I looked at other similar topics, but couldn’t find the reason. I might have missed some info. Automatic renewal of the SSL certificate has been failing for months on one of my forums. From acme.sh.log: [Thu Sep 18 00:32:58 UTC 2025] error='"error":{"type":"urn:ietf:params:acme:error:connection","detail":"2a01:4f8:c17:6ebb::: Fetching https://forum.tevives.fr: Timeout during connect (likely firewall problem)","status": 400' [Thu Sep 18 00:32:59 UTC 2025] response='{ "type": "urn:ietf:params:acme:error:malformed", "detail": "Unable to update challenge :: authorization must be pending", "status": 400 }' Rebuilding the app properly renews the certificate. This is a standard install, no fancy stuff, no CDN, no reverse proxy, etc. The firewall is set as: [image] Any idea why this issue happens, and how to fix it?

I recently worked on the le cert renewal. It is the http to https redirect - acme does not handle being told to redirect well at all and by default attempts to connect on the same protocol (http) as it did when it was setup initially Recent updates to the let’s encrypt template should fix these renewals going forward.

EDIT: TL;DR: I don’t know. When was your last rebuild? Oh, but this has been going on for a while. There was something recently about the http port being redirected for .well-known paths, but yours it https. It doesn’t make much sense that it’d be timing out unless the acme process that’s supposed to be listening isn’t for some reason.

[image] pfaffman: When was your last rebuild? Oh, but this has been going on for a while. I rebuilt yesterday since the certificate wasn’t renewed the day before. It also failed the June 20th and I had to rebuild as well.

Let's Encrypt certificate doesn't automatically renew, but rebuilding does trigger the renewal

Product Support

pfaffman (Jay Pfaffman) September 19, 2025, 6:15pm 4

The other thing you can do next time is try running it by hand in the container to see if you can get some other idea then.

Topic		Replies	Views
Let's Encrypt certificate did not automatically renew Product Support	14	2389	October 5, 2021
Discourse failure to renew certificate Bug letsencrypt	24	1346	December 23, 2025
Let's Encrypt SSL certificate not renewing automatically 2nd time consecutively Product Support letsencrypt	3	430	January 26, 2026
Unable to renew Let's encrypt certificate Self-hosting letsencrypt	7	1182	February 7, 2024
SSL LetsEncrypt renewal not working (due to an extra reverse proxy on the outside) Self-hosting	8	1266	September 16, 2020

Let's Encrypt certificate doesn't automatically renew, but rebuilding does trigger the renewal

Related topics