搭建MySQL的主从复制和读写分离
+--------+ (write) +--------+
| client | +---------------------+| master |
+--------+| | +--------+|
| | |
| | |
| +--------+ (read) |
(read) +--------+| amoeba |+---------------------|-----------+
(write) | +--------+| | |
| | | |
| (read)| | |
+--------+| | +--------+ | +--------+
| client | +-| slave1 |+---------+----------+| slave2 |
+--------+ +--------+ (replication) +--------+
master mysql:172.17.0.4
slave1 mysql:172.17.0.5
slave2 mysql:172.17.0.6
mysql-proxy(amoeba):172.17.0.8
Test host:172.17.0.7
主从复制：
master mysql
：
安装mysqlserver和mysql
yum install mysql-server mysql -y
修改配置文件
vim /etc/my.cnf.d/server.cnf
[mysqld]
server-id = 1
log-bin = master-bin
启动mysql
/etc/init.d/mysql start
修改root密码
mysqladmin -uroot -p password mysql
登陆mysql测试并查看master状态
mysql -uroot -pmysql
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 22449
Server version: 5.5.47-MariaDB-log MariaDB Server
Copyright (c) 2000, 2015, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MariaDB [(none)]> show master status;
+------------------+----------+--------------+------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql-bin.000001 | 3648 | | |
+------------------+----------+--------------+------------------+
1 row in set (0.03 sec)
创建主从同步账号
MariaDB [(none)]> grant replication slave on *.* to 'mysqlmaster'@'172.17.0.%' identified by '123456';
slave1 mysql
：
安装mysqlserver和mysql
yum install mysql-server mysql -y
修改配置文件
vim /etc/my.cnf.d/server.cnf
[mysqld]
server-id = 2 #id必须唯一
log-bin = slave-bin
启动mysql
/etc/init.d/mysql start
修改root密码
mysqladmin -uroot -p password mysql
创建同步文件
MariaDB [(none)]> change master to master_host='172.17.0.4',master_user='mysqlmaster',master_password='123456',master_log_file='mysql-bin.000001',master_log_pos=3648;
MariaDB [(none)]> start slave;
查看是否成功，确保下面两项为Yes
MariaDB [(none)]> show slave status\G;
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
master mysql
：
在master mysql上创建数据查看slave1 mysql是否同步
MariaDB [(none)]> create database new1;
Query OK, 1 row affected (0.00 sec)
MariaDB [(none)]> create database new2;
Query OK, 1 row affected (0.00 sec)
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| new1 |
| new2 |
| performance_schema |
| test |
+--------------------+
6 rows in set (0.00 sec)
slave1 mysql
:
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| new1 |
| new2 |
| performance_schema |
| test |
+--------------------+
6 rows in set (0.00 sec)
我们生产环境中会碰到这种情况：备份主机数据，或者添加一台主机。进行双主机的结构。
另外就是在线上中途添加更多的从机。
而我们知道，从机上设置 slave 时要指定 master_log_file 和 master_log_pos, 即指定binlog文件和偏移值。
这也就是说，从机是可以从任意位置的 binlog 文件中进行数据的同步。比如：我们将 binlog 文件备份到其它某处放置，某天，数据库出问题了，需要对某些数据进行数据恢复，这时候从该文件中进行恢复。
添加一个新的从机，可以有两种方式：从 master 机器复制; 另一种是直接从 slave 复制.
mysql-主从结构添加新的slave
两种解决办法
1.copy master
master mysql
：
锁定数据库
MariaDB [(none)]> flush tables with read lock;
Query OK, 0 rows affected (0.04 sec)
查看主机状态，几下file position参数
MariaDB [(none)]> show master status;
+------------------+----------+--------------+------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+------------------+----------+--------------+------------------+
| mysql-bin.000001 | 3974 | | |
+------------------+----------+--------------+------------------+
备份所有数据库
mysqldump --all-databases -uroot -pmysql > backup.sql
拷贝到准备新加的slave主机
scp backup.sql root@172.17.0.6:/root
slave2 mysql
:
安装mysqlserver和mysql
yum install mysql-server mysql -y
修改配置文件
vim /etc/my.cnf.d/server.cnf
[mysqld]
server-id = 3 #id必须唯一
log-bin = slave2-bin
启动mysql
/etc/init.d/mysql start
修改root密码
mysqladmin -uroot -p password mysql
导入主服务器scp过来的数据库
mysql -uroot -pmysql < backup.sql
创建同步文件
MariaDB [(none)]> change master to master_host='172.17.0.4',master_user='mysqlmaster',master_password='123456',master_log_file='mysql-bin.000001',master_log_pos=3974;
MariaDB [(none)]> start slave;
查看是否成功，确保下面两项为Yes
MariaDB [(none)]> show slave status\G;
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
master mysql
：
创建数据验证是否添加成功
MariaDB [(none)]> create database new3;
Query OK, 1 row affected (0.00 sec)
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| new1 |
| new2 |
| new3 |
| performance_schema |
| test |
+--------------------+
6 rows in set (0.00 sec)
slave2 mysql
:
MariaDB [(none)]> create database new3;
Query OK, 1 row affected (0.00 sec)
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| new1 |
| new2 |
| new3 |
| performance_schema |
| test |
+--------------------+
6 rows in set (0.00 sec)
2 copy slave
复制从库要步骤：
====================
可以看到，从主库复制会有段时间锁表，这段时间会影响主库的使用。如果我们能直接从从库进行复制，就不会对主库产生影响了。但是，从从库复制要保证的是复制过程中从库上的数据不会发生变化，所以要先停掉从库。
1.停止从库: mysql> stop slave;
2.看当前从库的状态。和前面的看主库状态一样。但现在是从从库复制，所以查看从库状态：mysql> show slave status;
记下 Relay_Master_Log_file 和 Exec_Master_Log_Pos, 用处和前面一样.
3.备份从库数据.用 mysqldump
4.在新的从库上还原数据
5.设置新从库的 slave 参数.change master to master_host = '192.168.3.119',master_port = 3306,master_user = 'repl_user',master_password='root',master_log_file='master-bin.000005',master_log_pos=194244;
可以看到，虽然新从库是从从库复制的数据，但实际上 binlog 的 master 还是指向的主库。
另外，这里将 master_log_file 和 master_log_pos 设置成第 2 步中的 Relay_Master_Log_file 和 Exec_Master_Log_Pos
start slave;
mysql的主从复制+读写分离
+--------+ (write) +--------+
| client | +---------------------+| master |
+--------+| | +--------+|
| | |
| | |
| +--------+ (read) |
(read) +--------+| amoeba |+---------------------|-----------+
(write) | +--------+| | |
| | | |
| (read)| | |
+--------+| | +--------+ | +--------+
| client | +-| slave1 |+---------+----------+| slave2 |
+--------+ +--------+ (replication) +--------+
读写分离
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。再看下上面的架构图。
因为amoeba是java编写的，所以需要先安装java框架
Amoeba
：
java安装
下载java
wget http://download.oracle.com/otn-pub/java/jdk/7u79-b15/jdk-7u79-linux-x64.tar.gz
创建java目录，并解压
mkdir -p /usr/jdk
tar -xzvf jdk-7u79-linux-x64.tar.gz -C /usr/jdk
配置环境变量，在/etc/profile文件最后添加如下配置
vim /etc/profile
export JAVA_HOME=/usr/jdk/
export CLASSPATH=${JAVA_HOME}/lib
export PATH=${JAVA_HOME}/bin:$PATH
使配置文件生效
source /etc/profile
测试
java -version
java version "1.7.0_79"
Java(TM) SE Runtime Environment (build 1.7.0_79-b15)
Java HotSpot(TM) 64-Bit Server VM (build 24.79-b02, mixed mode)
证明已经安装完成
amoeba安装配置
下载解压
wget http://ufpr.dl.sourceforge.net/project/amoeba/Amoeba%20for%20mysql/3.x/amoeba-mysql-3.0.5-RC-distribution.zip
unzip amoeba-mysql-3.0.5-RC-distribution.zip
mv amoeba-mysql-3.0.5-RC /usr/local/
配置
vim amoeba-mysql-3.0.5-RC/conf/amoeba.xml （前段连接文件）
8066 ///////amoeba监听端口/////////
128
64
root ///Amoeba代理用户名/////
mysql ///Amoeba代理用户密码/////
${amoeba.home}/conf/access_list.conf
.......................
.......................
${amoeba.home}/conf/rule.xml
${amoeba.home}/conf/ruleFunctionMap.xml
${amoeba.home}/conf/functionMap.xml
1500
master ///////默认地址池////////
master //////写地址池///////////
vipdb //////读地址池////////
true
vim amoeba-mysql-3.0.5-RC/conf/dbServers.xml （后端数据库参数文件）
${defaultManager}
64
128
3306 /////数据库连接端口///////
test ////默认数据库////
amoeba ///主从数据库默认连接用户////
mysql ////主从数据库默认连接用户密码////
............................
............................
+---+
|
|
172.17.0.4 |
|
|
|
|
|
|+-------//////定义后端数据库，dbServer可以随意命名，但自己必须清楚哪个是主，那个是从，而且主服务器命名要和amoeba.xml中writePool相对应，从服务器对应下面
172.17.0.5 |virturl dbServer中的poolNames ip对应各个db///////
|
|
|
|
|
172.17.0.6 |
+---|
+---+
|
|
1 |
|+-------///第一行的dbserver name命名一定和amoeba.xml的readPool相对应，property name配置从服务器的集合，可以是一个，可以是多个！
|
slave1,slave2 |
|
+---+
vim amoeba-mysql-3.0.5-RC/jvm.properties （java虚拟机配置）
把原来的这一句JVM_OPTIONS="-server -Xms256m -Xmx1024m -Xss196k -XX:PermSize=16m -XX:MaxPermSize=96m"
改成JVM_OPTIONS="-server -Xms1024m -Xmx1024m -Xss256k -XX:PermSize=16m -XX:MaxPermSize=96m"
在master，slave1，slave2分别授权dbServer.xml中定义的用户名和密码
MariaDB [(none)]> grant all on *.* to 'amoeba'@'%' identified by "mysql";
MariaDB [(none)]> grant all on *.* to 'amoeba'@'localhost' identified by "mysql";
启动amoeba
/usr/local/amoeba-mysql-3.0.5-RC/bin/launcher&
查看进程(如果启动成功，会看到如下进程)
ps -ef
root 467 337 0 12:51 pts/0 00:00:00 /bin/bash amoeba-mysql-3.0.5-RC/bin/launcher
root 472 467 0 12:51 pts/0 00:00:05 /usr/local/jdk1.7.0_67/bin/java -server -Xms1024m -Xmx1024m -Xss256k -XX:PermSize=16m
root 473 467 0 12:51 pts/0 00:00:00 tail -f /usr/local/amoeba-mysql-3.0.5-RC/logs/console.log
查看监听端口
netstat -anpl
tcp 0 0 :::8066 :::* LISTEN 472/java
tcp 0 0 ::ffff:172.17.0.8:8066 ::ffff:172.17.0.7:39978 ESTABLISHED 472/java
tcp 0 0 ::ffff:172.17.0.8:46624 ::ffff:172.17.0.5:3306 ESTABLISHED 472/java
tcp 0 0 ::ffff:172.17.0.8:41286 ::ffff:172.17.0.4:3306 ESTABLISHED 472/java
Test host测试
测试是拿amoeba.xml中定义的用户名密码去测试，千万别被这地方绕进去
[root@7898596a875b ~]# mysql -uroot -p -h272.17.0.8 -P8066
Enter password:
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MySQL connection id is 1265630343
Server version: 5.1.45-mysql-amoeba-proxy-3.0.4-BETA MariaDB Server
Copyright (c) 2000, 2016, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MySQL [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| new1 |
| new2 |
| performance_schema |
| test |
+--------------------+
6 rows in set (0.00 sec)
测试读写分离
master mysql
:
在master上建表
MariaDB [(none)]> use new1;
MariaDB [new1]> create table student( id int(4) not null AUTO_INCREMENT, name char(20) not null, age tinyint(2) NOT NULL default '0', dept varchar(16) default NULL, primary key(id), KEY index_name (name) );
slave1,slave2
:
slave1
停掉slave
MariaDB [(none)]> stop slave;
Query OK, 0 rows affected (0.02 sec)
MariaDB [new1]> insert into new1.student(id,name) values(2,'slave');
Query OK, 1 row affected (0.03 sec)
MariaDB [new1]> select * from new1.student;
+----+-------+-----+------+
| id | name | age | dept |
+----+-------+-----+------+
| 2 | slave | 0 | NULL |
+----+-------+-----+------+
1 row in set (0.00 sec)
slave2
MariaDB [(none)]> stop slave;
Query OK, 0 rows affected (0.02 sec)
MariaDB [(none)]> insert into new1.student(id,name) values(3,'slave');
Query OK, 1 row affected (0.04 sec)
MariaDB [(none)]> select * from new1.student;
+----+-------+-----+------+
| id | name | age | dept |
+----+-------+-----+------+
| 3 | slave | 0 | NULL |
+----+-------+-----+------+
1 row in set (0.00 sec)
master上也插入一条数据
MariaDB [new1]> insert into new1.student(id,name) values(1,'slave');
Query OK, 1 row affected (0.02 sec)
查询插入
MariaDB [new1]> select * from new1.student;
+----+-------+-----+------+
| id | name | age | dept |
+----+-------+-----+------+
| 1 | slave | 0 | NULL |
+----+-------+-----+------+
1 row in set (0.00 sec)
Test host测试
MySQL [new1]> select * from new1.student;
+----+-------+-----+------+
| id | name | age | dept |
+----+-------+-----+------+
| 3 | slave | 0 | NULL |
+----+-------+-----+------+
1 row in set (0.00 sec)
第一次查询发现只查询到slave的数据，以为另一个slave读写分离没有做成功，再次查询发现
amoeba是轮询着从从数据库池里读取数据
MySQL [new1]> select * from new1.student;
+----+-------+-----+------+
| id | name | age | dept |
+----+-------+-----+------+
| 2 | slave | 0 | NULL |
+----+-------+-----+------+
1 row in set (0.00 sec)
再插入一条数据，发现查询不到插入的，还是只能查询到slave上数据
MySQL [new1]> insert into student(id,name) values(4,'yufyang');
Query OK, 1 row affected (0.02 sec)
MySQL [new1]> select * from new1.student;
+----+-------+-----+------+
| id | name | age | dept |
+----+-------+-----+------+
| 3 | slave | 0 | NULL |
+----+-------+-----+------+
1 row in set (0.00 sec)
MySQL [new1]> select * from new1.student;
+----+-------+-----+------+
| id | name | age | dept |
+----+-------+-----+------+
| 2 | slave | 0 | NULL |
+----+-------+-----+------+
1 row in set (0.01 sec)
master mysql
：
MariaDB [new1]> select * from new1.student;
+----+---------+-----+------+
| id | name | age | dept |
+----+---------+-----+------+
| 1 | slave | 0 | NULL |
| 4 | yufyang | 0 | NULL |
+----+---------+-----+------+
2 rows in set (0.00 sec)
发现刚才在测试机上通过amoeba插入的数据已经出现在主数据库的表中
开启slave
再次查询slave上的数据
MariaDB [new1]> select * from new1.student;
+----+---------+-----+------+
| id | name | age | dept |
+----+---------+-----+------+
| 1 | slave | 0 | NULL |
| 2 | slave | 0 | NULL |
| 4 | yufyang | 0 | NULL |
+----+---------+-----+------+
发现已经同步master，amoeba测试机上的数据了
新闻名称：搭建mysql的主从复制和读写分离
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