一.maxscale简介
1.MaxScale是maridb开发的一个mysql数据中间件，其配置简单，能够实现读写分离，并且可以根据主从状态实现写库的自动切换。
2.官网：
https://mariadb.com/kb/en/mariadb-enterprise/mariadb-maxscale-20/
二.安装
1.安装可以通过rpm安装
2.可以直接下载文件放入指定目录，本次采用第二种方法
#wget https://downloads.mariadb.com/MaxScale/2.0.2/centos/5Server/x86_64/maxscale-2.0.2.centos.5.tar.gz
#tar zxvf maxscale-2.0.2.centos.5.tar.gz
#mkdir /usr/local/maxscale
#mv ./maxscale-2.0.2/* /usr/local/maxscale/
#cp /usr/local/maxscale/etc/maxscale.cnf.template /etc/maxscale.cnf
修改启动脚本,使其可以提供service服务
#cp /usr/local/maxscale/share/maxscale/maxscale /etc/init.d/maxscale
#vi /etc/init.d/maxscale
将脚本中的///bin替换为/usr/local/maxscale/bin/maxscale
这将可以使用 service maxscale start|stop|restart启动停止或重启maxscale
三.账户配置
1.在主从库上授权两个账户
a.监视账户
create user maxscale_monitor@'192.168.1.%' identified by "123456";
grant replication slave, replication client on *.* to maxscale_monitor@'192.168.1.%';
b.路由账户
create user maxscale_route@'192.168.1.%' identified by "";
GRANT SELECT ON mysql.user TO maxscale_route@'192.168.1.%';
GRANT SELECT ON mysql.db TO maxscale_route@'192.168.1.%';
GRANT SELECT ON mysql.tables_priv TO maxscale_route@'192.168.1.%';
GRANT SHOW DATABASES ON *.* TO maxscale_route@'192.168.1.%';
四.读写分离配置
0.vi /etc/maxscale.cnf
基本配置
[maxscale]
# 开启线程个数，默认为1.设置为auto会同cpu核数相同
threads=auto
# timestamp精度
ms_timestamp=1
# 将日志写入到syslog中
syslog=1
# 将日志写入到maxscale的日志文件中
maxlog=1
# 不将日志写入到共享缓存中，开启debug模式时可打开加快速度
log_to_shm=0
# 记录告警信息
log_warning=1
# 记录notice
log_notice=1
# 记录info
log_info=1
# 不打开debug模式
log_debug=0
# 日志递增
log_augmentation=1# 相关目录设置
basedir=/usr/local/maxscale/
logdir=/u01/maxscale/logs/trace/
datadir=/u01/maxscale/data/
cachedir=/u01/maxscale/cache/
piddir=/u01/maxscale/tmp/
1.读写分离配置
a.配置两个server
[server1]
type=server
address=192.168.1.126
port=3306
protocol=MySQLBackend
serv_weight=3 #读的比重[server2]
type=server
address=192.168.1.84
port=3306
protocol=MySQLBackend
serv_weight=2 #读的比重
b.配置monitor
[MySQL Monitor]
type=monitor
module=mysqlmon
servers=server1,server2
user=maxscale_monitor
passwd=123456
monitor_interval=10000
c.配置读写分离
[Read-Write Service]
type=service
router=readwritesplit
servers=server1,server2
user=maxscale_route
passwd=123456
max_slave_connections=100% #所有的slave提供select查询服务
#use_sql_variables_in=all#动态参数可以走全部的数据库 [all|master] 如果设置为master的话前台看到的中文是乱码，一般建议设置为all
#weightby=serversize#权重设置
#enable_root_user=1#允许root用户登录执行
master_accept_reads=true #master是否接受读请求
#auth_all_servers=true#
#log_auth_warnings=true#身份验证失败和警告的日志记录，记录那些试图连接到MaxScale和来自哪里
#filters=Hint#强制select走master的选项
d.配置端口
[Read-Write Listener]
type=listener
service=Read-Write Service
protocol=MySQLClient
port=4006[MaxAdmin Listener]
type=listener
service=MaxAdmin Service
protocol=maxscaled
port=6603
socket=default
五.启动
1./usr/local/maxscale/bin/maxscale start
2.查看状态(以下的user和password均为默认账号密码):
/usr/local/maxscale/bin/maxadmin –user=admin –password=mariadb
(/usr/local/maxscale/bin/maxadmin -S /tmp/maxadmin.sock #使用该项也可以登录)
MaxScale> list servers
Servers.
-------------------+-----------------+-------+-------------+--------------------
Server | Address | Port | Connections | Status
-------------------+-----------------+-------+-------------+--------------------
server1 | 192.168.1.126 | 3306 | 2 | Master, Running
server2 | 192.168.1.84 | 3306 | 2 | Slave, Running
-------------------+-----------------+-------+-------------+--------------------
更多帮助可以使用 help命令来获得
如果想要更改maxadmin的密码在配置文件中加上
[MaxAdmin Service]
type=service
router=cli
user=maxscale
passwd=123456
3.设置服务器维护状态
MaxScale> set server server2 maintenance
MaxScale> list servers
-------------------+-----------------+-------+-------------+--------------------
Server | Address | Port | Connections | Status
-------------------+-----------------+-------+-------------+--------------------
server1 | 192.168.1.126 | 3306 | 1 | Master, Running
server2 | 192.168.1.84 | 3306 | 0 | Maintenance, Slave, Running
4.清除维护状态
MaxScale> clear server server2 maintenance
MaxScale> list servers
-------------------+-----------------+-------+-------------+--------------------
Server | Address | Port | Connections | Status
-------------------+-----------------+-------+-------------+--------------------
server1 | 192.168.1.126 | 3306 | 3 | Master, Running
server2 | 192.168.1.84 | 3306 | 3 | Slave, Running
-------------------+-----------------+-------+-------------+--------------------
六.只读,按一定比例分摊读
1.配置只读服务
[Read-Only Service]
type=service
router=readconnroute
servers=server1,server2
user=maxscale_route
passwd=123456
weightby=serv_weight
server1和server2增加分摊比例
[server1]
type=server
address=192.168.118.126
port=3306
protocol=MySQLBackend
serv_weight=3[server2]
type=server
address=192.168.118.84
port=3306
protocol=MySQLBackend
serv_weight=2
2.配置端口
[Read-Only Listener]
type=listener
service=Read-Only Service
protocol=MySQLClient
port=4008
3.重新启动
七.filter
1.读写分离,如果slave没有问题,默认读全部走slave,但有时候我们需要能够读取走master,这时候就需要配置filter
在读写分离项中配置,多个filter之前用’|’号分开
filters=Hint[Hint]
type=filter
module=hintfilter
重启maxscale
应用在sql查询中:
select * from table where id=10; — maxscale route to master
将使读走master
2.有时候我们希望一个数据表能到达指定服务器,则可以这样配置
[tableFilter]
type=filter
module=namedserverfilter
match=table_name1|table_name2|table_name3
options=ignorecase,extended #忽略大小写,并启用扩展配置,这将使用正则表达式
server=server1
ps:以上options中按文档应该ignorecase,extended两者都应该生效,但实际测试是发现前面的生效,后面的就不生效
读写分离路由中配置
filters=tableFilter
这将使带有table_name1,table_name2,table_name3的查询或更新,全部到达server1
八.测试和总结
1.如果你有用过mycat和amoeba,你将会发现maxscale配置更加简单一些,与前两者相比,maxscale并没有使用连接池(不知道是不是我理解有误)
2.mycat和amoeba作为中间件,客户端在连接时候,账号和密码是在其配置文件中指定.但maxscale并不是,而是要求在后端(server1和server2)上定义账号,maxscale并不验证账号密码正确性,而是有后端去验证.
这项相比前两者,更加透明.
