CentOS同时安装mysql8.0（替换）

系统里已经有mysql5.7，但是由于特殊要求需要再安装一个8.0版本

1、下载包
注意：安装包要匹配linux系统的cglib版本！！！否则初始化会报错

./mysqld: /lib64/libstdc++.so.6: version `CXXABI_1.3.11' not found (required by ./mysqld)
./mysqld: /lib64/libstdc++.so.6: version `CXXABI_1.3.8' not found (required by ./mysqld)
./mysqld: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.22' not found (required by ./mysqld)
./mysqld: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.20' not found (required by ./mysqld)
./mysqld: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by ./mysqld)
./mysqld: /lib64/libstdc++.so.6: version `CXXABI_1.3.9' not found (required by ./mysqld)
./mysqld: /lib64/libc.so.6: version `GLIBC_2.28' not found (required by ./mysqld)
./mysqld: /lib64/libc.so.6: version `GLIBC_2.25' not found (required by /usr/local/mysql8/bin/../lib/private/libcrypto.so.1.1)
./mysqld: /lib64/libc.so.6: version `GLIBC_2.28' not found (required by /usr/local/mysql8/bin/../lib/private/libprotobuf-lite.so.3.19.4)
./mysqld: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.20' not found (required by /usr/local/mysql8/bin/../lib/private/libprotobuf-lite.so.3.19.4)
./mysqld: /lib64/libstdc++.so.6: version `CXXABI_1.3.9' not found (required by /usr/local/mysql8/bin/../lib/private/libprotobuf-lite.so.3.19.4)
./mysqld: /lib64/libstdc++.so.6: version `CXXABI_1.3.8' not found (required by /usr/local/mysql8/bin/../lib/private/libprotobuf-lite.so.3.19.4)
./mysqld: /lib64/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by /usr/local/mysql8/bin/../lib/private/libprotobuf-lite.so.3.19.4)

mysql8数据库目录结构
MySQL Binary目录：/usr/local/mysql8
MySQL Data目录：/data/mysql8
MySQL Backup目录：/backup/mysql8

groupadd -g 1003 mysql8
useradd -r -s /sbin/nologin -g mysql8 -u 1003 -d /usr/local/mysql8/ mysql8

chown -R mysql8:mysql8 /usr/local/mysql8/
chown -R mysql8.mysql8 /data/mysql8
chown -R mysql8.mysql8 /backup/mysql8

2、初始化

cd /usr/local/mysql8/bin
./mysqld --initialize --user=mysql8 --basedir=/usr/local/mysql8 --datadir=/data/mysql8

3、配置my.cnf（好像只能有一个my.cnf文件）
将mysql都换成mysql8

[mysqld]
basedir = /usr/local/mysql8
datadir = /data/mysql8
socket = /tmp/mysql8.sock
user = mysql8
port = 3306
character_set_server = utf8
explicit_defaults_for_timestamp=true
log_timestamps=SYSTEM
#server-id=1
tmpdir = /tmp
symbolic-links=0
#关闭binlog
skip-log-bin

#数据库数据文件参数

innodb_data_file_path = ibdata1:10M:autoextend
innodb_file_per_table = ON

#数据库内存参数

key_buffer_size = 128M
innodb_buffer_pool_size = 2048M

#数据库线程数参数

thread_cache_size = 600
innodb_thread_concurrency = 4

#innodb日志文件参数

innodb_log_buffer_size = 16M
innodb_log_file_size = 256M
innodb_log_files_in_group = 3

#文件描述符限制

open_files_limit = 10240

#数据库bin log参数

#log-bin=mysql-bin
#binlog-format = Row
#binlog_cache_size = 4M
#max_binlog_size = 256M
#binlog-ignore-db=information_schema
#binlog-ignore-db=mysql
#binlog-ignore-db=performance_schema
#binlog-ignore-db=sys
#replicate_wild_do_table=test.%
#replicate-do-db=test
#replicate-ignore-db=mysql
#log-slave-updates
#slave-skip-errors=all
#slave-net-timeout=60
#relay-log=mysqldb02-relay-bin
#master-info-repository=table
#relay-log-info-repository=table

#数据库表缓存参数

table_open_cache = 1000
table_definition_cache = 700

#查询缓存参数

#query_cache_type = OFF
#query_cache_size = 0
#query_cache_limit = 0

tmp_table_size = 512M
sort_buffer_size = 2M
join_buffer_size = 2M
read_buffer_size = 1M
read_rnd_buffer_size = 16M

#数据库connect参数

max_connections = 2000
back_log = 100
max_connect_errors = 1000
max_allowed_packet = 32M

#数据库慢查询日志参数

slow_query_log = ON
slow_query_log_file = /data/mysql8/mysqldb01-slow.log
long_query_time = 10
log_queries_not_using_indexes = ON

secure_file_priv = /tmp

# 默认使用“mysql_native_password”插件认证
default_authentication_plugin=mysql_native_password

[mysqld_safe]
log-error = /data/mysql8/error.log
pid-file = /data/mysql8/mysql.pid

[mysqldump]
quick
max_allowed_packet = 16M

[client]
port=3306
socket=/tmp/mysql8.sock

4、配置mysql服务/etc/init.d/mysqld8
将mysql都换成mysql8

5、编辑mysqld8.service
/usr/lib/systemd/system/mysqld8.service

[Unit]
Description=MySQL 8.0
SourcePath=/etc/init.d/mysqld8
After=network.target
After=syslog.target
Before=shutdown.target

[Service]
User=mysql8
Group=mysql8
Type=forking
ExecStart=/etc/init.d/mysqld8 start
ExecStop=/etc/init.d/mysqld8 stop
ExecReload=/etc/init.d/mysqld8 restart
LimitNOFILE = 65535

[Install]
WantedBy=multi-user.target

6、ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.
必须修改mysql初始密码

alter user 'root'@'localhost' identified by '123456';

7、导入数据
建数据库，建用户
源数据库导出

mysqldump -u root -p --databases commodity shopping --lock-tables > /tmp/all.sql

本地数据库导入

mysql -u root -p
source /tmp/all.sql

8、更新

./mysqld --skip-grant-tables --user=mysql --upgrade=FORCE
2022-08-05T09:46:21.091800+08:00 0 [Warning] [MY-011070] [Server] 'Disabling symbolic links using --skip-symbolic-links (or equivalent) is the default. Consider not using this option as it' is deprecated and will be removed in a future release.
2022-08-05T09:46:21.091872+08:00 0 [Warning] [MY-010143] [Server] Ignoring user change to 'mysql' because the user was set to 'mysql8' earlier on the command line
2022-08-05T09:46:21.092998+08:00 0 [Warning] [MY-010101] [Server] Insecure configuration for --secure-file-priv: Location is accessible to all OS users. Consider choosing a different directory.
2022-08-05T09:46:21.093071+08:00 0 [Warning] [MY-010918] [Server] 'default_authentication_plugin' is deprecated and will be removed in a future release. Please use authentication_policy instead.
2022-08-05T09:46:21.093107+08:00 0 [System] [MY-010116] [Server] /usr/local/mysql8/bin/mysqld (mysqld 8.0.30) starting as process 31843
2022-08-05T09:46:21.094494+08:00 0 [Warning] [MY-013242] [Server] --character-set-server: 'utf8' is currently an alias for the character set UTF8MB3, but will be an alias for UTF8MB4 in a future release. Please consider using UTF8MB4 in order to be unambiguous.
2022-08-05T09:46:21.115181+08:00 0 [Warning] [MY-013907] [InnoDB] Deprecated configuration parameters innodb_log_file_size and/or innodb_log_files_in_group have been used to compute innodb_redo_log_capacity=805306368. Please use innodb_redo_log_capacity instead.
2022-08-05T09:46:21.117874+08:00 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
2022-08-05T09:46:22.841355+08:00 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
2022-08-05T09:46:27.765000+08:00 4 [System] [MY-013381] [Server] Server upgrade from '80030' to '80030' started.
2022-08-05T09:47:08.509184+08:00 4 [System] [MY-013381] [Server] Server upgrade from '80030' to '80030' completed.
2022-08-05T09:47:08.928553+08:00 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed.
2022-08-05T09:47:08.928604+08:00 0 [System] [MY-013602] [Server] Channel mysql_main configured to support TLS. Encrypted connections are now supported for this channel.
2022-08-05T09:47:08.951677+08:00 0 [System] [MY-011323] [Server] X Plugin ready for connections. Socket: /tmp/mysqlx.sock
2022-08-05T09:47:08.951727+08:00 0 [System] [MY-010931] [Server] /usr/local/mysql8/bin/mysqld: ready for connections. Version: '8.0.30'  socket: '/tmp/mysql8.sock'  port: 0  MySQL Community Server - GPL.

9、问题
一个CentOS上既有mysql5.7，又有mysql8.0
配置文件需要改名my.cnf、my.cnf.57
端口都是3306，所以只能起一个，如需用另一个要改名配置文件切换