MySQL router

MySQL Router is a building block for high availability (HA) solutions. It simplifies application development
by intelligently routing connections to MySQL servers for increased performance and reliability.

MySQL Router 8 fully supports MySQL 5.7 and MySQL 8, and it replaces the MySQL Router 2.x series. If
you currently use Router 2.0 or 2.1 then we recommend upgrading your installation to MySQL Router 8.

1 mysql router 安装

==mysqlroueter 2.1，本测试环境是mysql 5.6.15, Kylin Linux release 3.3.1707 (Core)
[root@mysqlhq soft]# rpm -ivh mysql-router-2.1.6-1.el6.x86_64.rpm
warning: mysql-router-2.1.6-1.el6.x86_64.rpm: Header V3 DSA/SHA1 Signature, key ID 5072e1f5: NOKEY
Preparing...                          ################################# [100%]
Updating / installing...
   1:mysql-router-2.1.6-1.el6         ################################# [100%]
[root@mysqlhq soft]# whereis mysqlrouter
mysqlrouter: /usr/bin/mysqlrouter /usr/lib64/mysqlrouter /etc/mysqlrouter
[root@mysqlhq soft]# ll /usr/bin/mysqlrouter
-rwxr-xr-x 1 root root 23592 Feb 21  2018 /usr/bin/mysqlrouter
[root@mysqlhq soft]# which mysqlrouter
/usr/bin/mysqlrouter
[root@mysqlhq soft]# rpm -qa|grep mysql-router
mysql-router-2.1.6-1.el6.x86_64
[root@mysqlhq soft]# ll /etc/mysqlrouter/
total 4
-rw-r--r-- 1 root root 1231 Feb 21  2018 mysqlrouter.conf
[root@mysqlhq soft]# ll /etc/init.d/mysqlrouter
-rwxr-xr-x 1 root root 2879 Feb 21  2018 /etc/init.d/mysqlrouter
[root@mysqlhq ~]# ll /usr/lib64/mysqlrouter
total 2592
-rwxr-xr-x 1 root root    9424 Feb 21  2018 keepalive.so
-rwxr-xr-x 1 root root   24136 Feb 21  2018 logger.so
-rwxr-xr-x 1 root root  124416 Feb 21  2018 metadata_cache.so
-rwxr-xr-x 1 root root   30096 Feb 21  2018 mysql_protocol.so
-rwxr-xr-x 1 root root  210504 Feb 21  2018 routing.so
-rwxr-xr-x 1 root root 2241288 Feb 21  2018 x_protocol.so

#m-s架构
#m 192.168.19.145
#s 192.168.19.227
[root@mysqlhq mysqlrouter]# vim mysqlrouter.conf
[DEFAULT]
logging_folder = /var/log/mysqlrouter/
plugin_folder = /usr/lib64/mysqlrouter
runtime_folder = /var/run/mysqlrouter
config_folder = /etc/mysqlrouter

[logger]
level = info

[routing:read_write]
bind_address = 192.168.19.145
bind_port = 7001
mode = read-write
destinations = 192.168.19.145:3306,192.168.19.227:3306
max_connections = 1024
max_connect_errors = 100
client_connect_timeout = 6
connect_timeout=3
# If no plugin is configured which starts a service, keepalive
# will make sure MySQL Router will not immediately exit. It is
# safe to remove once Router is configured.
[routing:read_only]
bind_address = 192.168.19.145
bind_port = 7002
mode = read-only
destinations = 192.168.19.145:3306,192.168.19.227:3306
max_connections = 1024
max_connect_errors = 100
client_connect_timeout = 6
connect_timeout=3

[keepalive]
interval = 60
[root@mysqlhq mysqlrouter]# mysqlrouter -v
MySQL Router v2.1.6 on Linux (64-bit) (GPL community edition)
[root@mysqlhq mysqlrouter]# groupadd  mysqlrouter
groupadd: group 'mysqlrouter' already exists
[root@mysqlhq mysqlrouter]# useradd -g mysqlrouter mysqlrouter
useradd: user 'mysqlrouter' already exists
[root@mysqlhq mysqlrouter]# id mysqlrouter
uid=989(mysqlrouter) gid=984(mysqlrouter) groups=984(mysqlrouter)
[root@mysqlhq mysqlrouter]#  chown -R mysqlrouter:mysqlrouter /etc/mysqlrouter
[root@mysqlhq mysqlrouter]# /usr/bin/mysqlrouter  -c  /etc/mysqlrouter/mysqlrouter.conf  &
[1] 3577
[root@mysqlhq mysqlrouter]# ps -ef|grep mysqlrouter
root      3577   831  0 16:57 pts/0    00:00:00 /usr/bin/mysqlrouter -c /etc/mysqlrouter/mysqlrouter.conf
root      3588   831  0 16:57 pts/0    00:00:00 grep --color=auto mysqlrouter
[root@mysqlhq mysqlrouter]# netstat -lnt|grep 7001
tcp        0      0 192.168.19.145:7001     0.0.0.0:*               LISTEN 

[root@mysqlhq ~]#  cd /var/log/mysqlrouter/
[root@mysqlhq mysqlrouter]# vim mysqlrouter.log
2019-01-14 16:57:10 WARNING [7f266a1d1700] [routing:read_only] setup_tcp_service() error from bind(): Cannot assign requested address
2019-01-14 16:57:10 ERROR   [7f266a1d1700] routing:read_only: Setting up TCP service using 192.168.20.118:7002: [routing:read_only] Failed to setup service socket: Cannot assign requested address
2019-01-14 16:57:10 INFO    [7f26699d0700] [routing:read_write] started: listening on 192.168.19.145:7001; read-write
2019-01-14 16:57:10 INFO    [7f266a9d2700] keepalive started with interval 60
2019-01-14 16:57:10 INFO    [7f266a9d2700] keepalive
2019-01-14 16:58:10 INFO    [7f266a9d2700] keepalive

2 启动，测试mysql router

[mysql@mysqlhq ~]$ mysql  -h 192.168.19.145  -u system -p*** -P 7001
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 312548
Server version: 5.6.15-log MySQL Community Server - (GPL)

Copyright (c) 2000, 2013, 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.

(system@192.168.19.145:7001) [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| test               |
| zabbix             |
+--------------------+
(system@192.168.19.145:7001) [(none)]> show variables like '%read_only%';
+------------------+-------+
| Variable_name    | Value |
+------------------+-------+
| innodb_read_only | OFF   |
| read_only        | OFF   |
| tx_read_only     | OFF   |
+------------------+-------+

[mysql@mysqlhq ~]$ mysql  -h 192.168.19.145  -u system -p*** -P 7001 -e "select @@hostname;"
Warning: Using a password on the command line interface can be insecure.
+------------+
| @@hostname |
+------------+
| mysqlhq    |
+------------+

[root@mysqlhq mysqlrouter]# netstat -lnt|grep 7002  #7002端口没有启动起来，log中没有报错信息
检查配置文件，发现ip写错了
[routing:read_only]
bind_address = 192.168.20.118 #此处修改为192.168.19.145
重新启动mysqlrouter
[root@mysqlhq mysqlrouter]# /usr/bin/mysqlrouter --help
[root@mysqlhq mysqlrouter]# ps -ef|grep mysqlrouter
root      3577   831  0 16:57 pts/0    00:00:00 /usr/bin/mysqlrouter -c /etc/mysqlrouter/mysqlrouter.conf
root      4266  4138  0 17:04 pts/2    00:00:00 tail -f mysqlrouter.log
root      5544   831  0 17:18 pts/0    00:00:00 grep --color=auto mysqlrouter
[root@mysqlhq mysqlrouter]# kill 3577
[root@mysqlhq mysqlrouter]#  /usr/bin/mysqlrouter -c /etc/mysqlrouter/mysqlrouter.conf &
[root@mysqlhq mysqlrouter]# netstat -lnt|grep 7001
tcp        0      0 192.168.19.145:7001     0.0.0.0:*               LISTEN
[root@mysqlhq mysqlrouter]# netstat -lnt|grep 7002
tcp        0      0 192.168.19.145:7002     0.0.0.0:*               LISTEN
日志信息
2019-01-14 17:18:13 INFO    [7faef06c7700] keepalive started with interval 60
2019-01-14 17:18:13 INFO    [7faef06c7700] keepalive
2019-01-14 17:18:13 INFO    [7faeefec6700] [routing:read_only] started: listening on 192.168.19.145:7002; read-only
2019-01-14 17:18:13 INFO    [7faeef6c5700] [routing:read_write] started: listening on 192.168.19.145:7001; read-write
在2个port上进行查询
[mysql@mysqlhq scripts]$ mysql  -h 192.168.19.145  -u system -p*** -P 7001 -e "select @@hostname;"
Warning: Using a password on the command line interface can be insecure.
+------------+
| @@hostname |
+------------+
| mysqlhq    |
+------------+
[mysql@mysqlhq scripts]$ mysql  -h 192.168.19.145  -u system -p*** -P 7002 -e "select @@hostname;"
Warning: Using a password on the command line interface can be insecure.
+------------+
| @@hostname |
+------------+
| mysqlhq    |
+------------+

(system@192.168.19.145:7001) [(none)]> select @@port;
+--------+
| @@port |
+--------+
| 3306 |
+--------+

3 性能--

Deploying MySQL Router
Performance Recommendations
For best performance, MySQL Router is typically installed on the same host as the application that uses it. Possible reasons include:
为了获得更好的性能，建议把mysql router安装在application的主机上
　　To allow local UNIX domain socket connections to the application, instead of TCP/IP. 允许本地UNIX域套接字连接到应用程序，替代TCP/IP
　　To decrease network latency. 减少网络的潜在因素
　　To allow MySQL Router to connect to MySQL without requiring extra accounts for the Router's host, for MySQL accounts that are created specifically
　　for application hosts, such as myapp@198.51.100.45 instead of a value like myapp@%. 账号安全
　　Typically application servers are easiest to scale. 通常，应用服务器是最容易伸缩的
　　You can run several instances of MySQL Router on your network, and do not need to isolate the router to a single machine or even a single
　　Router instance. This is because MySQL Router has no affinity for any particular server or host.

https://dev.mysql.com/doc/mysql-router/2.1/en/mysql-router-preface.html