1、再次使用xshell5 远程连接Ubuntu登录MySQL时出现错误。
dba@dba:~$ mysql
mysql: [ERROR] unknown option '--:'
解决思路：
检查mysql是否已经启动
root@dba:/app/mysql/support-files# service mysqld status
● mysqld.service - Mysql Server
Loaded: loaded (/etc/systemd/system/mysqld.service; disabled; vendor preset: enabled)
Active: active (running) since Sat 2019-12-28 00:44:16 EST; 32min ago
mysql启动后检查错误日志
root@dba:/app/mysql/support-files# vim /data/mysql/dba.err
错误日志无关
打开etc/my.cnf，确认是否填错
发现最后一行多打了个“：”，删除后即可。
再次输入mysql，就可以进入mysql。
root@dba:/app/mysql/support-files# mysql
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.28 MySQL Community Server (GPL)
2、创建多个实例时提示：bash: /data/3308/my.cnf: No such file or directory
随后打算安装yum，提示
There are no enabled repos.
Run "yum repolist all" to see the repos you have.
You can enable repos with yum-config-manager --enable <repo>
root@dba:~# yum repolist all
repolist: 0
原因是创建目录是330{7,8,9}写出了330{7.8.9}
root@dba:/etc/systemd/system# chown -R mysql.mysql /data/*
root@dba:/etc/systemd/system# systemctl start mysqld3307.service
root@dba:/etc/systemd/system# systemctl start mysqld3308.service
root@dba:/etc/systemd/system# systemctl start mysqld3309.service
