SE made a post on lodestone about Balmung having troubles.

We are currently experiencing technical difficulties preventing players from logging in to the Balmung World. The issue is currently under investigation, and new updates will follow as additional information becomes available.

We apologize for any inconvenience this may be causing, and we thank you for your understanding.
http://na.finalfantasyxiv.com/lodest...eca19df4cdba03