一台服务器上的mysql多实例
使用不同的配置文件，启动文件，数据文件，日志文件。
一般用法是在/data目录下按照端口来配置多实例：/data/{3306,3307}/data
vim /data/3306/my.cnf
<code>
[client]
port = 3306
socket = /data/3306/mysql.sock
[mysql]
no-auto-rehash
[mysqld]
user = mysql
port = 3306
socket = /data/3306/mysql.sock
basedir = /application/mysql
datadir = /data/3306/data
open_files_limit = 1024
back_log = 600
max_connections = 800
max_connect_errors = 3000
table_cache = 614
external-locking = FALSE
max_allowed_packet = 8M
sort_buffer_size = 1M
join_buffer_size = 1M
thread_cache_size = 100
thread_concurrency = 2
query_cache_size = 2M
query_cache_limit = 1M
query_cache_min_res_unit = 2K
default_table_type = InnoDB
thread_stack = 192K
transaction_isolation = READ-COMMITTED
tmp_table_size = 2M
max_heap_table_size = 2M
long_query_time = 1
log_long_format
log-error = /data/3306/error.log
log-slow-queries = /data/3306/slow.log
pid-file = /data/3306/mysql.pid
log-bin = /data/3306/mysql-bin
relay-log = /data/3306/relay-bin
relay-log-info-file = /data/3306/relay-log.info
binlog_cache_size = 1M
max_binlog_cache_size = 1M
max_binlog_size = 2M
expire_logs_days = 7
key_buffer_size = 16M
read_buffer_size = 1M
read_md_buffer_size = 1M
bulk_insert_buffer_size = 1M
myisam_sort_buffer_size = 1M
myisam_max_sort_file_size = 10G
myisam_max_extra_sort_file_size = 10G
myisam_repair_threads = 1
myisam_recover
lower_case_table_names = 1
skip-name-resolve
slave-skip-errors = 1032,1062
replicate-ignore-db=mysql
server-id = 1
innodb_additional_mem_pool_size = 4M
innodb_buffer_pool_size = 32M
innodb_data_file_path = ibdata1:128M:autoextend
innodb_file_io_threads = 4
innodb_thread_concurrency = 8
innodb_flush_log_at_trx_commit = 2
innodb_log_buffer_size = 2M
innodb_log_file_size = 4M
innodb_log_files_in_group = 3
innodb_max_dirty_pages_pct = 90
innodb_lock_wait_timeout = 120
innodb_file_per_table = 0
[mysqldump]
quick
max_allowed_packet = 2M
[mysqld_safe]
log-error = /data/3306/mysql_3306.err
pid-file = /data/3306/mysqld.pid
</code>
vim /data/3307/my.cnf
<code>
[client]
port = 3307
socket = /data/3307/mysql.sock
[mysql]
no-auto-rehash
[mysqld]
user = mysql
port = 3307
socket = /data/3307/mysql.sock
basedir = /application/mysql
datadir = /data/3307/data
open_files_limit = 1024
back_log = 600
max_connections = 800
max_connect_errors = 3000
table_cache = 614
external-locking = FALSE
max_allowed_packet = 8M
sort_buffer_size = 1M
join_buffer_size = 1M
thread_cache_size = 100
thread_concurrency = 2
query_cache_size = 2M
query_cache_limit = 1M
query_cache_min_res_unit = 2K
default_table_type = InnoDB
thread_stack = 192K
transaction_isolation = READ-COMMITTED
tmp_table_size = 2M
max_heap_table_size = 2M
#long_query_time = 1
log_long_format
#log-error = /data/3307/error.log
#log-slow-queries = /data/3307/slow.log
pid-file = /data/3307/mysql.pid
#log-bin = /data/3307/mysql-bin
relay-log = /data/3307/relay-bin
relay-log-info-file = /data/3307/relay-log.info
binlog_cache_size = 1M
max_binlog_cache_size = 1M
max_binlog_size = 2M
expire_logs_days = 7
key_buffer_size = 16M
read_buffer_size = 1M
read_md_buffer_size = 1M
bulk_insert_buffer_size = 1M
myisam_sort_buffer_size = 1M
myisam_max_sort_file_size = 10G
myisam_max_extra_sort_file_size = 10G
myisam_repair_threads = 1
myisam_recover
lower_case_table_names = 1
skip-name-resolve
slave-skip-errors = 1032,1062
replicate-ignore-db=mysql
server-id = 3
innodb_additional_mem_pool_size = 4M
innodb_buffer_pool_size = 32M
innodb_data_file_path = ibdata1:128M:autoextend
innodb_file_io_threads = 4
innodb_thread_concurrency = 8
innodb_flush_log_at_trx_commit = 2
innodb_log_buffer_size = 2M
innodb_log_file_size = 4M
innodb_log_files_in_group = 3
innodb_max_dirty_pages_pct = 90
innodb_lock_wait_timeout = 120
innodb_file_per_table = 0
[mysqldump]
quick
max_allowed_packet = 2M
[mysqld_safe]
log-error = /data/3307/mysql_3307.err
pid-file = /data/3307/mysqld.pid
</code>
vim /data/3306/mysql
<code>
#!/bin/bash
# this scripts is created by swolice
#init
port=3306
mysql_user="root"
mysql_pwd="root"
CmdPath="/application/mysql/bin"
mysql_sock="/data/${port}/mysql.sock"
#startup function
function_start_mysql()
{
if [ ! -e "$mysql_sock" ]; then
printf "Starting MYSQL....\n"
/bin/sh ${CmdPath}/mysqld_safe --defaults-file=/data/${port}/my.cnf 2>&1 >/dev/null &
else
printf "MySQL is running...\n"
exit
fi
}
#stop function
function_stop_mysql()
{
if [ ! -e "$mysql_sock" ]; then
printf "MySQL is stopped....\n"
exit
else
printf "Stoping MySQL....\n"
#{CmdPath}/mysqladmin -u ${mysql_user} -p${mysql_pwd} -S /data/${port}/mysql.sock shutdown
fi
}
#restart funciton
function_restart_mysql()
{
function_stop_mysql
sleep 2
function_start_mysql
}
case $1 in
start)
function_start_mysql
;;
stop)
function_stop_mysql
;;
restart)
function_restart_mysql
;;
*)
printf "Usage: /data/${port}/mysql {start|stop|restart}\n"
esac
</code>
启动mysql的实质是：
mysqld_safe --defaults-file=/data/3306/my.cnf 2>&1 > /dev/null &
mysqladmin -u root -pPassword -S /data/3306/mysql.sock shutdown
chown -R mysql:mysql /data
find /data -type f -name mysql -exec chmod 700 {} \;
find /data -name mysql | xargs chmod 700
/application/mysql/scripts/mysql_install_db --basedir=/application/mysql --datadir=/data/3306/data --user=mysql
/application/mysql/scripts/mysql_install_db --basedir=/application/mysql --datadir=/data/3307/data --user=mysql
初始化数据库的主要目的就是创建基础的数据库我呢见，生成mysql数据库表等。。。
初始化数据库错误处理：
/usr/libexec/mysqld:unknown variable 'table_open_cache=4'
Installaton of system tables failed!
使用错了初始化数据库的命令，用了系统自带的/usr/bin/mysql_install_db出现的错误。
一个主机的多实例的mysql登录只能使用sock登录：
mysql -S /data/3306/mysql.sock -uroot -proot
mysqladmin -uroot -S /data/3306/mysql.sock password 'new password'
远程连接mysql使用方法：
mysql -uroot -proot -P3308 -h 10.0.55.61