# 起動していたら停止
% sudo /opt/local/share/mysql5/mysql/mysql.server stop
% sudo launchctl load -w /Library/LaunchDaemons/org.macports.mysql5.plist

# ここに入っている + pathは通しておく
% which mysql5
/opt/local/bin/mysql5

# エラーになるのでリンクを張っておく等
% sudo ln -s /opt/local/bin/my_print_defaults5 /opt/local/bin/my_print_defaults
% mkdir -p /Users/satoshi.tanaka/var/mysql1
% mkdir -p /Users/satoshi.tanaka/var/mysql2
% mkdir -p /Users/satoshi.tanaka/var/log

# ~/.my.cnf を準備, user名やportなどは適当に変更すること
% cat ~/.my.cnf
[mysqld_multi]
mysqld     = /opt/local/lib/mysql5/bin/mysqld_safe
mysqladmin = /opt/local/lib/mysql5/bin/mysqladmin
user       = root

[mysqld1]
server-id  = 1
socket     = /tmp/mysql1.sock
port       = 13306
pid-file   = /tmp/mysql1.pid
datadir    = /Users/satoshi.tanaka/var/mysql1
language   = /opt/local/share/mysql5/mysql/english
user       = satoshi.tanaka
log        = /Users/satoshi.tanaka/var/log/mysqld1.log
log-error  = /Users/satoshi.tanaka/var/log/mysqld1.error.log

[mysqld2]
server-id  = 2
socket     = /tmp/mysql2.sock
port       = 13307
pid-file   = /tmp/mysql2.pid
datadir    = /Users/satoshi.tanaka/var/mysql2
language   = /opt/local/share/mysql5/mysql/english
user       = satoshi.tanaka
log        = /Users/satoshi.tanaka/var/log/mysqld2.log
log-error  = /Users/satoshi.tanaka/var/log/mysqld2.error.log

# datadirの準備
% mysql_install_db5 --datadir=./var/mysql1/
% mysql_install_db5 --datadir=./var/mysql2/

# 起動して確認
% /opt/local/bin/mysqld_multi5 start --log=/tmp/mysqld_multi.log
% /opt/local/bin/mysqld_multi5 report --log=/tmp/mysqld_multi.log
Reporting MySQL servers
MySQL server from group: mysqld1 is running
MySQL server from group: mysqld2 is running
% mysql5 -S /tmp/mysql2.sock
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.1.63-log Source distribution

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