Connection Timeout when uploadin larger files


I’m new here and started just shortly with NextCloud.

I have setup the latest stable version of NextCloud via docker and set up an external nginx.

Both containers are connected via ProxyPass. Everything is running smoth.

I’ve started to use the auto backup functionality to upload my images and videos I took on my smartphone. On huge files like videos I ca see that the upload was successful (100%) but then the upload fails with a timeout message. It seems that the nginx cancels the proxy connection as the NextCloud container takes too long to finish the upload.
The logfiles do not show something specific.

I was able to find such a behaviour with suggestions on how to fix it when using the fpm+nginx (integration via fastcgi) but not for ProxyPass integration.

Any idea which parameters I can set to prevent the timeout?