The issue affects --dry-run functionality for all Certbot versions below 0.32.0 .
There are two issues:
- ACME v2 - Scheduled deprecation of unauthenticated resource GETs for acme-staging-v02.api.letsencrypt.org from today, requiring Certbot 0.29.0 or newer.
-
A related
Content-Typebug in Certbot when downloading the certificate via POST-as-GET, requiring Certbot 0.32.0 or higher.
You will need to upgrade to Certbot 0.32.0 or higher to be able to use --dry-run again.
See https://certbot.eff.org/ for instructions on upgrading.
This issue doesn’t affect real certificate renewals. It only affects --dry-run.
For Ubuntu users: update your Certbot to 0.31.0-2 from the PPA, which has had the required fixes.
(Post has been edited to reflect that an upgrade to 0.32.0 is required, not 0.29.0 or 0.31.0).