I have been using Plex with remote sucessfully for several years. I resently had to replace a HDD in my Synology DS-920+ (RAID 5 configuration). The new HDD has completed being added. In the process, however, Plex began failing remote access. It acts like a double NAT failure, but I don’t know how changing an HDD in my NAS would cause this.
My modem is a HUNAX BGW320-500 and is configured as Passthrough with NAT disabled and port forwarding for 32400 to 32400 TCP/UDP. I have a Deco mesh network with port forwarding also for 32400 to 32400 TCP/UDP. This has been working for years…until I changed a HDD.
If your NAS device is getting an internal IP address dynamically assigned by your router (instead of having a fixed IP reserved), it could have changed its IP address after the shutdown for replacing the hard drive.
Verify that your port forwardings are still pointing to the current IP of your NAS.
The NAS DHCP IP assignment is reserved and port forwarding remains pointed to that IP.
If I move off the RA page or refresh the page, RA drops out. Manually re-applying the port assignment, it returns and holds as long as I remain on the RA page. So, it appears UPnP may not be working, yet the router has UPnP set on.
Problem found, I think. Just before I changed the HDD, I was having some network problems. In the process of troubleshooting the network problem, I swapped the mesh main router (Deco M9+) with another M9+ on the network. I didn’t think this would have any impact on Plex as long as the network and Internet access remained good. In retracing all my steps, I found what appears to be the problem. The modem/router is a HUMAX BGW320-500 and it is set to the passthrough mode. In that setting, a dropdown let’s you select the router it is passing to. The problem is, all the mesh routers are named the same but have different MAC addresses. The router selected there was still the old router MAC. I manually enter the MAC address of the new main router and that seems to satisfy Plexserver as remote access is now holding.
