数据库学习之十四：读写分离 Atlas架构

十四、读写分离 Atlas架构

1、安装软件

rpm -ivh Atlas-2.2.1.el6.x86_64.rpm 

2、修改配置

cd /usr/local/mysql-proxy/

vim /usr/local/mysql-proxy/conf/test.cnf
[mysql-proxy]
admin-username = user
admin-password = pwd
proxy-backend-addresses = 10.0.0.55:3306
proxy-read-only-backend-addresses = 10.0.0.51:3306,10.0.0.52:3306
pwds = repl:3yb5jEku5h4=,mha:O2jBXONX098=
daemon = true
keepalive = true
event-threads = 8
log-level = message
log-path = /usr/local/mysql-proxy/log
sql-log=ON
proxy-address = 0.0.0.0:33060
admin-address = 0.0.0.0:2345
charset=utf8

/usr/local/mysql-proxy/bin/encrypt  123      ---->制作加密密码

启动atlas

/usr/local/Mysql-proxy/bin/mysql-proxyd test start
ps -ef |grep proxy

测试

测试读写分离：

读的测试
mysql -uroot -p123 -h10.0.0.53 -P33060 
show variables like "server_id";

写操作测试：

设置两个从节点只读
set global read_only=1;

连接测试

mysql -umha -pmha -h10.0.0.53 -P33060
create database db1;

管理atlas

连接管理接口：
mysql -uuser -ppwd -h127.0.0.1 -P2345
打印帮助：
mysql> select * from help;查看帮助命令
select * from backends;查看读写节点
动态添加删除节点：
REMOVE BACKEND 3;
ADD SLAVE 10.0.0.53:3306;
SAVE CONFIG;（配置文件中自动去除已经被删除的或者添加该节点）

扩展——atlas 自动分表

school.stu    1000w
id   name 

stu_0   stu_1   stu_2   stu_3    stu_4

以上分表方式,存数据非常均匀,取数据不均与,因为要考虑业务需求
如果业务查询热点数据集中在id是1-200w这些数据,那么读取就不均匀
取模分表

n/5  取余数  (0,1,2,3,4) 
(1)如果是  0  则分到 stu_0
(2)如果是  1  则分到 stu_1
(3)如果是  2  则分到 stu_2
(4)如果是  3  则分到 stu_3
(5)如果是  4  则分到 stu_4

取余数
配置文件
vim /usr/local/mysql-proxy/conf/test.cnf
tables = school.stu.id.5

重启atlas
(主库)手工创建,分表后的库和表,分别为定义的school  和 stu_0 stu_1 stu_2 stu_3 stu_4
create database school;
use school
create table stu_0 (id int,name varchar(20));
create table stu_1 (id int,name varchar(20));
create table stu_2 (id int,name varchar(20));
create table stu_3 (id int,name varchar(20));
create table stu_4 (id int,name varchar(20));

测试:

insert into stu values (3,"wang5");

insert into stu values (2,"li4");

insert into stu values (1,"zhang3");

insert into stu values (4,"m6");

insert into stu values (5,"zou7");

commit;

select * from stu_01 

或者 select * from stu where id=01