We are attempting to slowly migrate a website over to AWS among other things. We decided the first thing to move was the database. We have some dedicated server with a different hosting provider. We only have one IP. I am having trouble authorizing the ip so that the old server can connect to RDS. It simply hangs for a while while using the mysql cli, then responds:

ERROR 2003 (HY000): Can't connect to MySQL server on 'db.address.us-east-1.rds.amazonaws.com' (110)

It did work on my laptop though. I am not quite sure what is wrong. I have a feeling I don't quite understand CIDR/IP. I simply took the ip address and tacked on /32 at the end. Then I gleaned some information that it also has to do with subnet mask? ifconfig reports: 255.255.255.0

I found a calculator and the IP changed a bit and had /24 at the end. That still didn't work.

One other note... perhaps i dont know enough about the differences between OS. The hosting provider is using centOS, while our development machines are all ubuntu.

Any insight would be extremely helpful! THANKS :)