Let's Encrypt caught in the Friday night maintenance syndrome

Hello,

While I was getting ready to deploy a new service to visualize my traffic statistics, I briefly thought I had broken my NPM (Nginx Proxy Manager) configuration. Indeed, I was getting some rather vague errors and, when checking the ad hoc folder, I couldn’t see any new directory for the key and certificate I was trying to obtain.

It was only after checking the Docker container logs that I realized the problem wasn’t on my end.

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[5/8/2026] [7:27:32 PM] [SSL      ] › ℹ  info      Requesting LetsEncrypt certificates for […].marcjestin.fr
[5/8/2026] [7:27:32 PM] [SSL      ] › ℹ  info      Command: certbot […].marcjestin.fr
[5/8/2026] [7:27:33 PM] [Nginx    ] › ℹ  info      Reloading Nginx
[5/8/2026] [7:27:33 PM] [Express  ] › ⚠  warning   Saving debug log to /data/logs/letsencrypt.log
An unexpected error occurred:
The service is down for maintenance or had an internal error. Check https://letsencrypt.status.io/ for more details.
Ask for help or search for solutions at https://community.letsencrypt.org. See the logfile /data/logs/letsencrypt.log or re-run Certbot with -v for more details.

And the confirmation on https://letsencrypt.status.io/:

This is the very first time I’ve encountered this issue.

The little detail that amused me most when visiting the status page was that a scheduled maintenance had been performed on the same resources just a short time before the incident (see screenshot below).

It’s a safe bet that the two are linked.

Even though I am aware that the maintenance occurred during the morning in San Francisco, where the ISRG is based, it’s a good time to remember that:

the best time to schedule maintenance is definitely not late Friday afternoon, just before leaving for the weekend.

Best regards,

Marc JESTIN
https://marcjestin.fr