Something is already listening on port 80 on the pi, which is why your tunnel failed.
Been a while since I set up OMV myself, but does it even use port 80? Doesn't it expose its web UI on a non-standard port?
Something is already listening on port 80 on the pi, which is why your tunnel failed.
Been a while since I set up OMV myself, but does it even use port 80? Doesn't it expose its web UI on a non-standard port?
The issue was much more straightforward than i thought. It seems sometimes thinking of too complex issues will hinder finding the easiest cause - the local forewall on the pi was blocking it / had no explcite allow.
To check i did: sudo ufw status verbose
There was only port 22
I added the new port as Allow Port 8081: sudo ufw allow 8081
And it works now!