本次进行MySQL5.7版本的安装，关于MySQL版本选择、官网下载地址、相关系统配置等操作可以参照之前的博文,本文就不在赘述咯。可以参考历史文章处理，下面直奔主题，进行相关安装工作。

总体安装步骤概述如下：

操作系统等相关配置设置

安装依赖包

创建用户

修改配置文件、创建相关数据目录、日志目录等并授权

运行安装命令，启动数据库

配置环境变量、服务等

因为我之前已经安装了MySQL5.6，本次继续在同一台机器上安装一个MySQL5.7版本的实例，相关配置及依赖包等操作之前已处理完毕，

现在就接着后续操作进行了。如果首次安装，需先进行配置。详情见https://www.jianshu.com/p/b0a0fbe161fd

一、准备工作

安装必要依赖包

yum install -y libaio

创建用户

groupadd mysql

useradd -r -g mysql mysql

上传安装包至 /usr/local ,如上传至其他路径，以下操作过程中注意修改路径，或者在/usr/local目录创建软连接

解压

tar -zxvf mysql-5.7.22-linux-glibc2.12-x86_64.tar.gz

创建软连接

ln -s mysql-5.7.22-linux-glibc2.12-x86_64 /usr/local/mysql5.7

修改目录权限

cd /usr/local

chown -R mysql:root mysql5.7

二、创建相关数据目录、日志目录、配置文件等并授权

创建相关目录

mkdir -p /data/mysql/mysql3307/{data,logs,etc,tmp}

配置文件

vi /data/mysql/mysql3307/etc/my3307.cnf

可以参考如下配置文件，注意根据自己的环境修改相关配置

[mysqld] ########basic settings######## server-id = 463307 port = 3307 user = mysql character_set_server=utf8mb4 skip_name_resolve = 1 max_connections = 800 max_connect_errors = 1000 datadir = /data/mysql/mysql3307/data #根据实际情况修改,建议和程序分离存放 transaction_isolation = READ-COMMITTED explicit_defaults_for_timestamp = 1 join_buffer_size = 512M tmp_table_size = 512M tmpdir = /data/mysql/mysql3307/tmp pid-file = /data/mysql/mysql3307/tmp/mysqld3307.pid socket = /data/mysql/mysql3307/tmp/mysql3307.sock max_allowed_packet = 128M sql_mode = "STRICT_TRANS_TABLES,NO_ENGINE_SUBSTITUTION,NO_ZERO_DATE,NO_ZERO_IN_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER" interactive_timeout = 1800 wait_timeout = 1800 read_buffer_size = 16M read_rnd_buffer_size = 32M sort_buffer_size = 32M language = /usr/local/mysql5.7/share/english ## 以后版本将取消该参数 ########log settings######## log_error =/data/mysql/mysql3307/logs/mysqld3307.log slow_query_log = 1 slow_query_log_file = /data/mysql/mysql3307/logs/slow.log log_queries_not_using_indexes = 1 log_slow_admin_statements = 1 log_slow_slave_statements = 1 log_throttle_queries_not_using_indexes = 10 expire_logs_days = 3 long_query_time = 2 min_examined_row_limit = 100 ########replication settings######## master_info_repository = TABLE relay_log_info_repository = TABLE log_bin = /data/mysql/mysql3307/logs/mysql_binlog sync_binlog = 1 gtid_mode = on enforce_gtid_consistency = 1 log_slave_updates binlog_format = row relay_log = /data/mysql/mysql3307/logs/relay.log relay_log_recovery = 1 binlog_gtid_simple_recovery = 1 slave_skip_errors = ddl_exist_errors ########innodb settings######## innodb_page_size = 8192 innodb_buffer_pool_size = 1G #根据实际情况修改 innodb_buffer_pool_instances = 8 innodb_buffer_pool_load_at_startup = 1 innodb_buffer_pool_dump_at_shutdown = 1 innodb_lru_scan_depth = 2000 innodb_lock_wait_timeout = 5 innodb_io_capacity = 4000 innodb_io_capacity_max = 8000 innodb_flush_method = O_DIRECT innodb_file_format = Barracuda innodb_file_format_max = Barracuda innodb_log_group_home_dir = /data/mysql/mysql3307/logs/ #根据实际情况修改 innodb_undo_directory = /data/mysql/mysql3307/logs/ #根据实际情况修改 innodb_undo_logs = 128 innodb_undo_tablespaces = 3 innodb_flush_neighbors = 1 innodb_log_file_size = 512M #根据实际情况修改 innodb_log_buffer_size = 16777216 innodb_purge_threads = 4 innodb_large_prefix = 1 innodb_thread_concurrency = 64 innodb_print_all_deadlocks = 1 innodb_strict_mode = 1 innodb_sort_buffer_size = 67108864 ########semi sync replication settings######## plugin_dir=/usr/local/mysql5.7/lib/plugin #根据实际情况修改 plugin_load = "rpl_semi_sync_master=semisync_master.so;rpl_semi_sync_slave=semisync_slave.so" loose_rpl_semi_sync_master_enabled = 1 loose_rpl_semi_sync_slave_enabled = 1 loose_rpl_semi_sync_master_timeout = 5000 [mysqld-5.7] innodb_buffer_pool_dump_pct = 40 innodb_page_cleaners = 4 innodb_undo_log_truncate = 1 innodb_max_undo_log_size = 1G innodb_purge_rseg_truncate_frequency = 128 binlog_gtid_simple_recovery=1 log_timestamps=system transaction_write_set_extraction=MURMUR32 show_compatibility_56=on

授权

chown -R mysql:mysql /data/mysql/mysql3307

三、安装及启动

1.指定本实例的配置文件进行安装

# 建议写全路径运行命令进行安装

/usr/local/mysql5.7/bin/mysqld --defaults-file=/data/mysql/mysql3307/etc/my3307.cnf --initialize --user=mysql

注意：mysql5.7安装后默认会产生一个临时密码，存放于错误日志里，可以查看错误日志进行查看

# 查看日志

vim /data/mysql/mysql3307/logs/mysqld3307.log

此时可以看到临时密码，并查看是否有错误产生

如果不想产生临时密码，可以运行如下命令进行操作，建议使用initialize产生随机密码（下面的语句只是科普使用，无需执行）

/usr/local/mysql5.7/bin/mysqld --defaults-file=/data/mysql/mysql3307/etc/my3307.cnf --initialize-insecure --user=mysql 即：使用--initialize生成随机密码，使用--initialize-insecure生成空密码。

注意：如果安装过程中出现错误，需要将 datadir及 logs下对应的文件删除，并将错误原因查出解决后再运行安装命令，否则将无法再次安装。

2. 启动MySQL实例

#启动数据库，并在后台运行（执行下面命令时多次回车，专为小白而备注）