Where I work, we have a single development server, and a single production server that we manage on-site. When I try to connect remotely to the MySQL on the development server, I get this error:
ERROR 2003 (HY000): Can't connect to MySQL server on '***' (113)
However, I can successfully connect remotely to MySQL on the production server.
Both servers have identical configuration files. (/etc/my.cnf)
nmap -p 3306 server-name shows that port 3306 is open on production, but closed on development, but
iptables -L -n shows the same rules on both servers, and neither of them have a rule at all for port 3306.
I don't know much about iptables, so I'm wondering how it's possible that port 3306 is open on production, but there isn't a rule for it. Can anyone help me understand what it happening here?
(I've also verified that the MySQL user I'm using is allowed to connect from any host.)