If I may add here?
Allowing your server to be open, brokered by Plex.tv (Remote Access button), asserts a few requirements.
- PMS is essentially open to all IP addresses but further qualifies server access to those which have been validated and are allowed access as authenicated by Plex.tv
- Mobile IP addresses are by definition dynamic
- Remote IP addresses from those you share with are by definition dynamic unless they have static IP addresses assigned by their ISP
There are a few things which impact how well PMS Remote Access accessibility tests and “Async ID” work.
What I’ve found to be the single, most important, aspect is:
How well does the local modem/router UPnP actually keep a well maintained table, expiring old port mappings in favor of new ones?
As prime example of this, my ISP-provided T-3200 modem was terrible. It would always reply to PMS that the port is opened but never actually open it because the mapping table was full. It never cleared the old port-forwarding mappings to port 32400 (internal).
The interim workaround for this was to:
- Manually open an odd port number on the modem/router (e.g. port 53421) and forward it to static IP of the PMS server
- Specify 53421 as the manual port for Remote Access.
This worked most of the time. Occasionally AWS timing was slow enough that PMS didn’t get the required Reachability Test (the generator of those ASYNC-IDs) before PMS gave up waiting.
The solution, for me, was to obtain a well-behaved modem/router and replace the ISP equipment.
My solution was to purchase the Netgate PfSense unit. It took over all ISP sign-in/authentication services for normal internet access.
It is a proper stateful firewall which profoundly increased my security level.
It is a fully functioning firewall in that I can specify special cases in whatever form I need through the use of NAT/Firewall aliases and a companion “PASS” rule.
Lastly, it has a properly functioning UPNP handler.
The UPNP handling alone solved all my remote access problems.
I test a number of platforms concurrently, each of them having Remote Access. Every one works perfectly.
Thanks to pfSense, I took all firewall management out of the hosts and put it where it belonged – at the edge device.
On Synology, Make certain to have selected one adapter as the default gateway. The first adapter in the device (lowest number used) is the best to use. If you use an adapter other than the first found, Inform PMS to use that Preferred Adapter (Settings - Server - Network - Show Advanced - Preferred Interface)
Hope this helps.
