在Mysql官方帮助文档中，详细记录中Mysql的启动方式，有mysqld_safe、mysql.server、mysql_multi这三种。关于mysql_multi的介绍：


Mysqld_multi可以管理多个帧听不同Unix套接字文件和TCP/IP端口的连接的mysqld 进程。它可以启动或停止服务器，或报告它们的当前状态。


即可以管理多个实例。

笔者在之前也介绍过使用mysqld_safe启用多实例的方法，启动和关闭都指定配置文件，实例间是对立的，互不影响。成功的部署了多个实例主从Replication，今天也介绍下mysql_multi多实例管理，配置简单，方便管理。

1、首先配置my.cnf文件，列出我的Mysql配置文件：


  1. [mysqld_multi]


  3. mysqld = /usr/local/mysql/bin/mysqld_safe #根据自己的mysql目录配置


  5. mysqladmin = /usr/local/mysql/bin/mysqladmin


  7. [mysqld1]


  9. port = 3306


  11. socket = /tmp/mysql3306.sock


  13. basedir=/usr/local/mysql


  15. datadir=/mysqldata/data3306


  17. log-slow-queries=slow_query.txt


  19. long_query_time=2


  21. skip-locking


  23. skip-name-resolve


  25. skip-innodb


  27. max_allowed_packet = 256M


  29. query_cache_size=256M


  31. max_connections=2000


  33. max_connect_errors=10000


  35. key_buffer_size=6000M


  37. read_buffer_size=32M


  39. read_rnd_buffer_size = 32M


  41. myisam_sort_buffer_size=512M


  43. tmp_table_size=1024M


  45. old-passwords


  47. interactive_timeout=60


  49. wait_timeout=60


  51. connect_timeout=60


  53. table_cache=8192


  55. thread_cache_size=512


  57. sort_buffer_size=128M


  59. back_log = 500


  61. thread_concurrency=48


  63. expire_logs_days=10


  65. log-bin=mysql-bin


  67. [mysqld2]


  69. port = 3307


  71. socket = /tmp/mysql3307.sock


  73. basedir=/usr/local/mysql


  75. datadir=/mysqldata/data3307


  77. log-slow-queries=slow_query.txt


  79. long_query_time=2


  81. skip-locking


  83. skip-name-resolve


  85. skip-innodb


  87. max_allowed_packet = 256M


  89. query_cache_size=256M


  91. max_connections=2000


  93. max_connect_errors=10000


  95. key_buffer_size=6000M


  97. read_buffer_size=32M


  99. read_rnd_buffer_size = 32M


  101. myisam_sort_buffer_size=512M


  103. tmp_table_size=1024M


  105. old-passwords


  107. interactive_timeout=60


  109. wait_timeout=60


  111. connect_timeout=60


  113. table_cache=8192


  115. thread_cache_size=512


  117. sort_buffer_size=128M


  119. back_log = 500


  121. thread_concurrency=48


  123. expire_logs_days=10


  125. log-bin=mysql-bin


  127. [mysqldump]


  129. quick


  131. max_allowed_packet = 512M


  133. [mysql]


  135. no-auto-rehash


  137. [isamchk]


  139. key_buffer = 512M


  141. sort_buffer_size = 32M


  143. read_buffer = 2M


  145. write_buffer = 2M


  147. [myisamchk]


  149. key_buffer = 512M


  151. sort_buffer_size = 32M


  153. read_buffer = 2M


  155. write_buffer = 2M


  157. [mysqlhotcopy]


  159. interactive-timeout


2、初始化数据库目录：


  1. shell>cd /usr/local/mysql/;./scripts/mysql_install_db --datadir=/mysqldata/data3307/ --user=mysql


  3. shell>cd /usr/local/mysql/;./scripts/mysql_install_db --datadir=/mysqldata/data3306/ --user=mysql


初始话成功，会提示OK，否则查看数据库目录是否有权限。

3、启动多实例：


  1. shell>/usr/local/mysql/bin/mysqld_multi start 1-2


  3. 或


  5. shell>/usr/local/mysql/bin/mysqld_multi start 1


  7. shell>/usr/local/mysql/bin/mysqld_multi start 2


注意这里的1、2对应my.cnf配置文件 mysqld1、mysqld2，以此来区分。



4、本机登录Mysql，如3307端口：


  1. shell>mysql -S /tmp/mysql3307.sock


  3. mysql> show variables like 'datadir';


  5. +---------------+----------------------+


  7. | Variable_name | Value |


  9. +---------------+----------------------+


  11. | datadir | /mysqldata/data3307/ |


  13. +---------------+----------------------+


  15. 1 row in set (0.00 sec)

4、关闭数据库实例


  1. shell>/usr/local/mysql/bin/mysqld_multi stop 1-2


  3. 或


  5. shell>/usr/local/mysql/bin/mysqld_multi stop 1


  7. shell>/usr/local/mysql/bin/mysqld_multi stop 2