Heroku email from today:
When an app is migrated to the new infrastructure, its default [
appname.herokuapp.com], DNS records, and any [
haiku.herokudns.com] custom domain records are modified to point to the IP addresses of the new routing infrastructure. For a period of 24-48 hours, the app is accessible via both the new and old routing infrastructure. When the migration completes, the app will no longer be accessible via the old routing infrastructure and all traffic must flow via the new infrastructure. Requests for an app sent to the old infrastructure will result in error code: H31 Misdirected Request.
To get correct and future-proof DNS targets for custom domains associated with your Heroku apps, you can run
heroku domainsand compare the DNS target in the output to the CNAME target that you’ve configured with your DNS provider. If the DNS targets don’t match, you need to update your DNS configuration to point to the DNS targets provided by Heroku.
I’ve done the above. This breaks the workaround to get free SSL from cloudflare to work with Heroku (because of the move away from *herokuapp.com, which enabled the workaround in the first place). So now one has to upload a cloudflare certificate by using Heroku SSL (which one can only use on paid dynos)
Rest of the email:
If you have any SSL Endpoints associated to your app, you can verify the DNS by following this step from the SSL Endpoint setup documentation. Please note that the SSL Endpoint add-on is deprecated and will be removed starting July 31, 2021. All existing and new Heroku applications should use Heroku SSL, which includes [Automated Certificate Management (ACM)].
Anyone with a workaround to make free Cloudflare SSL work on free heroku dynos?