Tomcat7 MySQL Connection Error

I'm facing a perplexing problem. I've completed a jsf web app that utlizes hibernate and infinispan with Tomcat7 and tomcat-jdbc-pool as the connection pool provider.

It is being deployed to a Linode cluster w/ 2 nodes -- one database server and one production server.

I can run the app on my local environment using the exact same copy of Tomcat7 (I literally tarred the tomcat directory and promoted it to the server to debug this error) -- even when connected to the live database instance. Everything runs fine.

When I attempt to run the application from the production server I get a MySQLIO error:

Caused by: java.net.ConnectException: Connection refused

Looking further up in the logs i see:

The last packet sent successfully to the server was 1 milliseconds ago. The driver has not received any packets from the server. com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

I can connect from the command line on the prodapp server just fine -- even using tcp:

mysql -h db01 -u user -p --protocol=tcp

But it just won't work running inside the Tomcat container. I've tried all kinds of things but I'm really stumped. It just seems strange that I can connect to the database server using the same copy of Tomcat7 locally but when deployed to production the same copy of tomcat7 can't connect -- even though I can connect from the command line on that production server ... I'm stumped.

Any help is greatly appreciated.

EDIT: Solved my problem after wasting too much good life on it. The answer was I'm stupid. Thanks to everyone who tried to help. I have the app moded w/ a dev and live mode and the connection pool was reading the dev mode this whole time. What really made it confusing is that the sessionfactory was moded to live so it would actually reach the live database and initialize a connection when it started up so i could开发者_StackOverflow社区 see it connecting (and running meta data queries in the mysql log), but when it actually went to grab a connection from infinispan it blew up. Oh well -- at least it's working now. Thanks again.

If you're connecting to your MySQL database server from a different box, then you need to explicitly grant permission for that user account to connect from that IP.

You can do this whilst in the command line:

GRANT ALL PRIVILEGES ON *.* TO 'username'@'ip_address'

EDIT: Granting all permissions on all tables generally isn't required, be specific about what permissions you want to grant (http://dev.mysql.com/doc/refman/5.1/en/grant.html)

To see what permissions you currently have:

USE mysql;
SELECT * FROM users;

My apologies if I'm patronising you, just that this is the most common problem that I come across.