502 Bad Gateway on Google Compute Engine, Nginx, and Meteor

Question

I built a Meteor app and would like to run it on Google Compute Engine. I followed the guide found here to get a basic instance of my app up and running, changing the disk size/type, the instance type, the disk and instance zones (to both match where I live), and added export METEOR_SETTINGS={ ... } to the second to last line of the startup.sh file.

Everything seemed to work fine, I have the persistent disk and vm instance listed on my Google Cloud dashboard. I created a new firewall rule on my default network to tcp:80 and tcp:443 incoming traffic, and now when I access the instance's external IP address from my browser, I'm shown a 502 Bad Gateway nginx/1.8.0 page (where I'd instead expect the homepage of my Meteor app).

Is there anything in the configuration details in the startup.sh file that I'm missing or should modify? Could there be an issue with how the compute vm instance is communicating with the persistent disk? Frankly I'm far outside of my domain with this type of thing.

Answer 1

After ssh-ing into my instance and dinking around a bit, I called export ROOT_URL='<the_instances_external_ip>' , rather than ' http://localhost ', at which point everything started to work. It's unfortunate how little documentation there is on getting Meteor apps configured and running in production (I only thought to mess with ROOT_URL after searching something unrelated), so hopefully this will at least be helpful for someone else.