mysql 5.5.22 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： 环境：redhat 5.4 64位 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 5.5.22。
# wget http://mirrors.sohu.com/mysql/mysql-5.5/mysql-5.5.22.tar.gz
# tar zxvf mysql-5.5.22.tar.gz
# cd mysql-5.5.22
# 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 init.d run log binlogs data data2
# chown -r mysql:mysql tmp run init.d log binlogs data data2
创建my.cnf配置文件
# vim 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/mysqld/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
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
#!/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
四、整体备份mysql # cd /opt/
# tar czvf mysql_5.5.22_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
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
user = root ## used for stopping the server via mysqladmin
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.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；
本文出自 “xmshuiyong’blog” 博客，请务必保留此出处http://xmshuiyong.blog.51cto.com/1980172/1113498