Nginx - ELB health check fails because of 301

I have set up ELB health check (port 80) on this uri - /healthcheck but the problem is I am getting a 301 because nginx redirects all traffic coming at port 80.

My goal is this -

1. Use a simple html file (my app serves this file) for ELB health check..
2. When I need to take an instance out of rotation, I just use a script to remove this file and so ELB stops sending traffic to this instance.
3. Now I can do a deploy. Once all is done, I create the file again and things return to normal again