MySQL 5.5.x 单机多实例配置实践

背景/需求：
在一台服务器上通过源码编译安装一个版本为5.5以上的MySQL数据库；
将所有配置文件与数据等均存放在/opt/mysql，便于今后实现快速迁移、整体备份和快速复制；
在同一个MySQL中运行两个实例，一个绑定在端口3306，另一个绑定在端口3307；
绑定在3306端口的实例，不开启binlog，数据存放在/opt/mysql/data；
绑定在3307端口的实例，开启binlog，数据存放在/opt/mysql/data2；
两个实例均采用InnoDB作为默认的存储引擎，字符编码采用UTF-8；
两个实例均采用相同的性能优化配置参数；

实践/方案：
在编译安装时，将数据库的配置文件my.cnf以及data目录等均指向到/opt/mysql目录；
通过mysqld_multi的方式来管理两个不同的实例，采用相同的配置文件共享性能优化配置参数；
在同一个配置文件中，利用[mysqld1]与[mysqld2]标签实现不同实例的差异化配置；

配置步骤：
一、编译安装MySQL
1.安装cmake
MySQL从5.5版本开始，通过./configure进行编译配置方式已经被取消，取而代之的是cmake工具。
因此，我们首先要在系统中源码编译安装cmake工具。
# wget http://www.cmake.org/files/v2.8/cmake-2.8.4.tar.gz

# tar zxvf cmake-2.8.4.tar.gz

# cd cmake-2.8.4

# ./configure
# make
# make install

2.确保以下所需系统软件包已经被安装
通过 rpm -qa | grep name 的方式验证以下软件包是否已全部安装。

gcc* gcc-c++* autoconf* automake* zlib* libxml* ncurses-devel* libgcrypt* libtool*

如果缺少相关的软件包，可通过yum -y install 的方式在线安装，或直接从系统安装光盘中找到并通过rpm -ivh 的方式安装。

3. 安装前的系统设置
建立mysql安装目录及数据存放目录
# mkdir /opt/mysql
# mkdir /opt/mysql/data

创建用户和用户组
# groupadd mysql
# useradd -g mysql mysql

赋予数据存放目录权限
# chown mysql:mysql -R /opt/mysql/data

4.开始编译安装 MySQL
通过http://www.mysql.com/downloads/mysql官方网址或国内的sohu镜像下载软件包，如目前最新的MySQL 5.5.20。
# wget http://mirrors.sohu.com/mysql/MySQL-5.5/mysql-5.5.20.tar.gz

# tar zxvf mysql-5.5.20.tar.gz

# cd mysql-5.5.20
# cmake -DCMAKE_INSTALL_PREFIX=/opt/mysql \
-DSYSCONFDIR=/opt/mysql/etc \
-DMYSQL_DATADIR=/opt/mysql/data \
-DMYSQL_TCP_PORT=3306 \
-DMYSQL_UNIX_ADDR=/tmp/mysqld.sock \
-DMYSQL_USER=mysql \
-DEXTRA_CHARSETS=all \
-DWITH_READLINE=1 \
-DWITH_SSL=system \
-DWITH_EMBEDDED_SERVER=1 \
-DENABLED_LOCAL_INFILE=1 \
-DWITH_INNOBASE_STORAGE_ENGINE=1

# make
# make install

在make与make install的时候可以看到进度百分比，感觉这一点要比configure方式要好。

二、创建支持多实例的配置文件
进入MySQL主目录
# cd /opt/mysql/

删除默认的data目录
# rm -rf data

创建需要的目录
# mkdir etc tmp run log binlogs data data2
# chown -R mysql:mysql tmp run log binlogs data data2

创建my.cnf配置文件
# vim etc/my.cnf

001	## This server may run 2+ separate instances

002	## So we use mysqld_multi to manage their services

003	[mysqld_multi]

004	mysqld = /opt/mysql/bin/mysqld_safe

005	mysqladmin = /opt/mysql/bin/mysqladmin

006	log = /opt/mysql/log/mysqld_multi.log

007	user = root ## Used for stopping the server via mysqladmin

008	#password =

009

010	## This is the general purpose database

011	## The locations are default

012	# They are left in [mysqld] in case the server is started normally instead of by mysqld_multi

013

[mysqld1]

014	socket = /opt/mysql/run/mysqld.sock

015	port = 3306

016	pid-file = /opt/mysql/run/mysqld.pid

017	datadir = /opt/mysql/data

018	lc-messages-dir = /opt/mysql/share/english

019

020	## These support master - master replication

021	#auto-increment-increment = 4

022	#auto-increment-offset = 1  ## Since it is master 1

023	#log-bin = /opt/mysql/binlogs/bin-log-mysqld1

024	#log-bin-index = /opt/mysql/binlogs/bin-log-mysqld1.index

025	#binlog-do-db = ## Leave this blank if you want to control it on slave

026	#max_binlog_size = 1024M

027

028	## This is exlusively for mysqld2

029	## It is on 3307 with data directory /opt/mysqld/data2

030

[mysqld2]

031	socket = /opt/mysql/run/mysqld.sock2

032	port = 3307

033	pid-file = /opt/mysql/run/mysqld.pid2

034	datadir = /opt/mysql/data2

035	lc-messages-dir = /opt/mysql/share/english

036

037	## Disable DNS lookups

038	#skip-name-resolve

039

040	## These support master - slave replication

041	log-bin = /opt/mysql/binlogs/bin-log-mysqld2

042	log-bin-index = /opt/mysql/binlogs/bin-log-mysqld2.index

043	#binlog-do-db =  ## Leave this blank if you want to control it on slave

044	max_binlog_size = 1024M

045

046	## Relay log settings

047	#relay-log = /opt/mysql/log/relay-log-mysqld2

048	#relay-log-index = /opt/mysql/log/relay-log-mysqld2.index

049	#relay-log-space-limit = 4G

050

051	## Slow query log settings

052	#log-slow-queries = /opt/mysql/log/slow-log-mysqld2

053	#long_query_time = 2

054	#log-queries-not-using-indexes

055

056	## The rest of the my.cnf is shared

057	## Here follows entries for some specific programs

058	## The MySQL server

059

[mysqld]

060	basedir = /opt/mysql

061	tmpdir = /opt/mysql/tmp

062	socket = /opt/mysql/run/mysqld.sock

063	port = 3306

064	pid-file = /opt/mysql/run/mysqld.pid

065	datadir = /opt/mysql/data

066	lc-messages-dir = /opt/mysql/share/english

067

068	skip-external-locking

069	key_buffer_size = 16K

070	max_allowed_packet = 1M

071	table_open_cache = 4

072	sort_buffer_size = 64K

073	read_buffer_size = 256K

074	read_rnd_buffer_size = 256K

075	net_buffer_length = 2K

076	thread_stack = 128K

077

078	## Increase the max connections

079	max_connections = 200

080

081	## The expiration time for logs, including binlogs

082	expire_logs_days = 14

083

084	## Set the character as utf8

085	character-set-server = utf8

086	collation-server = utf8_unicode_ci

087

088	## This is usually only needed when setting up chained replication

089	#log-slave-updates

090

091	## Enable this to make replication more resilient against server crashes and restarts

092	## but can cause higher I/O on the server

093	#sync_binlog = 1

094

095	## The server id, should be unique in same network

096	server-id = 1

097

098	## Set this to force MySQL to use a particular engine/table-type for new tables

099	## This setting can still be overridden by specifying the engine explicitly

100	## in the CREATE TABLE statement

101	default-storage-engine = INNODB

102

103	## Uncomment the following if you are using InnoDB tables

104	#innodb_data_home_dir = /opt/mysql/data

105	#innodb_data_file_path = ibdata1:10M:autoextend

106	#innodb_log_group_home_dir = /opt/mysql/data

107	## You can set .._buffer_pool_size up to 50 - 80 % of RAM

108	## but beware of setting memory usage too high

109	innodb_buffer_pool_size = 16M

110	innodb_additional_mem_pool_size = 2M

111	## Set .._log_file_size to 25 % of buffer pool size

112	innodb_log_file_size = 5M

113	innodb_log_buffer_size = 8M

114	innodb_flush_log_at_trx_commit = 1

115	innodb_lock_wait_timeout = 50

116

117	[mysqldump]

118

quick

119	max_allowed_packet = 16M

120

121

[mysql]

122	no-auto-rehash

123

124	[myisamchk]

125	key_buffer_size = 8M

126	sort_buffer_size = 8M

127

128	[mysqlhotcopy]

129	interactive-timeout

130

131	[mysql.server]

132	user = mysql

133

134	[mysqld_safe]

135	log-error = /opt/mysql/log/mysqld.log

136	pid-file = /opt/mysql/run/mysqld.pid

137	open-files-limit = 8192

138

139

[client]

140	default-character-set = utf8

修改my.cnf读写权限，避免普通用户获取到MySQL密码
# chown -R root:root /opt/mysql/etc
# chmod 600 /opt/mysql/etc/my.cnf

三、初始化数据库
切换到mysql用户
# su - mysql

进入MySQL主目录
# cd /opt/mysql/

初始化实例[mysqld1]
# scripts/mysql_install_db --basedir=/opt/mysql --user=mysql --datadir=/opt/mysql/data/

初始化实例[mysqld2]
# scripts/mysql_install_db --basedir=/opt/mysql --user=mysql --datadir=/opt/mysql/data2/

返回到root
# exit

创建mysqld_multi.server脚本
# cp support-files/mysqld_multi.server /opt/mysql/init.d/

# vim /opt/mysql/init.d/mysqld_multi.server

01

#!/bin/sh

02

#

03	# A simple startup script for mysqld_multi by Tim Smith and Jani Tolonen.

04	# This script assumes that my.cnf file exists either in /etc/my.cnf or

05	# /root/.my.cnf and has groups [mysqld_multi] and [mysqldN]. See the

06	# mysqld_multi documentation for detailed instructions.

07

#

08	# This script can be used as /etc/init.d/mysql.server

09

#

10	# Comments to support chkconfig on RedHat Linux

11	# chkconfig: 2345 64 36

12	# description: A very fast and reliable SQL database engine.

13

#

14	# Version 1.0

15

#

16	basedir=/opt/mysql

17	bindir=/opt/mysql/bin

18

19	conf=/opt/mysql/etc/my.cnf

20	export PATH=$PATH:$bindir

21

22	if test -x $bindir/mysqld_multi

23

then

24	mysqld_multi="$bindir/mysqld_multi";

25

else

26	echo "Can't execute $bindir/mysqld_multi from dir $basedir";

27

exit;

28

fi

29

30	case "$1" in

31

'start' )

32	"$mysqld_multi" --defaults-extra-file=$conf start $2

33

;;

34

'stop' )

35	"$mysqld_multi" --defaults-extra-file=$conf stop $2

36

;;

37	'report' )

38	"$mysqld_multi" --defaults-extra-file=$conf report $2

39

;;

40	'restart' )

41	"$mysqld_multi" --defaults-extra-file=$conf stop $2

42	"$mysqld_multi" --defaults-extra-file=$conf start $2

43

;;

44

*)

45	echo "Usage: $0 {start|stop|report|restart}" >&2

46

;;

47

esac

四、整体备份MySQL
# cd /opt/
# tar czvf mysql_5.5.20_full.tar.gz mysql/

备份完成后，直接将mysql_5.5.20_full.tar.gz拿到其他服务器上，解压后便可以直接启用。

五、管理MySQL实例
同时 启动/关闭 实例 [mysqld1] 与 [mysqld2]：
# /opt/mysql/init.d/mysqld_multi.server start 1,2

然后，可以看到两个MySQL实例都已经成功的启动了。
# netstat -lntp | grep mysqld

1	tcp  0  0  0.0.0.0:3306  0.0.0.0:*  LISTEN 2850/mysqld

2	tcp  0  0  0.0.0.0:3307  0.0.0.0:*  LISTEN 2946/mysqld

同时 关闭 实例 [mysqld1] 与 [mysqld2]：
# /opt/mysql/init.d/mysqld_multi.server stop 1,2

仅 启动/关闭 实例[mysqld1]：
# /opt/mysql/init.d/mysqld_multi.server start 1
# /opt/mysql/init.d/mysqld_multi.server stop 1

六、登陆MySQL实例
在启动了实例[mysqld1]与[mysqld2]后，通过以下方式登陆不同的实例：

登陆[mysqld1]：
# /opt/mysql/bin/mysql -uroot -h127.0.0.1 -P3306 -p

登陆[mysqld2]：
# /opt/mysql/bin/mysql -uroot -h127.0.0.1 -P3307 -p

七、其他初始化设置
1. 为MySQL的root帐户设置初始密码
# /opt/mysql/bin/mysqladmin -u root -h127.0.0.1 -P3306 password 'new-password'
# /opt/mysql/bin/mysqladmin -u root -h127.0.0.1 -P3307 password 'new-password'

2. 修改my.cnf配置文件中MySQL的root账户密码
# vim /opt/mysql/etc/my.cnf

1	user = root ## Used for stopping the server via mysqladmin

2	password = new-password

3. 删除匿名连接的空密码帐号
分别登陆实例[mysqld1]与[mysqld2]，执行以下命令：
mysql>use mysql; //选择系统数据库mysql
mysql>select Host,User,Password from user; //查看所有用户
mysql>delete from user where password="";
mysql>flush privileges; //刷新权限
mysql>select Host,User,Password from user; //确认密码为空的用户是否已全部删除
mysql>exit;

八、经验总结
1.采用源码编译安装MySQL，可能在第一次会花费较多的时间，但却是非常值得的，因为我们可以自己组织所有MySQL相关文件的位置；并且经过源码编译安装后的MySQL，可以直接复制到其它服务器上运行，大大方便了我们今后的迁移、备份和新服务器的配置；

2.本文中仅仅用了两个实例[mysqld1]与[mysqld2]来举例，实际上我们可以通过这样的方式，实现[mysqld3],[mysqld4],[mysqld5]...等更多的实例；

3.MySQL自带了几个不同的配置文件，放置在/opt/mysql/support-files目录下，分别是my-huge.cnf,my- innodb-heavy-4G.cnf,my-large.cnf,my-medium.cnf,my-small.cnf，通过名称我们可以很直观的 了解到他们是针对不同的服务器配置的，本文中仅有的一点关于InnoDB的配置，是取自于my-small.cnf的，因为我是在虚拟机上进行的设置；在 生产环境中，我们可以通过参考my-huge.cnf或my-innodb-heavy-4G.cnf中的部分参数配置，来对服务器进行优化；

4.关于MySQL缓存参数的优化，主要用于提升I/O能力，可以参考这里：http://heylinux.com/archives/1389.html

5.在单机运行多实例的情况下，切忌使用 mysql -hlocalhost 或 直接忽略-h参数 登陆服务器，这应该算是MySQL的一个bug，就是如果使用localhost或忽略-h参数，而不是指定127.0.0.1的话，即使选择的端口是 3307，还是会登陆到3306中去，因此应尽量避免这种混乱的产生，统一用127.0.0.1绑定端口 或 采用socket 来登陆；

转：http://heylinux.com/archives/1689.html