H14 error in heroku - "no web processes running"

Question

error H14 happen while deploying to heroku this is my procfile:

web: gunicorn -w 4 -b 0.0.0.0:$PORT -k gevent main:app

log on heroku:

2017-01-23T10:42:58.904480+00:00 heroku[router]: at=error code=H14 desc="No web processes running" method=GET path="/" host=meetcapstone.herokuapp.com request_id=df88efb5-a81a-4ac0-86dc-4e03d71266bb fwd="81.218.117.137" dyno= connect= service= status=503 bytes=
2017-01-23T10:42:59.009135+00:00 heroku[router]: at=error code=H14 desc="No web processes running" method=GET path="/favicon.ico" host=meetcapstone.herokuapp.com request_id=21cea981-36b0-4410-891f-548bbc29f0ee fwd="81.218.117.137" dyno= connect= service= status=503 bytes=

requirements:

Flask==0.11.1
passlib==1.7.0
SQLAlchemy==1.1.5
Werkzeug==0.11.15
gunicorn==19.0.0
gevent==1.2.1

Answer 1

The issue here is that you're not running any web dynos. You can tell Heroku to do this via:

$ heroku ps:scale web=1

This will force Heroku to spin up a web dyno, thereby executing your gunicorn command.

Answer 2

After 3 hours of debugging, I've figured out why my app was causing this error:

1. My Procfile was incorrectly cased
2. gunicorn wasn't installed in my venv

IMO, this error should be raised on Heroku's end. As a beginner, this sort of error is difficult to trace.

Update: To clarify, Procfile is correctly cased and procfile is not correctly cased. It should start with a capital "P".

More info on dyno configuration – more on initializing your heroku app.

Answer 3

I ran into the same problem but from a different cause. I had the hobby tier, but then canceled it and reverted back to the free tier. Doing this caused the error and how I fixed it was just re running the command from the cli:

heroku ps:scale web=1