一、MySQL 5.6介绍
MySQL 5.6引入的GTID(Global Transaction IDs)使得其复制功能的配置、监控及管理变得更加易于实现,且更加健壮。
复制功能的改进:
1、支持多线程复制,指的是针对每个database开启相应的独立线程。
2、支持启用GTID,就是每个mysql服务器都一个全局的事务ID,GTID,这个是由每个服务器的UUID(唯一的)和server_id组成的,mysql会保证事务与GTID之间1:1的映射,保证了GTID的全局唯一性。
二、Amoeba介绍
Amoeba是一个SQL请求的路由器,可以为mysql提供负载均衡、读写分离、高可用性提供机制,用户需要结合使用MySQL的Replication等机制来实现副本同步等功能,它主要在应用层访问MySQL的时候充当query 路由功能,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,它是一个虚拟的mysql,对外提供mysql协议,客户端连接amoeba就象连接mysql一样。
Amoeba主要优势:
1、数据切分后复杂数据源整合;
2、提供数据切分规则并降低数据切分规则给数据库带来的影响;
3、降低数据库与客户端连接;
4、读写分离路由。
Amoeba不足:
1、不支持事务;
2、不支持存储过程;
3、不适合从amoeba导数据的场景或者对大数据量查询的query并不合适;
4、不支持分库分表,amoeba只支持分数据库实例,每个被切分的节点需要保持库表结构一致。
三、实验环境
192.168.30.115 OS:CentOS 6.4 x86_64 amoeba.luojianlong.com
192.168.30.116 OS:CentOS 6.4 x86_64 master.luojianlong.com
192.168.30.117 OS:CentOS 6.4 x86_64 slave.luojianlong.com
MySQL version:mysql-5.6.13-linux-glibc2.5-x86_64
Amoeba version:amoeba-mysql-binary-2.1.0-RC5
拓扑图如下:
首先,分别在master.luojianlong.com和slave.luojianlong.com上安装mysql 5.6.13,这里使用通用的二进制包来安装
[root@master ~]# useradd -r -u 27 mysql [root@master ~]# tar zxvf mysql-5.6.13-linux-glibc2.5-x86_64.tar.gz -C /usr/local/ [root@master ~]# cd /usr/local/ [root@master local]# ln -s mysql-5.6.13-linux-glibc2.5-x86_64 mysql [root@master local]# ln -s mysql-5.6.13-linux-glibc2.5-x86_64 mysql [root@master local]# cd mysql [root@master mysql]# mkdir /mydata/data -p [root@master mysql]# chown -R root.mysql ./* [root@master mysql]# chown -R mysql.mysql /mydata/data/ [root@master mysql]# ./scripts/mysql_install_db --user=mysql --datadir=/mydata/data [root@master mysql]# cp support-files/mysql.server /etc/rc.d/init.d/mysqld [root@master mysql]# chkconfig --add mysqld [root@master mysql]# chkconfig mysqld on [root@master mysql]# chmod +x /etc/rc.d/init.d/mysqld [root@master ~]# vi /etc/profile.d/mysql.sh export PATH=/usr/local/mysql/bin:$PATH [root@master ~]# . /etc/profile.d/mysql.sh # 由于mysql 5.6版本默认的配置文件配置参数很少,需要自己定制,为了方便,这里使用mysql 5.5的配置文件 [root@master mysql]# cp my-large.cnf /etc/my.cnf [root@master mysql]# vi /etc/my.cnf # 在[mysqld]中添加如下 datadir = /mydata/data innodb_file_per_table = 1 binlog-format=ROW log-bin=master-bin log-slave-updates=true gtid-mode=on enforce-gtid-consistency=true master-info-repository=TABLE relay-log-info-repository=TABLE sync-master-info=1 slave-parallel-workers=2 binlog-checksum=CRC32 master-verify-checksum=1 slave-sql-verify-checksum=1 binlog-rows-query-log_events=1 server-id=1 report-port=3306 port=3306 report-host=192.168.30.116
在slave.luojianlong.com中也使用相同的方式安装mysql 5.6
# 安装完成后,修改配置文件 [root@slave ~]# vi /etc/my.cnf # 添加如下 datadir = /mydata/data innodb_file_per_table = 1 binlog-format=ROW log-slave-updates=true gtid-mode=on enforce-gtid-consistency=true master-info-repository=TABLE relay-log-info-repository=TABLE sync-master-info=1 slave-parallel-workers=2 binlog-checksum=CRC32 master-verify-checksum=1 slave-sql-verify-checksum=1 binlog-rows-query-log_events=1 server-id=11 report-port=3306 port=3306 log-bin=mysql-bin.log datadir=/mydata/data report-host=192.168.30.117
binlog-format:二进制日志的格式,有row、statement和mixed几种类型;
需要注意的是:当设置隔离级别为READ-COMMITED必须设置二进制日志格式为ROW,现在MySQL官方认为STATEMENT这个已经不再适合继续使用;但mixed类型在默认的事务隔离级别下,可能会导致主从数据不一致;
log-slave-updates、gtid-mode、enforce-gtid-consistency、report-port和report-host:用于启动GTID及满足附属的其它需求;
master-info-repository和relay-log-info-repository:启用此两项,可用于实现在崩溃时保证二进制及从服务器安全的功能;
sync-master-info:启用之可确保无信息丢失;
slave-paralles-workers:设定从服务器的SQL线程数;0表示关闭多线程复制功能;
binlog-checksum、master-verify-checksum和slave-sql-verify-checksum:启用复制有关的所有校验功能;
binlog-rows-query-log-events:启用之可用于在二进制日志记录事件相关的信息,可降低故障排除的复杂度;
log-bin:启用二进制日志,这是保证复制功能的基本前提;
server-id:同一个复制拓扑中的所有服务器的id号必须惟一;
分别启动俩台服务器的mysql
[root@master ~]# service mysqld start Starting MySQL............ SUCCESS! [root@slave ~]# service mysqld start Starting MySQL... SUCCESS!
在master服务器上创建复制用户
mysql> grant replication slave on *.* to 'repluser'@'192.168.30.%' identified by '123456'; Query OK, 0 rows affected (0.06 sec) mysql> flush privileges; Query OK, 0 rows affected (0.00 sec)
启动从节点的复制线程
mysql> change master to master_host='192.168.30.116', master_user='repluser', master_password='123456', master_auto_position=1; Query OK, 0 rows affected, 2 warnings (0.45 sec) mysql> start slave; Query OK, 0 rows affected, 1 warning (0.12 sec)
在slave上查看线程启动情况
mysql> show slave status\G; *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 192.168.30.116 Master_User: repluser Master_Port: 3306 Connect_Retry: 60 Master_Log_File: master-bin.000002 Read_Master_Log_Pos: 539 Relay_Log_File: slave-relay-bin.000002 Relay_Log_Pos: 751 Relay_Master_Log_File: master-bin.000002 Slave_IO_Running: Yes Slave_SQL_Running: Yes Replicate_Do_DB: Replicate_Ignore_DB: Replicate_Do_Table: Replicate_Ignore_Table: Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0 Last_Error: Skip_Counter: 0 Exec_Master_Log_Pos: 539 Relay_Log_Space: 955 Until_Condition: None Until_Log_File: Until_Log_Pos: 0 Master_SSL_Allowed: No Master_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: 0 Master_SSL_Verify_Server_Cert: No Last_IO_Errno: 0 Last_IO_Error: Last_SQL_Errno: 0 Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 1 Master_UUID: b05c9b5c-bfac-11e3-a4bc-000c29f3fcba Master_Info_File: mysql.slave_master_info SQL_Delay: 0 SQL_Remaining_Delay: NULL Slave_SQL_Running_State: Slave has read all relay log; waiting for the slave I/O thread to update it Master_Retry_Count: 86400 Master_Bind: Last_IO_Error_Timestamp: Last_SQL_Error_Timestamp: Master_SSL_Crl: Master_SSL_Crlpath: Retrieved_Gtid_Set: b05c9b5c-bfac-11e3-a4bc-000c29f3fcba:1-2 Executed_Gtid_Set: b05c9b5c-bfac-11e3-a4bc-000c29f3fcba:1-2 Auto_Position: 1 1 row in set (0.00 sec)
Connect_Retry:slave服务器连接master服务器的重试次数;
Exec_Master_Log_Pos:当前slave服务器最后一次所执行二进制日志的位置;
Relay_Log_Space:relaylog的空间;
Seconds_Behind_Master:slave滞后master的时长(通过当前服务器的时间戳与二进制日志中的时间戳对比得到的);
Slave_IO_Running:slave服务器I/O线程的运行情况;
Slave_SQL_Running:slave服务器SQL线程的运行情况;
发现gtid复制已经启动成功,并可以查看主从服务器的uuid(对于每一个mysql服务器都是唯一的)
mysql> show global variables like '%uuid'; +---------------+--------------------------------------+ | Variable_name | Value | +---------------+--------------------------------------+ | server_uuid | b05c9b5c-bfac-11e3-a4bc-000c29f3fcba | +---------------+--------------------------------------+ 1 row in set (0.00 sec) mysql> show global variables like '%uuid'; +---------------+--------------------------------------+ | Variable_name | Value | +---------------+--------------------------------------+ | server_uuid | ba83181a-bfac-11e3-a4bc-000c295b50f9 | +---------------+--------------------------------------+ 1 row in set (0.00 sec)
在slave 可以看到启动的复制线程数
mysql> show processlist; +-----+-------------+-----------+------+---------+-------+-----------------------------------------------------------------------------+------------------+ | Id | User | Host | db | Command | Time | State | Info | +-----+-------------+-----------+------+---------+-------+-----------------------------------------------------------------------------+------------------+ | 3 | system user | | NULL | Connect | 67092 | Waiting for master to send event | NULL | | 4 | system user | | NULL | Connect | 50955 | Slave has read all relay log; waiting for the slave I/O thread to update it | NULL | | 5 | system user | | NULL | Connect | 65267 | Waiting for an event from Coordinator | NULL | | 6 | system user | | NULL | Connect | 50961 | Waiting for an event from Coordinator | NULL | | 151 | root | localhost | NULL | Query | 0 | init | show processlist | +-----+-------------+-----------+------+---------+-------+-----------------------------------------------------------------------------+------------------+ 5 rows in set (0.00 sec)
在master创建数据库,看是否同步到slave
mysql> create database student; Query OK, 1 row affected (0.01 sec) mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | abc | | mysql | | performance_schema | | student | | test | | testdb | +--------------------+ 7 rows in set (0.00 sec)
发现已经同步到slave
主从服务器数据不一致的常见原因:
1、在slave服务器上直接执行写操作;
2、基于SQL语句的复制,建议使用基于数据本身的复制;
3、relaylog日志出现故障;
4、数据库架构复制有问题;
5、在一个数据库里面混合使用myisam和innodb引擎;
6、mysql的主从版本不一致(从服务器的版本必须高于主服务器版本);
7、使用myisam存储引擎时,执行的语句被意外终止;
修复主从服务器数据不一致的方案:
1、使用pt-table-checksum工具,能够监控主从服务器数据表中的数据是否一致;
2、使用pt-table-sync工具,能够实现同步主从服务器上表的数据;
防止主从复制崩溃后带来的损失:
1、设置master服务器的sync_binlog=1,意思是只要有数据更新就立即同步到磁盘上面,同时要求磁盘本身不具有缓存能力;
2、使用innodb存储引擎时,当slave服务器意外关闭后,重新启动会重新读取master_info文件,这个时候master_info数据没刷新到磁盘上面,这样会导致数据复制出现错误,这个时候可以在slave上启用innodb_overwrite_relay_log_info;可以覆盖relay_log_info里面的数据,避免造成数据丢失;
3、或者也可以使用工具pt-slave-restart,从节点意外关闭时,用于安全启动复制进程;
4、当master服务器二进制日志出现错误时,可以在slave服务器上执行set global sql_slave_skip_counter=1;start slave; 跳过错误,或者删除二进制日志重新生成,然后重新建立复制;
下面开始配置amoeba,首先安装jdk环境
[root@amoeba ~]# tar zxvf jdk-7u25-linux-x64.gz -C /usr/local/ [root@amoeba ~]# cd /usr/local/ [root@amoeba local]# ln -s jdk1.7.0_25 jdk [root@amoeba local]# vi /etc/profile.d/jdk.sh export JAVA_HOME=/usr/local/jdk export CLASSPATH=$CLASSPATH:$JAVA_HOME/lib:$JAVA_HOME/jre/lib export PATH=/usr/local/jdk/bin:$PATH [root@amoeba local]# . /etc/profile.d/jdk.sh [root@amoeba local]# java -version java version "1.7.0_25" Java(TM) SE Runtime Environment (build 1.7.0_25-b15) Java HotSpot(TM) 64-Bit Server VM (build 23.25-b01, mixed mode)
下载安装amoeba
[root@amoeba ~]# mkdir /usr/local/amoeba [root@amoeba ~]# tar zxvf amoeba-mysql-binary-2.1.0-RC5.tar.gz -C /usr/local/amoeba/ [root@amoeba ~]# vi /etc/profile.d/amoeba.sh export PATH=/usr/local/amoeba/bin:$PATH [root@amoeba ~]# . /etc/profile.d/amoeba.sh [root@amoeba ~]# cp /usr/local/amoeba/conf/amoeba.xml /usr/local/amoeba/conf/amoeba.xml.bak [root@amoeba ~]# cp /usr/local/amoeba/conf/dbServers.xml /usr/local/amoeba/conf/dbServers.xml.bak
调整amoeba配置文件,设置读写分离
[root@amoeba ~]# vi /usr/local/amoeba/conf/amoeba.xml # 在子标签中修改如下几项 3306 0.0.0.0 mypass # 在子标签中启用修改下面几项 server1 server2 [root@amoeba ~]# vi /usr/local/amoeba/conf/dbServers.xml # 启动并修改子标签中的 mypass # 修改子标签中的 192.168.30.116 # 新添加一个dbServer如下192.168.30.117
在master和slave中分别创建用于amoeba连接俩台mysql的用户
# 在master上面创建 mysql> grant all on *.* to 'root'@'192.168.30.%' identified by 'mypass'; Query OK, 0 rows affected (0.00 sec) mysql> flush privileges; Query OK, 0 rows affected (0.00 sec) #发现已经同步到slave mysql> show grants for 'root'@'192.168.30.%'; +-------------------------------------------------------------------------------------------------------------------------+ | Grants for [email protected].% | +-------------------------------------------------------------------------------------------------------------------------+ | GRANT ALL PRIVILEGES ON *.* TO 'root'@'192.168.30.%' IDENTIFIED BY PASSWORD '*6C8989366EAF75BB670AD8EA7A7FC1176A95CEF4' | +-------------------------------------------------------------------------------------------------------------------------+ 1 row in set (0.00 sec)
启动amoeba
[root@amoeba ~]# vi /usr/local/amoeba/bin/amoeba DEFAULT_OPTS="-server -Xms256m -Xmx256m -Xss128k" # 修改为 DEFAULT_OPTS="-server -Xms256m -Xmx256m -Xss256k" [root@amoeba ~]# amoeba start log4j:WARN log4j config load completed from file:/usr/local/amoeba/conf/log4j.xml 2014-04-09 15:09:15,121 INFO context.MysqlRuntimeContext - Amoeba for Mysql current versoin=5.1.45-mysql-amoeba-proxy-2.1.0-RC5 log4j:WARN ip access config load completed from file:/usr/local/amoeba/conf/access_list.conf 2014-04-09 15:09:15,482 INFO net.ServerableConnectionManager - Amoeba for Mysql listening on /0.0.0.0:3306. 2014-04-09 15:09:15,489 INFO net.ServerableConnectionManager - Amoeba Monitor Server listening on /127.0.0.1:53201. [root@amoeba ~]# netstat -anptl | grep :3306 tcp 0 0 :::3306 :::* LISTEN 19208/java tcp 0 0 ::ffff:192.168.30.115:33408 ::ffff:192.168.30.116:3306 ESTABLISHED 19208/java tcp 0 0 ::ffff:192.168.30.115:59880 ::ffff:192.168.30.117:3306 ESTABLISHED 19208/java [root@amoeba ~]# mysql -u root -pmypass -h 192.168.30.115 -P 3306 Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 1783342624 Server version: 5.1.45-mysql-amoeba-proxy-2.1.0-RC5 MySQL Community Server (GPL) Copyright (c) 2000, 2012, 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> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | performance_schema | | test | +--------------------+ 4 rows in set (0.03 sec)
启动成功,并访问正常
下面使用tcpdump命令抓包测试读写分离效果
[root@master ~]# tcpdump -i eth0 -s0 -nn -A tcp dst port 3306 and dst host 192.168.30.116 [root@slave ~]# tcpdump -i eth0 -s0 -nn -A tcp dst port 3306 and dst host 192.168.30.117 # amoeba服务器上登录mysql,并创建数据库 mysql> create database abc; Query OK, 1 row affected (0.03 sec) [root@master ~]# tcpdump -i eth0 -s0 -nn -A tcp dst port 3306 and dst host 192.168.30.116 tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes 15:16:42.492828 IP 192.168.30.115.33408 > 192.168.30.116.3306: Flags [P.], seq 1149949367:1149949391, ack 113323290, win 123, options [nop,nop,TS val 8373727 ecr 10837334], length 24 E..L&"@[email protected]....{4]..... ......]V.....create database abc 15:16:42.501837 IP 192.168.30.115.33408 > 192.168.30.116.3306: Flags [.], ack 12, win 123, options [nop,nop,TS val 8373736 ecr 11221763], length 0 E..4@[email protected]%...{.I..... ......;. 15:16:42.502356 IP 192.168.30.117.38626 > 192.168.30.116.3306: Flags [.], ack 3194819787, win 170, options [nop,nop,TS val 9637577 ecr 11221763], length 0 E..4.0@[email protected]............. ......;. # 发现在master上面抓到了创建数据库的包 [root@slave ~]# tcpdump -i eth0 -s0 -nn -A tcp dst port 3306 and dst host 192.168.30.117 tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes # slave上面没有抓到任何包 # 下面在amoeba上面执行创建表,插入,查询语句 mysql> use abc Database changed mysql> create table test(id int); Query OK, 0 rows affected (0.41 sec) mysql> insert into test values(1); Query OK, 1 row affected (0.04 sec) mysql> select * from test; +------+ | id | +------+ | 1 | +------+ 1 row in set (0.01 sec) [root@master ~]# tcpdump -i eth0 -s0 -nn -A tcp dst port 3306 and dst host 192.168.30.116 tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes 15:20:42.054548 IP 192.168.30.115.33419 > 192.168.30.116.3306: Flags [P.], seq 976065559:976065590, ack 2591052457, win 123, options [nop,nop,TS val 8613289 ecr 11418139], length 31 E..S."@[email protected]....:-...pR....{.H..... ..m...:......insert into test values(1) 15:20:42.085305 IP 192.168.30.117.38626 > 192.168.30.116.3306: Flags [.], ack 3194820258, win 189, options [nop,nop,TS val 9877161 ecr 11461346], length 0 E..4.2@[email protected].......*..... ........ 15:20:42.086686 IP 192.168.30.115.33419 > 192.168.30.116.3306: Flags [.], ack 12, win 123, options [nop,nop,TS val 8613320 ecr 11461347], length 0 E..4.#@[email protected]....:-.6.pR....{./..... ..m..... [root@slave ~]# tcpdump -i eth0 -s0 -nn -A tcp dst port 3306 and dst host 192.168.30.117 tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes 15:20:52.076327 IP 192.168.30.115.59899 > 192.168.30.117.3306: Flags [P.], seq 201259223:201259232, ack 2661648116, win 115, options [nop,nop,TS val 8623261 ecr 9819401], length 9 E..=..@[email protected].&..... ....... .....abc. 15:20:52.076821 IP 192.168.30.115.59899 > 192.168.30.117.3306: Flags [.], ack 12, win 115, options [nop,nop,TS val 8623261 ecr 9887103], length 0 E..4..@[email protected]#q..... ........ 15:20:52.077609 IP 192.168.30.115.59899 > 192.168.30.117.3306: Flags [P.], seq 9:32, ack 12, win 115, options [nop,nop,TS val 8623262 ecr 9887103], length 23 E..K..@[email protected]....... .............select * from test 15:20:52.118046 IP 192.168.30.115.59899 > 192.168.30.117.3306: Flags [.], ack 82, win 115, options [nop,nop,TS val 8623303 ecr 9887105], length 0 E..4..@[email protected]"...... 观察抓包情况,发现所有的更新操作都在master,查询操作都在slave 上面
登录主从数据库查看数据是否一致
# master mysql> use abc Database changed mysql> select * from test; +------+ | id | +------+ | 1 | +------+ 1 row in set (0.00 sec) # slave mysql> use abc Database changed mysql> select * from test; +------+ | id | +------+ | 1 | +------+ 1 row in set (0.00 sec) # 发现数据一致
四、Amoeba简单的优化配置:
1、 修改amoeba启动参数,增加JAVA虚拟机的内存,修改amoeba执行程序,查找DEFAULT_OPTS,修改为以下内容:
DEFAULT_OPTS="-server -Xms1024m -Xmx1024m -Xss256k"
2、 amoeba.xml中关于多线程和网络的优化
[root@amoeba ~]# vim /usr/local/amoeba/conf/amoeba.xml # 修改如下几项500 500 500 256 128
3、 amoeba.xml中还有一个处理客户端连接和网络信息使用CPU核数的配置,不过默认配置是主机拥有的CPU核的数量,一般不用修改,如果你的amoeba负载较高,并且机器上还有其他服务,你就可以降低这个配置,避免系统或者其他服务没有资源,或者出现资源争抢,从而导致整理的处理能力下降。
查找amoeba.xml文件中connectionManagerList关键字,修改
[root@amoeba ~]# vi /usr/local/amoeba/conf/amoeba.xml # 取消注释,并设置processors数量。
到此,MySQL 5.6基于GTID的复制,以及Amoeba读写分离的实现配置完成。