Nextcloud: fixing "maintenance mode is enabled"

What the message looks like

Nextcloud is in maintenance mode, no apps are loaded.

Common causes

• The web updater or a package update was aborted and occ upgrade never completed.
• A backup script enabled maintenance mode and failed before turning it off.
• 'maintenance' => true is still set in config/config.php.
• Wrong file ownership after the update, so occ cannot write config.php.

Check

1. Show status and versions
   sudo -u www-data php /var/www/nextcloud/occ statusCopy
2. Check maintenance in the config
   grep -n maintenance /var/www/nextcloud/config/config.phpCopy
3. Latest errors in the Nextcloud log
   tail -n 20 /var/www/nextcloud/data/nextcloud.logCopy
4. Is the web updater stuck?
   ls -la /var/www/nextcloud/data/updater-*/Copy

Fix

• Finish the pending upgrade: sudo -u www-data php occ upgrade.
• Then turn it off: sudo -u www-data php occ maintenance:mode --off.
• Stuck web updater: remove the .step file in data/updater-*/ and rerun the update with php updater/updater.phar.
• Fix ownership: chown -R www-data:www-data /var/www/nextcloud.
• Use trap in backup scripts so maintenance mode is switched off even on failure.

FAQ

Can I just set maintenance to false in config.php?

Yes, but only if no upgrade is pending. Otherwise Nextcloud shows the update page or errors afterwards. Check occ status first.

How is this different from maintenance:singleuser?

Single-user mode still lets admins in through the browser; regular maintenance mode locks out everyone.