First, a quick clarification: while you may have searched for "harp," the correct term is , which stands for Nextcloud AppAPI HaProxy Reverse Proxy . It represents a significant leap forward in how Nextcloud interacts with external applications.

To achieve this, you will need to use the approach. You would manually start the ExApp container on your remote GPU server, ensuring it's configured to connect back to your central HaRP container. Then, you register this pre-existing app with Nextcloud via the occ command, using the manual_install daemon type. This tells Nextcloud that the app is already running elsewhere and not to try to deploy a local copy.

HaRP sits behind your main reverse proxy and acts as a dedicated bridge for communication between the Nextcloud server, the client UI, and ExApps.

When two nodes (e.g., a laptop and a Nextcloud server) reconnect after offline periods: