heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" #Heroku

2021-09-23T16:28:21.498473+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=obscure-escarpment-7xxx2.herokuapp.com request_id=79818b0b-6f0b-4ab9-9bf4-5be938b9e177 fwd="153.246.214.88" dyno= connect= service= status=503 bytes= protocol=https
2021-09-23T16:28:21.890623+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=obscure-escarpment-7xxx2.herokuapp.com request_id=e6cb1a7f-3a21-47aa-a199-622feea5aae6 fwd="153.246.214.88" dyno= connect= service= status=503 bytes= protocol=https

↑クラッシュした事実だけが記載されている。

heroku run consoleで原因が見つかるかも。

% heroku run console
Running console on ⬢ obscure-escarpment-76252... done
 ›   Error: Cannot run more than 1 Free size dynos.
 ›
 ›   Error ID: cannot_run_above_limit
 ›   See https://devcenter.heroku.com/articles/dyno-types#default-scaling-limits for more information.