I have a Java application that connects to MySQL on an Amazon EC2 (USA east region) instance with JDBC (using official latest Oracle drivers, location specified by IP). It also connects to S3 using Amazon's given SDK.
Problem is, while everything is fast and works great from any server, except for one server at a specific location (let's say LOC-A). Establishing connections in the application time out, or on average, are able to connect 1/10 restarts (but then are really slow). S3 connections error out at the same rate as well. MySQL Workbench hangs 9/10 times fetching results from the database.
The connection is a residential FIOS connection (hardwired from modem to PC). 50MB/s down, 25MB/s, <20ms ping. Computer and modem restarted. Firewall disabled. Latest network drivers. DNS, ARP caches cleared. All privileges for MySQL user for any hostname.
Like I said, any other server works great, this specific computer or network is terrible.
I understand I'm giving very high level information, but the code is stable and no changes were added.
Can anyone recommend next course of action, please? We are starting to suspect (tin-foil-hat-on) deep-packet inspection.