Login loop when trying to login

[tomg404]

Steps to reproduce

1. Try to login via my domain https://xxx.synology.me/owncloud
2. Try to login via local ip https://192.168.188.57/owncloud

Expected behaviour

Both methods of login work fine.

Actual behaviour

I can only login via the local ip address. When I try to login via my domain nothing happens and I get redirected back to the same site. The only difference is the URL:
https://xxx.synology.me/owncloud/index.php/login?user=abc&redirect_url=%252Fowncloud%252Findex.php%252Fapps%252Ffiles%252F

Server configuration

Operating system: Synology DSM 6.2.3-25426 Update 3

Web server: nginx

Database: MariaDB 10

PHP version: 7.3

ownCloud version: 10.6.0

Updated from an older ownCloud or fresh install: Fresh install

Where did you install ownCloud from: https://owncloud.com/download-server/

Signing status (ownCloud 9.0 and above):

https://192.168.188.57/owncloud/index.php/settings/integrity/failed
No errors have been found.

The content of config/config.php:

https://pastebin.com/zHDHSd5U

List of activated apps:
It’s a fresh installation so I didn’t activate any apps by myself.

Are you using encryption: no

Are you using an external user-backend, if yes which one: no

Client configuration

Browser: Firefox

Operating system: Windows 10

Logs

ownCloud log (data/owncloud.log)

https://pastebin.com/uBFCR2M6

[tom42]

Hey,

i have seen the following in your config report:

"server SAPI": "fpm-fcgi",

From what i have read in the past ownCloud only supports mod_php so the different unsupported module could be the reason for this problem.

Unfortunately i can’t provide a solution (i don’t have much knowledge on ownCloud) besides trying to use mod_php instead.