Rails - Invalid Authenticity Token After Deploy

Question

We\'re using EngineYard Cloud to deploy our Ruby on Rails application. We are running Rails v2.3.3.

EngineYard Cloud deploys to AWS instances in a manner similar to

Answer 1

ANSWER: After extensive work by EngineYard (they're awesome!) they were able to diagnose the issue. The root cause of this issue is a bug with mongrel clusters. Mongrel doesn't seem to see the first post request after being started. EngineYard did extensive work to diagnose this:

There doesn't appear to be anything in your code causing the issue and I have found people outside of our environment that have experienced the bug as well (http://www.thought-scope.com/2009/07/mongrelcluster-rails-23x-bad-post.html). I suppose a lot of people don't see it because the first request to a site generally isn't a post or they chalk it up to flukes.

[There is a potential workaround using CURL.] The curl work around would do a simple GET request to each of your mongrels on the server to prime them so to speak. You could do this with capistrano, but that won't work if you deploy via the dashboard. You can find a short section on deploy hooks we have built into the infrastructure here: https://cloud-support.engineyard.com/faqs/overview/getting-started-with-engine-yard-cloud

Adding a simple run curl http://localhost:500x > /dev/null should work (where x is the port you have 5000-50005 on your current setup).

We have addressed the issue by switching our stack from Mongrel to Passenger, but apparently, a fix for Mongrel is in the works. Hopefully, this helps someone who sees this same strange issue.