mysql 5.7 配置多实例 — mysqld_multi 方式

单机多实例可以有效的最大化服务器的利用率，mysql 多实例的实现方式也有两种：

    独立配置文件：每个实例有自己单独的配置文件 

    mysqld_multi 单一配置文件统一管理：实例在单一配置文件中统一配置管理

这里我们使用 mysqld_multi 方式来创建多实例，管理起来比较方便

假设我们在 /usr/local/mysql 目录安装了 mysql

接下来我们创建 3307 和 3308 两个新实例

创建实例数据目录

1. [root@localhost ~]# mkdir /usr/local/mysql{3307,3308}/data -p

2. [root@localhost ~]# chown mysql.mysql /usr/local/mysql{3307,3308} -R

    注意目录权限

初始化实例的数据库

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mysql_install_db 方式已经 deprecated 了，我们使用 mysqld 的 initialize 方法来做初始化

1. # --no-defaults 不读取默认的 /etc/my.cnf 全局配置文件 否则可能存在一些冲突问题

2. # --initialize-insecure 初始化且不需要生成密码，我不太喜欢那一大串字符...

3. # --basedir mysql 的安装目录

4. # --datadir 本实例的数据目录

5. # --user 这样生成的文件用户为 mysql

6. # --explicit_defaults_for_timestamp timestamp 已经 deprecated 了

7.  

8. #生成 3307 的数据目录

9. [root@localhost ~]# mysqld --no-defaults \

10. --initialize-insecure \

11. --basedir=/usr/local/mysql \

12. --datadir=/usr/local/mysql3307/data \

13. --user=mysql \

14. --explicit_defaults_for_timestamp

15.  

16. #生成 3308 的数据目录

17. [root@localhost ~]# mysqld --no-defaults \

18. --initialize-insecure \

19. --basedir=/usr/local/mysql \

20. --datadir=/usr/local/mysql3308/data \

21. --user=mysql \

22. --explicit_defaults_for_timestamp

多实例配置文件

这里上传我的配置，你也可以使用

mysqld_multi --example > /etc/my_multi.cnf

来生成多实例配置示例。

我不想在管理多实例时再使用 --defaults-file 选项来指定单独的实例配置文件，所以就写到默认的 my.cnf 文件中了，你可以自行选择是否使用单独的配置文件

1. [client]

2. port = 3306

3. socket = /tmp/mysql.sock

4.  

5. [mysqld]

6. port = 3306

7. socket = /tmp/mysql.sock

8. datadir = /usr/local/mysql/data

9. skip-external-locking

10. key_buffer_size = 32M

11. max_allowed_packet = 1M

12. table_open_cache = 128

13. sort_buffer_size = 768K

14. net_buffer_length = 8K

15. read_buffer_size = 768K

16. read_rnd_buffer_size = 512K

17. myisam_sort_buffer_size = 8M

18. thread_cache_size = 16

19. query_cache_size = 16M

20. tmp_table_size = 32M

21.  

22. log-error = /usr/local/mysql/mysql_error.log

23. pid-file = /usr/local/mysql/mysql.pid

24.  

25. explicit_defaults_for_timestamp = true

26. #skip-networking

27. max_connections = 100

28. max_connect_errors = 5

29. open_files_limit = 65535

30.  

31. log-bin=mysql-bin

32. binlog_format=mixed

33. server-id = 1

34. expire_logs_days = 10

35. early-plugin-load = ""

36.  

37. default_storage_engine = InnoDB

38. innodb_data_home_dir = /usr/local/mysql/data

39. innodb_data_file_path = ibdata1:10M:autoextend

40. innodb_log_group_home_dir = /usr/local/mysql/data

41. innodb_buffer_pool_size = 128M

42. innodb_log_file_size = 32M

43. innodb_log_buffer_size = 8M

44. innodb_flush_log_at_trx_commit = 1

45. innodb_lock_wait_timeout = 50

46.  

47. [mysqldump]

48. quick

49. max_allowed_packet = 16M

50.  

51. [mysql]

52. no-auto-rehash

53.  

54. [myisamchk]

55. key_buffer_size = 32M

56. sort_buffer_size = 768K

57. read_buffer = 2M

58. write_buffer = 2M

59.  

60. [mysqlhotcopy]

61. interactive-timeout

62.  

63. # 多实例配置 可以把下面的内容拿出来单独放一个配置文件 启动时 --defaults-file 即可

64. [mysqld_multi]

65. mysqld = /usr/local/mysql/bin/mysqld_safe

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

67. user = root

68. pass = 123456 #这里要注意5.7后用 pass 最方便, 5.6 用默认的 password 就好

69.  

70. # 实例3307

71. [mysqld3307]

72. port = 3307

73. socket = /tmp/mysql3307.sock

74. datadir = /usr/local/mysql3307/data

75. skip-external-locking

76. key_buffer_size = 32M

77. max_allowed_packet = 1M

78. table_open_cache = 128

79. sort_buffer_size = 768K

80. net_buffer_length = 8K

81. read_buffer_size = 768K

82. read_rnd_buffer_size = 512K

83. myisam_sort_buffer_size = 8M

84. thread_cache_size = 16

85. query_cache_size = 16M

86. tmp_table_size = 32M

87.  

88. log-error = /usr/local/mysql3307/mysql3307_error.log

89. pid-file = /usr/local/mysql3307/mysql3307.pid

90.  

91. explicit_defaults_for_timestamp = true

92. #skip-networking

93. max_connections = 100

94. max_connect_errors = 5

95. open_files_limit = 65535

96.  

97. log-bin=mysql-bin

98. binlog_format=mixed

99. server-id = 1

100. expire_logs_days = 10

101. early-plugin-load = ""

102.  

103. default_storage_engine = InnoDB

104. innodb_data_home_dir = /usr/local/mysql3307/data

105. innodb_data_file_path = ibdata1:10M:autoextend

106. innodb_log_group_home_dir = /usr/local/mysql3307/data

107. innodb_buffer_pool_size = 128M

108. innodb_log_file_size = 32M

109. innodb_log_buffer_size = 8M

110. innodb_flush_log_at_trx_commit = 1

111. innodb_lock_wait_timeout = 50

112.  

113. # 实例3308

114. [mysqld3308]

115. port = 3308

116. socket = /tmp/mysql3308.sock

117. datadir = /usr/local/mysql3308/data

118. skip-external-locking

119. key_buffer_size = 32M

120. max_allowed_packet = 1M

121. table_open_cache = 128

122. sort_buffer_size = 768K

123. net_buffer_length = 8K

124. read_buffer_size = 768K

125. read_rnd_buffer_size = 512K

126. myisam_sort_buffer_size = 8M

127. thread_cache_size = 16

128. query_cache_size = 16M

129. tmp_table_size = 32M

130.  

131. log-error = /usr/local/mysql3308/mysql3308_error.log

132. pid-file = /usr/local/mysql3308/mysql3308.pid

133.  

134. explicit_defaults_for_timestamp = true

135. #skip-networking

136. max_connections = 100

137. max_connect_errors = 5

138. open_files_limit = 65535

139.  

140. log-bin=mysql-bin

141. binlog_format=mixed

142. server-id = 1

143. expire_logs_days = 10

144. early-plugin-load = ""

145.  

146. default_storage_engine = InnoDB

147. innodb_data_home_dir = /usr/local/mysql3308/data

148. innodb_data_file_path = ibdata1:10M:autoextend

149. innodb_log_group_home_dir = /usr/local/mysql3308/data

150. innodb_buffer_pool_size = 128M

151. innodb_log_file_size = 32M

152. innodb_log_buffer_size = 8M

153. innodb_flush_log_at_trx_commit = 1

154. innodb_lock_wait_timeout = 50

这里其实有个小注意点：

在 [mysqld_multi ] 组里我并没有使用默认的 password 配置项， 而是用的 pass。

从5.6以后这货就被加密了必须用 -s 才能明文，mysqld_multi 读取的都是密文，无法 stop 实例。

运行多实例

1. # 可以看到多实例已经在运行了

2. # 多实例并不会影响默认实例的运行 我们仍可使用service mysql start|stop|restart|reload 管理默认实例

3. [root@localhost ~]# mysqld_multi start

4. [root@localhost ~]# mysqld_multi report

5. Reporting MySQL servers

6. MySQL server from group: mysqld3307 is running

7. MySQL server from group: mysqld3308 is running

设置实例密码

我们初始化实例的时候并没有设置root密码 默认为空 这是 --initialize-insecure 选项的作用

所以使用 mysqladmin 重置密码的时输入的原密码为空

1. [root@localhost local]# mysqladmin -u root -p password 123456 -S /tmp/mysql3307.sock

2. Enter password:

3. mysqladmin: [Warning] Using a password on the command line interface can be insecure.

4. Warning: Since password will be sent to server in plain text, use ssl connection to ensure password safety.

5.  

6. [root@localhost local]# mysqladmin -u root -p password 123456 -S /tmp/mysql3308.sock

7. Enter password:

8. mysqladmin: [Warning] Using a password on the command line interface can be insecure.

9. Warning: Since password will be sent to server in plain text, use ssl connection to ensure password safety.

我们可以为实例设置统一的密码，方便使用 mysqld_multi start|stop|reload 命令管理实例，否则你就得用 mysqladmin 这样玩了，自行选择

[root@localhost ~]# mysqladmin -uroot -pyourpassword -S /tmp/mysqlxxx.sock shutdown

配置完成

1. [root@localhost ~]# mysqld_multi start

2. [root@localhost ~]# mysqld_multi report

3. Reporting MySQL servers

4. MySQL server from group: mysqld3307 is running

5. MySQL server from group: mysqld3308 is running

6.  

7. [root@localhost ~]# mysqld_multi stop

8. [root@localhost ~]# mysqld_multi report

9. Reporting MySQL servers

10. MySQL server from group: mysqld3307 is not running

11. MySQL server from group: mysqld3308 is not running

12.  

13. [root@localhost ~]# mysqld_multi start 3308

14. [root@localhost ~]# mysqld_multi report

15. Reporting MySQL servers

16. MySQL server from group: mysqld3307 is not running

17. MySQL server from group: mysqld3308 is running

18.  

19. [root@localhost ~]# mysqld_multi stop 3308

20. [root@localhost ~]# mysqld_multi report

21. Reporting MySQL servers

22. MySQL server from group: mysqld3307 is not running

23.