I'm a bit hesitant to activate the tag in the DSM, as it states that it then needs a tagged counterpart to be reachable, and since all the other devices in this subnet aren't tagged anymore (as the switch untags the vlan at the port)
Connect a laptop into the same subnet as your Nas (so same vlan and IP range/subnet) and connect to the nas. This either eliminates the NAS or the router from the equation
did that, the NAS is easily reachable from within the subnet it's only a problem from another subnet
okay that's what I thought
if I try to ping it it doesn't answer, the unifi logs do show that the packages have been forwarded to the subnet. If I use netcat to open a port on the other device it receives the connection request, but the NAS doesn't recognize it. Maybe I have to do some Wiresharking on a mirror port to see what exactly comes back, hoped I could get around it