MySQL 多实例的安装

Step 1 . 准备工作

关闭防火墙; 安装 MySQL依赖于libaio 库；下载，解压，重命名 MySQL的执行文件；新建用户组和用户等准备工作在此不再赘述。

可执行文件目录为 /data/mysql57

添加用户和组的指令

groupadd mysql

useradd mysql -g mysql

Step 2 . 添加环境变量

在/etc/profile文件中，追加 PATH=${PATH}:/data/mysql57/bin/

保存后，如需要立即生效，可执行 source /etc/profile 。

step 3 . 创建目录并授权

在data根目录下执行

mkdir -p mysql3306/data mysql3306/mysql_log mysql3306/tmp mysql3307/data  mysql3307/mysql_log  mysql3307/tmp mysqld_multi/log

创建记录log的文件，此步骤不可少。

touch /data/mysql3306/mysql_log/mysql3306.err

touch /data/mysql3307/mysql_log/mysql3307.err

赋予目录和文件权限

chown -R mysql.mysql mysql3* mysqld_multi

在本测试案例中，mysql57是从其它服务上copy来的，不是直接下载解压的，所以多了下面的两步授权操作。

chmod -R  /data/mysql57/bin

chmod -R  /data/mysql57/support-files

step 4 . 编辑my.cnf

[client]

host=localhost

socket = /tmp/mysql.sock

default-character-set=utf8mb4

#loose-local-infile=

[mysqld]

user=mysql

log_bin_trust_function_creators=

secure_file_priv='/tmp'

########server setting#######

sql_mode = "ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"

character-set-server=utf8mb4

collation_server=utf8mb4_unicode_ci

lower_case_table_names =

skip_name_resolve =

#max_connect_errors =

max_connections =

thread_cache_size=

#thread_stack=

#back_log=

max_allowed_packet =

event_scheduler =

local-infile=

#lower_case_table_names =

explicit_defaults_for_timestamp =

expire_logs_days =

log_bin_trust_function_creators =

####.frm/.ibd files qty related

open_files_limit=

innodb_open_files=

table_open_cache=

table_definition_cache=

#### seesion buffer related

read_buffer_size =

read_rnd_buffer_size =

sort_buffer_size =

join_buffer_size = 

####memory table size

tmp_table_size =

max_heap_table_size=

####timeout

interactive_timeout =

wait_timeout =

# connect_timeout=

########slow query ########

slow_query_log =

log_slow_slave_statements =

#log_queries_not_using_indexes =

log_throttle_queries_not_using_indexes =

long_query_time =

#min_examined_row_limit = 

########innodb settings########

innodb_buffer_pool_size =

innodb_buffer_pool_instances =

innodb_buffer_pool_dump_pct =

innodb_lru_scan_depth =

innodb_page_cleaners =

#innodb_purge_threads =

innodb_sort_buffer_size =

#innodb_file_per_table =

#innodb_flush_log_at_trx_commit = 

innodb_undo_log_truncate =

innodb_undo_tablespaces =

innodb_max_undo_log_size =

innodb_purge_rseg_truncate_frequency = 

innodb_log_file_size =

innodb_log_files_in_group =

innodb_log_buffer_size =

innodb_flush_method = O_DIRECT

innodb_flush_neighbors =

innodb_print_all_deadlocks = 

innodb_strict_mode =

#innodb_lock_wait_timeout = 

innodb_io_capacity =

innodb_io_capacity_max =

innodb_thread_concurrency =

innodb_write_io_threads =

innodb_read_io_threads = 

########replication settings########

master_info_repository = TABLE

relay_log_info_repository = TABLE

gtid_mode = on

enforce_gtid_consistency =

binlog_gtid_simple_recovery=

relay_log_recovery = 

slave-parallel-type = LOGICAL_CLOCK

slave-parallel-workers =

slave_transaction_retries=

slave_preserve_commit_order=

log_slave_updates=

binlog_format = ROW

log_timestamps=system

binlog_rows_query_log_events =

binlog_row_image='full'

slave_skip_errors = ddl_exist_errors

########semi sync replication settings########

##plugin_dir=/data/mysql/plugin/

#plugin_load = "rpl_semi_sync_master=semisync_master.so;rpl_semi_sync_slave=semisync_slave.so"

#rpl_semi_sync_master_enabled =

#rpl_semi_sync_master_timeout =

#rpl_semi_sync_slave_enabled = 

[mysqld_multi]

mysqld = /data/mysql57/bin/mysqld_safe

mysqladmin = /data/mysql57/bin/mysqladmin

log = /data/mysqld_multi/log/mysqld_multi.log

[mysqld3306]

basedir = /data/mysql57

mysqladmin=mysqladmin

datadir=/data/mysql3306/data

port=

server_id=

socket= /tmp/mysql_3306.sock

tmpdir = /data/mysql3306/tmp

pid-file = /data/mysql3306/mysql_log/mysql3306.pid

slow_query_log_file = /data/mysql3306/mysql_log/mysql3306_slow_new.log

log-error = /data/mysql3306/mysql_log/mysql3306.err

general_log_file= /data/mysql3306/mysql_log/mysql3306.genlog

log-bin = /data/mysql3306/mysql_log/mysql3306_bin

relay_log = /data/mysql3306/mysql_log/relay3306.log

innodb_buffer_pool_size = 90G

innodb_buffer_pool_instances = 

[mysqld3307]

basedir = /data/mysql57

mysqladmin=mysqladmin

datadir=/data/mysql3307/data

port=

server_id=

socket= /tmp/mysql_3307.sock

tmpdir = /data/mysql3307/tmp

pid-file = /data/mysql3307/mysql_log/mysql3307.pid

slow_query_log_file = /data/mysql3307/mysql_log/mysql3307_slow_new.log

log-error = /data/mysql3307/mysql_log/mysql3307.err

general_log_file= /data/mysql3307/mysql_log/mysql3307.genlog

log-bin = /data/mysql3307/mysql_log/mysql3307_bin

relay_log = /data/mysql3307/mysql_log/relay3307.log

innodb_buffer_pool_size = 90G

innodb_buffer_pool_instances = 

[mysqldump]

quick

step 5 . 初始化实例

初始化3306端口的实例，注意产生的临时密码。

/data/mysql57/bin/mysqld --defaults-file=/etc/my.cnf --initialize --user=mysql --basedir=/data/mysql57  --datadir=/data/mysql3306/data

初始化3307端口的实例，注意产生的临时密码。

/data/mysql57/bin/mysqld --defaults-file=/etc/my.cnf --initialize --user=mysql --basedir=/data/mysql57  --datadir=/data/mysql3307/data

step 6 . 复制生成mysqld_multi并添加到开机启动

cp /data/mysql57/support-files/mysqld_multi.server /etc/init.d/mysqld_multi

chkconfig  --add mysqld_multi

step 7 . 多实例Mysqld的开启

开启全部实例

mysqld_multi start

查看开启情况（查看全部实例状态）

mysqld_multi report

开启指定实例

开启/etc/my.cnf中[mysqld3306]其中mysqld后面的数字为标签，例如3306标签

mysqld_multi start

同样开启3307标签实例

mysqld_multi start

（注意：此处没有说通过 mysqld_multi stop 命令进行关闭实例，为什么不说，因为命令无效。Step 9 的操作会让它变成有效）

step 8 . 第一次登入实例，修改root账号密码

多实例登入需指定 socket 参数

本测试3306实例登入的方式为：

mysql  -S /tmp/mysql_3306.sock -uroot --port  -p

step 9 . 赋予通过mysqld_multi stop关闭实例的权限。

关闭实例需要配置root用户及密码，修改 /etc/my.cnf文件。

在 [client] 位置添加

user=root

password=密码

因为文件中需要保留账号密码，有安全风险。实际环境中要不要如此设置，还需根据具体情况和安全要求而定。

经过以上步骤的操作，此服务器成功安装了2个MySQL实例，一个Port为3306，另一个Port为3307

感谢：以上文档在同事Fly Chen的基础梳理完成。