            <property name="maxActive">500</property>  #最大连接数,默认500
            <property name="maxIdle">500</property>    #最大空闲连接数
            <property name="minIdle">1</property>    #最新空闲连接数
            <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>

    <dbServer name="writedb"  parent="abstractServer">  #设置一个后端可写的dbServer,这里定义为writedb,这个名字可以任意命名,后面还会用到
        <factoryConfig>
            <!-- mysql ip -->
            <property name="ipAddress">192.168.2.204</property> #设置后端可写dbserver
        </factoryConfig>
    </dbServer>
    
    <dbServer name="slave"  parent="abstractServer">  #设置后端可读dbserver
        <factoryConfig>
            <!-- mysql ip -->
            <property name="ipAddress">192.168.2.205</property>
        </factoryConfig>
    </dbServer>
    
    <dbServer name="myslave" virtual="true">  #设置定义一个虚拟的dbserver,实际上相当于一个dbserver组,这里将可读的数据库ip统一放到一个组中,将这个组的名字命名为myslave
        <poolConfig class="com.meidusa.amoeba.server.MultipleServerPool">
            <!-- Load balancing strategy: 1=ROUNDROBIN , 2=WEIGHTBASED , 3=HA-->
            <property name="loadbalance">1</property>  #选择调度算法,1表示复制均衡,2表示权重,3表示HA, 这里选择1
            
            <!-- Separated by commas,such as: server1,server2,server1 -->
            <property name="poolNames">slave</property>  #myslave组成员
        </poolConfig>
    </dbServer>
        
</amoeba:dbServers>

 

另一个配置文件amoeba.xml

[root@bogon amoeba]# cat conf/amoeba.xml 
<?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>    #设置amoeba监听的端口,默认是8066
            
            <!-- bind ipAddress -->    #下面配置监听的接口,如果不设置,默认监听所以的IP
            <!-- 
            <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">
                    
  1. # 提供客户端连接amoeba时需要使用这里设定的账号 (这里的账号密码和amoeba连接后端数据库服务器的密码无关)
                    <property name="user">root</property>    
<property name="password">123456</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">writedb</property>  #设置amoeba默认的池,这里设置为writedb <property name="writePool">writedb</property>  #这两个选项默认是注销掉的,需要取消注释,这里用来指定前面定义好的俩个读写池 <property name="readPool">myslave</property>   # <property name="needParse">true</property> </queryRouter> </amoeba:configuration>

4、在masterdb上创建数据库testdb

mysql> create database testdb;
Query OK, 1 row affected (0.08 sec)

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mydb               |
| mysql              |
| performance_schema |
| test               |
| testdb             |
+--------------------+
6 rows in set (0.00 sec)

查看slavedb是否复制成功

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mydb               |
| mysql              |
| performance_schema |
| test               |
| testdb             |
+--------------------+
6 rows in set (0.00 sec)

分别在masterdb和slavedb上为amoedb授权

 

mysql> GRANT ALL ON testdb.* TO test1@192.168.2.203 IDENTIFIED BY 111111;
Query OK, 0 rows affected (0.05 sec)

mysql> flush privileges;
Query OK, 0 rows affected (0.02 sec)

启动amoeba

[root@bogon amoeba]# /usr/local/amoeba/bin/launcher
Error: JAVA_HOME environment variable is not set.
[root@bogon amoeba]# vim /etc/profile^C
[root@bogon amoeba]# source /etc/profile
[root@bogon amoeba]# /usr/local/amoeba/bin/launcher
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option PermSize=16m; support was removed in 8.0
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option MaxPermSize=96m; support was removed in 8.0

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.

报错:

Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.

从错误文字上看,应该是由于stack size太小,导致JVM启动失败,要如何修改呢?
其实Amoeba已经考虑到这个问题,并将JVM参数配置写在属性文件里。现在,让我们通过该属性文件修改JVM参数。
修改jvm.properties文件JVM_OPTIONS参数。

[root@bogon amoeba]# vim /usr/local/amoeba/jvm.properties 
改成:JVM_OPTIONS="-server -Xms1024m -Xmx1024m -Xss256k -XX:PermSize=16m -XX:MaxPermSize=96m"
原为:JVM_OPTIONS="-server -Xms256m -Xmx1024m -Xss196k -XX:PermSize=16m -XX:MaxPermSize=96m"

再次启动

[root@bogon ~]# /usr/local/amoeba/bin/launcher
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchStandard(Launcher.java:329)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:239)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:409)
    at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:127)
    at org.codehaus.classworlds.Launcher.main(Launcher.java:110)
Caused by: com.meidusa.toolkit.common.bean.util.InitialisationException: default pool required!,defaultPool=writedb invalid
    at com.meidusa.amoeba.route.AbstractQueryRouter.init(AbstractQueryRouter.java:469)
    at com.meidusa.amoeba.context.ProxyRuntimeContext.initAllInitialisableBeans(ProxyRuntimeContext.java:337)
    ... 11 more
 2016-10-24 18:46:37 [INFO] Project Name=Amoeba-MySQL, PID=1577 , System shutdown ....
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option PermSize=16m; support was removed in 8.0
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option MaxPermSize=96m; support was removed in 8.0
 2016-10-24 18:50:19 [INFO] Project Name=Amoeba-MySQL, PID=1602 , starting...
log4j:WARN log4j config load completed from file:/usr/local/amoeba/conf/log4j.xml
2016-10-24 18:50:21,668 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/conf/access_list.conf
2016-10-24 18:50:22,852 INFO  net.ServerableConnectionManager - Server listening on 0.0.0.0/0.0.0.0:8066.

查看端口

[root@bogon ~]# netstat -unlpt | grep java
tcp        0      0 :::8066                     :::*                        LISTEN      1602/java    

由此可知Amoeba启动正常

 

5、测试

远程登陆mysql客户端通过指定amoeba配置文件中指定的用户名、密码、和端口以及amoeba服务器ip地址链接mysql数据库

[root@lys2 ~]# mysql -h192.168.2.203 -uroot -p -P8066
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1364055863
Server version: 5.1.45-mysql-amoeba-proxy-3.0.4-BETA Source distribution

Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.

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> 

在testdb中创建表test并插入数据

mysql> use testdb;
Database changed
mysql> create table test_table(id int,password varchar(40) not null);
Query OK, 0 rows affected (0.19 sec)

mysql> show tables;
+------------------+
| Tables_in_testdb |
+------------------+
| test_table       |
+------------------+
1 row in set (0.02 sec)

mysql> insert into test_table(id,password) values(1,test1);
Query OK, 1 row affected (0.04 sec)

mysql> select * from test_table;
+------+----------+
| id   | password |
+------+----------+
|    1 | test1    |
+------+----------+
1 row in set (0.02 sec)

分别登陆masterdb和slavedb查看数据

masterdb:

mysql> use testdb;
Database changed
mysql> show tables;
+------------------+
| Tables_in_testdb |
+------------------+
| test_table       |
+------------------+
1 row in set (0.00 sec)

mysql> select * from test_table;
+------+----------+
| id   | password |
+------+----------+
|    1 | test1    |
+------+----------+
1 row in set (0.03 sec)

slavedb:

mysql> use testdb;
Database changed
mysql> show tables;
+------------------+
| Tables_in_testdb |
+------------------+
| test_table       |
+------------------+
1 row in set (0.00 sec)

mysql> select * from test_table;
+------+----------+
| id   | password |
+------+----------+
|    1 | test1    |
+------+----------+
1 row in set (0.00 sec)

停掉masterdb,然后在客户端分别执行插入和查询功能

masterdb:

  [root@bogon ~]# service mysqld stop
  Shutting down MySQL. SUCCESS!

客户端:

mysql> insert into test_table(id,password) values(2,test2);
ERROR 1044 (42000): Amoeba could not connect to MySQL server[192.168.2.204:3306],拒绝连接
mysql> select * from test_table;
+------+----------+
| id   | password |
+------+----------+
|    1 | test1    |
+------+----------+
1 row in set (0.01 sec)

可以看到,关掉masterdb和写入报错,读正常

开启masterdb上的msyql 关闭slave上的mysql

masterdb:

[root@bogon ~]# service mysqld start
Starting MySQL.. SUCCESS! 

slavedb:

[root@localhost ~]# service mysqld stop
Shutting down MySQL. SUCCESS! 

客户端再次尝试

mysql> insert into test_table(id,password) values(2,test2);
Query OK, 1 row affected (0.19 sec)

mysql> select * from test_table;
ERROR 1044 (42000): poolName=myslave, no valid pools

可以看到插入成功,读取失败

 

开启slavedb上的mysql,查看数据是否自动同步

slavedb:

[root@localhost ~]# service mysqld start
Starting MySQL... SUCCESS! 

客户端:

mysql> select * from test_table;
+------+----------+
| id   | password |
+------+----------+
|    1 | test1    |
|    2 | test2    |
+------+----------+
2 rows in set (0.01 sec)

接着客户端:

mysql> insert into test_table(id,password) values(3,test3);
Query OK, 1 row affected (0.03 sec)

mysql> select * from test_table;
+------+----------+
| id   | password |
+------+----------+
|    1 | test1    |
|    2 | test2    |
|    3 | test3    |
+------+----------+
3 rows in set (0.02 sec)

OK 一切正常,到此全部结束

 

注:关于mysql主从同步自行查看博主之前的主从同步笔记!

 

Amoeba+Mysql实现数据库读写分离