Hosting a rails web app on heroku; no recent code changes but about 2 days ago the application started reporting constant H31 misdirect errors. After looking into the documentation, since the application was still accessible I moved on.
The next day users from some of the subdomains could not access the application while others could. The application uses a wildcard certificate and we are behind a WAF. The first thing I tried was checking firewall logs and nothing was showing as blocked. I turned off the firewall and connected the domain directly to the application and still received the H31 stream, after 15 minutes of no change i re-enabled the firewall.
Reached out to the firewall and they said that their logs only showed upstream prematurely closed connection while reading response header
At this point they suggested the issue was most likely on the Heroku DNS servers, so I'm waiting for a response at this point.
Is there anything I can do in the heroku environment that would change this or am I stuck waiting for a response?