一. 准备工作 1 删除本地CentOS7中的mariadb：
查看系统中是否已安装 mariadb 服务：
rpm -qa | grep mariadb
或
yum list installed | grep mariadb
如果已安装则删除 mariadb及其依赖的包：
yum -y remove mariadb-libs-5.5.44-2.el7.centos.x86_64
关闭防火墙：
firewall-cmd --state #查看防火墙状态
systemctl stop firewalld.service #关闭防火墙
systemctl is-enabled firewalld.service;echo $? #查看防火墙是否开机自启
systemctl disable firewalld.service #禁止防火墙开机启动
MySQL依赖于libaio 库，安装libaio
yum search libaio
yum install libaio
2.下载安装包
mkdir /data
cd /data/
yum -y install wget
wget https://cdn.mysql.com//Downloads/MySQL-5.7/mysql-5.7.20-linux-glibc2.12-x86_64.tar.gz
3. 解压、重命名
tar -zxvf mysql-5.7.20-linux-glibc2.12-x86_64.tar.gz -C /data
mv /data/mysql-5.7.20-linux-glibc2.12-x86_64/ /data/mysql57
mkdir mysql #数据目录与安装目录分离，便于以后MySQL升级
二. 安装MySQL 1.添加用户和组groupadd mysql
useradd mysql -g mysql
2.配置文件/etc/my.cnf
主要参数及取值如下：
（相关取值，请根据实际环境做调整，如内存配置参数等）
####### [client] socket = /data/mysql/data/mysql.sock default-character-set=utf8mb4 #loose-local-infile=0 [mysqld] log_bin_trust_function_creators=1 secure_file_priv='/tmp' ########dir settings######## basedir = /data/mysql57 datadir = /data/mysql/data pid-file = /data/mysql/data/mysql.pid socket = /data/mysql/data/mysql.sock tmpdir = /data/mysql/tmp log-bin = /data/mysql/mysql_log/mysql-bin log-error = /data/mysql/mysql_log/mysql.err general_log_file=/data/mysql/mysql_log/mysql.genlog slow_query_log_file = /data/mysql/mysql_log/mysql_slow_new.log relay_log = /data/mysql/mysql_log/relay.log ########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" server-id = 2022 port = 3306 character-set-server=utf8mb4 collation_server=utf8mb4_unicode_ci lower_case_table_names = 0 skip_name_resolve = 1 #max_connect_errors = 1000 max_connections = 2000 thread_cache_size=256 #thread_stack= 262144 #back_log=80 max_allowed_packet = 134217728 event_scheduler = 1 local-infile=0 # lower_case_table_names = 1 explicit_defaults_for_timestamp = 1 expire_logs_days = 15 log_bin_trust_function_creators =1 ####.frm/.ibd files qty related open_files_limit=65535 innodb_open_files=65535 table_open_cache=65535 table_definition_cache=65535 #### seesion buffer related read_buffer_size = 262144 read_rnd_buffer_size = 524288 sort_buffer_size = 8388608 join_buffer_size = 8388608 ####memory table size tmp_table_size =67108864 max_heap_table_size=67108864 ####timeout interactive_timeout = 1800 wait_timeout = 1800 # connect_timeout=10 ########slow query ######## slow_query_log = 1 log_slow_slave_statements = 1 log_queries_not_using_indexes = 1 log_throttle_queries_not_using_indexes = 10 long_query_time = 1 #min_examined_row_limit = 10000 ########innodb settings######## innodb_buffer_pool_size = 193273528320 innodb_buffer_pool_instances = 16 innodb_buffer_pool_dump_pct = 40 innodb_lru_scan_depth = 2048 innodb_page_cleaners = 16 #innodb_purge_threads = 4 innodb_sort_buffer_size = 67108864 #innodb_file_per_table = 1 #innodb_flush_log_at_trx_commit = 1 innodb_undo_log_truncate = 1 innodb_undo_tablespaces = 3 innodb_max_undo_log_size = 2147483648 innodb_purge_rseg_truncate_frequency = 128 innodb_log_file_size = 1073741824 innodb_log_files_in_group = 3 innodb_log_buffer_size = 16777216 innodb_flush_method = O_DIRECT innodb_flush_neighbors = 0 innodb_print_all_deadlocks = 1 innodb_strict_mode = 1 #innodb_lock_wait_timeout = 50 innodb_io_capacity = 32768 innodb_io_capacity_max = 65536 innodb_thread_concurrency = 32 innodb_write_io_threads = 8 innodb_read_io_threads = 8 ########replication settings######## master_info_repository = TABLE relay_log_info_repository = TABLE gtid_mode = on enforce_gtid_consistency = 1 binlog_gtid_simple_recovery=1 relay_log_recovery = 1 slave-parallel-type = LOGICAL_CLOCK slave-parallel-workers = 16 slave_transaction_retries=128 slave_preserve_commit_order=1 log_slave_updates=1 binlog_format = ROW log_timestamps=system binlog_rows_query_log_events = 1 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 = 1 #rpl_semi_sync_master_timeout = 5000 #rpl_semi_sync_slave_enabled = 1 [mysqldump] quick
说明：
请一定记得上面 配置模板文件中的server-id 参数一定要修改。
否则在配置 主从复制，或者MHA时会报错。
例如错误信息 ：