cURL error 6 on all my feeds... but they work if I delete and recreate them??? 🤔

[Julianoe]

Some context on my install:

Nextcloud: 33.0.4.1
PHP: 8.4.21
Database: MariaDB 11.4.11
Deployment: Docker container behind Apache reverse proxy, hosted at a dedicated server host
OS: Linux server (Docker host)
Nextcloud News app installed
Cron jobs: running correctly
Internet connectivity check: OK from Nextcloud admin panel

Issue

Nextcloud reports that some all the News feeds stopped updating due to cURL error 6: Could not resolve host:
The issue is specifically affecting RSS feed updates in Nextcloud News, while the rest of Nextcloud remains functional.
Every single one is failing to update.

When I delete a feed and add it again, it works. I don't understand.
I've read every thread about News failing to a related cURL error and noone seem to have the same issue. I'm not behind a pihole and disabled temporarily some firewalls and fail2ban etc during testing. It was working properly before that. 3 weeks ago I updated and now it's broken.

[Julianoe]

As recreating a feed seemed to work I tried to refresh one from the command line with docker exec -u www-data nextcloud-app php occ news:updater:update-feed username 619
It worked.

I then refreshed all the feeds with docker exec -u www-data nextcloud-app php occ news:updater:update-user username
I don't have errors anymore and my desktop and mobile clients synced properly too.

I still don't understand why it failed though

[Grotax]

Maybe related to this: #3599

Maybe you have temporary DNS resolved issues.

In the linked issue you can find information what tools can help to check.