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 instances002## So we use mysqld_multi to manage their services003[mysqld_multi]004mysqld = /opt/mysql/bin/mysqld_safe005mysqladmin = /opt/mysql/bin/mysqladmin006log = /opt/mysql/log/mysqld_multi.log007user = root ## Used for stopping the server via mysqladmin008#password = 009?010## This is the general purpose database011## The locations are default012# They are left in [mysqld] in case the server is started normally instead of by mysqld_multi013[mysqld1]014socket = /opt/mysql/run/mysqld.sock015port = 3306016pid-file = /opt/mysql/run/mysqld.pid017datadir = /opt/mysql/data018lc-messages-dir = /opt/mysql/share/english019?020## These support master - master replication021#auto-increment-increment = 4022#auto-increment-offset = 1? ## Since it is master 1023#log-bin = /opt/mysql/binlogs/bin-log-mysqld1024#log-bin-index = /opt/mysql/binlogs/bin-log-mysqld1.index025#binlog-do-db = ## Leave this blank if you want to control it on slave026#max_binlog_size = 1024M027?028## This is exlusively for mysqld2029## It is on 3307 with data directory /opt/mysqld/data2030[mysqld2]031socket = /opt/mysql/run/mysqld.sock2032port = 3307033pid-file = /opt/mysql/run/mysqld.pid2034datadir = /opt/mysql/data2035lc-messages-dir = /opt/mysql/share/english036?037## Disable DNS lookups038#skip-name-resolve039?040## These support master - slave replication041log-bin = /opt/mysql/binlogs/bin-log-mysqld2042log-bin-index = /opt/mysql/binlogs/bin-log-mysqld2.index043#binlog-do-db =? ## Leave this blank if you want to control it on slave044max_binlog_size = 1024M045?046## Relay log settings047#relay-log = /opt/mysql/log/relay-log-mysqld2048#relay-log-index = /opt/mysql/log/relay-log-mysqld2.index049#relay-log-space-limit = 4G050?051## Slow query log settings052#log-slow-queries = /opt/mysql/log/slow-log-mysqld2053#long_query_time = 2054#log-queries-not-using-indexes055?056## The rest of the my.cnf is shared057## Here follows entries for some specific programs058## The MySQL server059[mysqld]060basedir = /opt/mysql061tmpdir = /opt/mysql/tmp062socket = /opt/mysql/run/mysqld.sock063port = 3306064pid-file = /opt/mysql/run/mysqld.pid065datadir = /opt/mysql/data066lc-messages-dir = /opt/mysql/share/english067?068skip-external-locking069key_buffer_size = 16K070max_allowed_packet = 1M071table_open_cache = 4072sort_buffer_size = 64K073read_buffer_size = 256K074read_rnd_buffer_size = 256K075net_buffer_length = 2K076thread_stack = 128K077?078## Increase the max connections079max_connections = 200080?081## The expiration time for logs, including binlogs082expire_logs_days = 14083?084## Set the character as utf8085character-set-server = utf8086collation-server = utf8_unicode_ci087?088## This is usually only needed when setting up chained replication089#log-slave-updates090?091## Enable this to make replication more resilient against server crashes and restarts092## but can cause higher I/O on the server093#sync_binlog = 1094?095## The server id, should be unique in same network096server-id = 1097?098## Set this to force MySQL to use a particular engine/table-type for new tables099## This setting can still be overridden by specifying the engine explicitly100## in the CREATE TABLE statement101default-storage-engine = INNODB102?103## Uncomment the following if you are using InnoDB tables104#innodb_data_home_dir = /opt/mysql/data105#innodb_data_file_path = ibdata1:10M:autoextend106#innodb_log_group_home_dir = /opt/mysql/data107## You can set .._buffer_pool_size up to 50 - 80 % of RAM108## but beware of setting memory usage too high109innodb_buffer_pool_size = 16M110innodb_additional_mem_pool_size = 2M111## Set .._log_file_size to 25 % of buffer pool size112innodb_log_file_size = 5M113innodb_log_buffer_size = 8M114innodb_flush_log_at_trx_commit = 1115innodb_lock_wait_timeout = 50116?117[mysqldump]118quick119max_allowed_packet = 16M120?121[mysql]122no-auto-rehash123?124[myisamchk]125key_buffer_size = 8M126sort_buffer_size = 8M127?128[mysqlhotcopy]129interactive-timeout130?131[mysql.server]132user = mysql133?134[mysqld_safe]135log-error = /opt/mysql/log/mysqld.log136pid-file = /opt/mysql/run/mysqld.pid137open-files-limit = 8192138?139[client]140default-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/sh02#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 or05# /root/.my.cnf and has groups [mysqld_multi] and [mysqldN]. See the06# mysqld_multi documentation for detailed instructions.07#08# This script can be used as /etc/init.d/mysql.server09#10# Comments to support chkconfig on RedHat Linux11# chkconfig: 2345 64 3612# description: A very fast and reliable SQL database engine.13#14# Version 1.015#16basedir=/opt/mysql17bindir=/opt/mysql/bin18?19conf=/opt/mysql/etc/my.cnf20export PATH=$PATH:$bindir21?22if test -x $bindir/mysqld_multi23then24??mysqld_multi="$bindir/mysqld_multi";25else26??echo "Can't execute $bindir/mysqld_multi from dir $basedir";27??exit;28fi29?30case "$1" in31????'start' )32????????"$mysqld_multi" --defaults-extra-file=$conf start $233????????;;34????'stop' )35????????"$mysqld_multi" --defaults-extra-file=$conf stop $236????????;;37????'report' )38????????"$mysqld_multi" --defaults-extra-file=$conf report $239????????;;40????'restart' )41????????"$mysqld_multi" --defaults-extra-file=$conf stop $242????????"$mysqld_multi" --defaults-extra-file=$conf start $243????????;;44????*)45????????echo "Usage: $0 {start|stop|report|restart}" >&246????????;;47esac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
1tcp? 0? 0? 0.0.0.0:3306? 0.0.0.0:*? LISTEN 2850/mysqld2tcp? 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
1user = root ## Used for stopping the server via mysqladmin2password = new-password3. 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