sometimes during setups the env variable is not applied for some reason. you can manually enter the supported domains to config/config.php. maybe that's the cause

Hi u/nxtmalteser, can you follow https://github.com/nextcloud/all-in-one/blob/main/reverse-proxy.md#6-how-to-debug-things?

Short and easy answer is switch to ”Caddy” search for caddy reverse proxy. Best thing i have ever used in terms of proxy 😁

IMO Nextcloud AIO is a mess that doesn't work properly for anyone used to docker and docker networking. It makes lots of bad assumptions about how things are configured.

Managed to gain access to the container by using the docker virtual ip of the apache container, but i see this as no solution because the virtual ip can change whenever an update is applied.

The reverse proxy docs have something in the section "Running the Reverse Proxy in a Docker container on the same server"

It sounds like they want you to use network mode host on the NGP container which is dumb, but should work in theory. Then you can use localhost in NGP.