What is this error from? - ruby

Question

I have absolutely no idea what I changed. The unicorn configuration has been static for months. And suddenly I start seeing this error - it seems related to something about workers but this is on dev and I have that part disabled in my app for dev. I'm totally stumped as to what happened - some update to unicorn?
EDIT: I should have been more clear. I KNOW it's a route problem. The trouble is, I do not know what is calling /inform. I am not calling this anywhere in my written code. Which means some gem is expecting there to be a resource at /inform, and it appears to be related to Unicorn. But I haven't changed anything to do with Unicorn in over 6 months. Which leads me to believe that some time I ran bundle install brought up a new version of the gem.
Try as I might, I haven't been able to identify what changed and where.
Started POST "/inform" for 192.168.1.9 at 2014-08-08 16:46:01 -0500
ActionController::RoutingError (No route matches [POST] "/inform"):
actionpack (3.2.13) lib/action_dispatch/middleware/debug_exceptions.rb:21:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
railties (3.2.13) lib/rails/rack/logger.rb:32:in `call_app'
railties (3.2.13) lib/rails/rack/logger.rb:16:in `block in call'
activesupport (3.2.13) lib/active_support/tagged_logging.rb:22:in `tagged'
railties (3.2.13) lib/rails/rack/logger.rb:16:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/request_id.rb:22:in `call'
rack (1.4.5) lib/rack/methodoverride.rb:21:in `call'
rack (1.4.5) lib/rack/runtime.rb:17:in `call'
activesupport (3.2.13) lib/active_support/cache/strategy/local_cache.rb:72:in `call'
rack (1.4.5) lib/rack/lock.rb:15:in `call'
actionpack (3.2.13) lib/action_dispatch/middleware/static.rb:63:in `call'
railties (3.2.13) lib/rails/engine.rb:479:in `call'
railties (3.2.13) lib/rails/application.rb:223:in `call'
railties (3.2.13) lib/rails/railtie/configurable.rb:30:in `method_missing'
rack (1.4.5) lib/rack/lint.rb:48:in `_call'
rack (1.4.5) lib/rack/lint.rb:36:in `call'
rack (1.4.5) lib/rack/showexceptions.rb:24:in `call'
rack (1.4.5) lib/rack/commonlogger.rb:33:in `call'
rack (1.4.5) lib/rack/chunked.rb:43:in `call'
rack (1.4.5) lib/rack/content_length.rb:14:in `call'
unicorn (4.8.0) lib/unicorn/http_server.rb:571:in `process_client'
unicorn (4.8.0) lib/unicorn/http_server.rb:658:in `worker_loop'
unicorn (4.8.0) lib/unicorn/http_server.rb:520:in `spawn_missing_workers'
unicorn (4.8.0) lib/unicorn/http_server.rb:140:in `start'
unicorn (4.8.0) bin/unicorn:126:in `<top (required)>'
/usr/local/rvm/gems/ruby-2.0.0-p451/bin/unicorn:23:in `load'
/usr/local/rvm/gems/ruby-2.0.0-p451/bin/unicorn:23:in `<main>'
/usr/local/rvm/gems/ruby-2.0.0-p451/bin/ruby_executable_hooks:15:in `eval'
/usr/local/rvm/gems/ruby-2.0.0-p451/bin/ruby_executable_hooks:15:in `<main>'
I added a fake route to stuff whatever came across into a collection:
Started POST "/inform" for 192.168.1.9 at 2014-08-14 20:48:45 -0500
Processing by ApiController#inform as HTML
WARNING: Can't verify CSRF token authenticity
MONGODB (0.5ms) creative_development['admins'].find({:_id=>nil}).limit(-1)
Redirected to http://192.168.x.x/login
Filter chain halted as :require_login rendered or redirected
Completed 302 Found in 1ms
192.168.1.9 - - [14/Aug/2014 20:48:45] "POST /inform HTTP/1.1" 302 - 0.0150
Of course it halted because whatever this is isn't part of my application and hasn't authenticated. Still no idea what's causing it.