问题:在做网站的时候,使用JDBC进行数据库连接的时候,死活连接不上,并出现了标题所示错误。
在服务器上用dbeaver来连接是没有问题的。
解决方法:检查阿里云安全组设置,发现没有把3306开放出去,开放后就可以了
- milliseconds successfully packet server lastmilliseconds successfully packet server communications milliseconds successfully received milliseconds successfully received原因 received packets driver server successfully established connection server server error sqlexception successfully milliseconds packet packets max_allowed_packet