生产环境MySQL 5.5.x单机多实例配置实践

背景需求：
1)在一台新采购的服务器上通过源码编译安装一个版本为5.5.x以上的MySQL数据库，并将所有配置文件与数据等均存放在/opt/mysql，以便于今后实现快速迁移、复制和整体备份；
2)在同一个MySQL中运行两个实例，一个绑定在端口3306，一个绑定在端口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；
3)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，实现单机多实例的配置应用。

实施方案：
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。

配置过程：
1、源码编译安装MySQL
1)安装所需系统软件包
# yum -y install gcc gcc-c++ autoconf bison libjpeg libjpeg-devel libpng libpng-devel freetype freetype-devel libxml2 libxml2-devel zlib zlib-devel glibc glibc-devel glib2 glib2-devel bzip2 bzip2-devel ncurses ncurses-devel curl curl-devel e2fsprogs e2fsprogs-devel krb5 krb5-devel libidn libidn-devel openssl openssl-devel openldap openldap-devel nss_ldap openldap-clients openldap-servers

2)安装前的系统设置
# mkdir /opt/mysql //mysql安装目录
# mkdir /opt/mysql/data //mysql数据存放目录
# groupadd mysql //创建用户
# useradd -g mysql mysql //创建用户组
# chown mysql:mysql -R /opt/mysql/data //赋予数据存放目录权限

3)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，需要先在系统中源码编译安装cmake。
# mkdir /home/tools
# cd /home/tools
# wget http://www.cmake.org/files/v2.8/cmake-2.8.4.tar.gz
# tar xf cmake-2.8.4.tar.gz
# cd cmake-2.8.4
# ./configure
# make;make install

4)开始编译安装MySQL
# wget http://downloads.mysql.com/archives/mysql-5.5/mysql-5.5.19.tar.gz
# tar xf mysql-5.5.19.tar.gz
# cd mysql-5.5.19
# 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

2、创建单机支持多实例
1)进入MySQL主目录
# cd /opt/mysql/

2)删除默认的data目录
# rm -rf data

3)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

4)创建my.cnf配置文件
# vi etc/my.cnf

## This server may run 2+ separate instances ## So we use mysqld_multi to manage their services [mysqld_multi] mysqld = /opt/mysql/bin/mysqld_safe mysqladmin = /opt/mysql/bin/mysqladmin log = /opt/mysql/log/mysqld_multi.log user = root ## Used for stopping the server via mysqladmin #password = ## This is the general purpose database ## The locations are default # They are left in [mysqld] in case the server is started normally instead of by mysqld_multi [mysqld1] socket = /opt/mysql/run/mysqld.sock port = 3306 pid-file = /opt/mysql/run/mysqld.pid datadir = /opt/mysql/data lc-messages-dir = /opt/mysql/share/english ## These support master - master replication #auto-increment-increment = 4 #auto-increment-offset = 1 ## Since it is master 1 #log-bin = /opt/mysql/binlogs/bin-log-mysqld1 #log-bin-index = /opt/mysql/binlogs/bin-log-mysqld1.index #binlog-do-db = ## Leave this blank if you want to control it on slave #max_binlog_size = 1024M ## This is exlusively for mysqld2 ## It is on 3307 with data directory /opt/mysql/data2 [mysqld2] socket = /opt/mysql/run/mysqld.sock2 port = 3307 pid-file = /opt/mysql/run/mysqld.pid2 datadir = /opt/mysql/data2 lc-messages-dir = /opt/mysql/share/english ## Disable DNS lookups #skip-name-resolve ## These support master - slave replication log-bin = /opt/mysql/binlogs/bin-log-mysqld2 log-bin-index = /opt/mysql/binlogs/bin-log-mysqld2.index #binlog-do-db = ## Leave this blank if you want to control it on slave max_binlog_size = 1024M ## Relay log settings #relay-log = /opt/mysql/log/relay-log-mysqld2 #relay-log-index = /opt/mysql/log/relay-log-mysqld2.index #relay-log-space-limit = 4G ## Slow query log settings #log-slow-queries = /opt/mysql/log/slow-log-mysqld2 #long_query_time = 2 #log-queries-not-using-indexes ## The rest of the my.cnf is shared ## Here follows entries for some specific programs ## The MySQL server [mysqld] basedir = /opt/mysql tmpdir = /opt/mysql/tmp socket = /opt/mysql/run/mysqld.sock port = 3306 pid-file = /opt/mysql/run/mysqld.pid datadir = /opt/mysql/data lc-messages-dir = /opt/mysql/share/english skip-external-locking key_buffer_size = 16K max_allowed_packet = 1M table_open_cache = 4 sort_buffer_size = 64K read_buffer_size = 256K read_rnd_buffer_size = 256K net_buffer_length = 2K thread_stack = 128K ## Increase the max connections max_connections = 200 ## The expiration time for logs, including binlogs expire_logs_days = 14 ## Set the character as utf8 character-set-server = utf8 collation-server = utf8_unicode_ci ## This is usually only needed when setting up chained replication #log-slave-updates ## Enable this to make replication more resilient against server crashes and restarts ## but can cause higher I/O on the server #sync_binlog = 1 ## The server id, should be unique in same network server-id = 1 ## Set this to force MySQL to use a particular engine/table-type for new tables ## This setting can still be overridden by specifying the engine explicitly ## in the CREATE TABLE statement default-storage-engine = INNODB ## Uncomment the following if you are using InnoDB tables #innodb_data_home_dir = /opt/mysql/data #innodb_data_file_path = ibdata1:10M:autoextend #innodb_log_group_home_dir = /opt/mysql/data ## You can set .._buffer_pool_size up to 50 - 80 % of RAM ## but beware of setting memory usage too high innodb_buffer_pool_size = 16M innodb_additional_mem_pool_size = 2M ## Set .._log_file_size to 25 % of buffer pool size innodb_log_file_size = 5M innodb_log_buffer_size = 8M innodb_flush_log_at_trx_commit = 1 innodb_lock_wait_timeout = 50 [mysqldump] quick max_allowed_packet = 16M [mysql] no-auto-rehash [myisamchk] key_buffer_size = 8M sort_buffer_size = 8M [mysqlhotcopy] interactive-timeout [mysql.server] user = mysql [mysqld_safe] log-error = /opt/mysql/log/mysqld.log pid-file = /opt/mysql/run/mysqld.pid open-files-limit = 8192 [client] default-character-set = utf8

5)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

3、初始化数据库
1)切换到mysql用户，进入MySQL主目录
# su - mysql
# cd /opt/mysql/

2)初始化实例[mysqld1]和[mysqld2]
# scripts/mysql_install_db --basedir=/opt/mysql --user=mysql --datadir=/opt/mysql/data/
# scripts/mysql_install_db --basedir=/opt/mysql --user=mysql --datadir=/opt/mysql/data2/

3)回到root，创建mysqld_multi.server脚本
# exit
# mkdir -p /opt/mysql/init.d
# cp support-files/mysqld_multi.server /opt/mysql/init.d/
# vi /opt/mysql/init.d/mysqld_multi.server

#!/bin/sh # # A simple startup script for mysqld_multi by Tim Smith and Jani Tolonen. # This script assumes that my.cnf file exists either in /etc/my.cnf or # /root/.my.cnf and has groups [mysqld_multi] and [mysqldN]. See the # mysqld_multi documentation for detailed instructions. # # This script can be used as /etc/init.d/mysql.server # # Comments to support chkconfig on RedHat Linux # chkconfig: 2345 64 36 # description: A very fast and reliable SQL database engine. # # Version 1.0 # basedir=/opt/mysql bindir=/opt/mysql/bin conf=/opt/mysql/etc/my.cnf export PATH=$PATH:$bindir if test -x $bindir/mysqld_multi then mysqld_multi="$bindir/mysqld_multi"; else echo "Can't execute $bindir/mysqld_multi from dir $basedir"; exit; fi case "$1" in 'start' ) "$mysqld_multi" --defaults-extra-file=$conf start $2 ;; 'stop' ) "$mysqld_multi" --defaults-extra-file=$conf stop $2 ;; 'report' ) "$mysqld_multi" --defaults-extra-file=$conf report $2 ;; 'restart' ) "$mysqld_multi" --defaults-extra-file=$conf stop $2 "$mysqld_multi" --defaults-extra-file=$conf start $2 ;; *) echo "Usage: $0 {start|stop|report|restart}" >&2 ;; esac

4、整体备份MySQL
# cd /opt/
# tar czvf mysql_5.5.19_full.tar.gz mysql5519/

备份完成后，直接将mysql_5.5.19_full.tar.gz拿到其他服务器上，解压后便可以直接启用。

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

2)查看两个MySQL实例是否都已经成功启动
# netstat -lntp | grep mysqld

tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 28752/mysqld tcp 0 0 0.0.0.0:3307 0.0.0.0:* LISTEN 28756/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

6、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

7、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 '123456'
# /opt/mysql/bin/mysqladmin -u root -h127.0.0.1 -P3307 password '123456'

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

user = root ## Used for stopping the server via mysqladmin password = 123456

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 Database changed mysql> select Host,User,Password from user; //查看所有用户 +-----------+------+-------------------------------------------+ | Host | User | Password | +-----------+------+-------------------------------------------+ | localhost | root | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | | mysql-01 | root | | | 127.0.0.1 | root | | | ::1 | root | | | localhost | | | | mysql-01 | | | +-----------+------+-------------------------------------------+ 6 rows in set (0.00 sec) mysql> delete from user where password=""; //删除匿名连接的空密码帐号 Query OK, 5 rows affected (0.00 sec) mysql> flush privileges; //刷新权限 Query OK, 0 rows affected (0.00 sec) mysql> select Host,User,Password from user; //确认密码为空的用户是否已全部删除 +-----------+------+-------------------------------------------+ | Host | User | Password | +-----------+------+-------------------------------------------+ | localhost | root | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | +-----------+------+-------------------------------------------+ 1 row in set (0.00 sec) mysql> exit;

经验总结：
1、采用源码编译安装MySQL，可以方便我们自己组织所有MySQL相关文件的位置；同时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、本次方案仅仅实施了两个实例[mysqld1]与[mysqld2]，实际上我们可以通过这样的方式，拓展实现[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；
4、在单机运行多实例的情况下，不要使用mysql -hlocalhost或直接忽略-h参数登陆服务器，因为如果使用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实例中去，所以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。

BTW：如果大家认为我写的还可以，希望能给我的博客投个票，谢谢！O(∩_∩)O
http://blog.51cto.com/contest2012/7582