Losing and regaining remote access without double NAT

Plex Media Server
1

Hi, I have been puzzled by this for a few days trying to fix this.
The server runs on a windows system with a preferred IPV4 address. (192.168.0.244)

I use an ISP provided modem/router on which I turned off the radio/wifi signal.
An ethernet cable goes from ISP modem/router to TP-Link Deco m9 which is set in to “Access Point” mode. With ipv4 address 192.168.0.110. It supplies the wifi for other devices and cabled internet access to the PMS on Windows.

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I have entered the 32400 port inside the " ** IPv4 Firewall & Port forwarding** options on the ISP provided moden/router. As follows:

Local IP Address - starting port (ext) - end port (ext)-Starting Port (int)-Endport(int)-Protocol-Status
192.168.0.244 - 32400 - 32400 - 32400 - 32400 - TCP - enabled

UPNP is enabled
DMZ address is 192.168.0.0 (default)

And yet everytime I go to the remote access menu in the PMS settings I get a red exclamation mark. When I click retry it shows all good. Until I wait it goes back to “Not available outside your network”
Until I click “Retry” again. And then it goes back to " Fully accessible outside your network " -_-’

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Network settings in PMS:
Enabled: Treat WAN IP As LAN Bandwidth

Any recommendations?
Do I have to forward the ipv4 adres of the Deco router as well inside the ISP provided modem/router settings?
Because in that interface of the ISP modem/router I can only change the last group of digits. Like so:

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I did test playing something throught the plex app on android, when playing started it did not give me a message about not being connected directly and just played the content.

But when I play something through the Plex Media Player on the system where PMS is running it shows “Remote”, is that normal? EDIT: This was because I entered “255.255.255.0” inside the “LAN Networks” field, emptying the field seemed to have fixed that, it now shows “Local”. If someone could explain this? Since “IP/netmask entries” are allowed, maybe I don’t understood it correctly.

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While in the firewall rule settings I have plenty more options:

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Only I do not know completely how to fill in those fields with the information I have.

Any help would be a appreciated

Server Version#: Version 4.54.5
Player Version#: Version 4.29.2

2
  • If you create a manual portforwarding, you don’t need to activate UPnP.
  • If you create a manual portforwarding, you need to tell Plex that you did so, by ticking this checkbox and putting the external port number (32400 in your case) into the input field:
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  • If your second router is in AP mode, you don’t need to create port forwardings in its settings.

Did Plex warn you about Double NAT?
If this warning appears, even though you did everything to avoid it, it might be caused by CGNAT. Carrier-grade NAT - Wikipedia
Which unfortunately cannot be solved without the help and cooperation of your ISP.

3

Thank you for the advice, I appreciate it.
I think I changed to many things after each other withouth keeping up. But what I did was creating a port forwarding rule with the standard port. It did not trigger the idea that I should have ticked the “manually specify public port option”. Because it was the default port number.

I have disabled UPnP and checkled the “manually specify public port option” box.
It seemed to have fixed it, the status is stable now.

With my setup do I have to create a portwarding rule?

Will disabling UPnP cause issues with other (smart) devices?

Did Plex warn you about Double NAT?
If this warning appears, even though you did everything to avoid it, it might be caused by CGNAT. Carrier-grade NAT - Wikipedia
Which unfortunately cannot be solved without the help and cooperation of your ISP.

No it did not warn me, it did give me the warning when my Deco wireless router was in “Router” mode. But I changed it because of this warning, after finding out it was in this mode by default because I was having connection issues with other devices caused by having more than one device serving out IP addresses.

I read the documentation regarding troubleshooting remote access https://support.plex.tv/articles/200931138-troubleshooting-remote-access/
And compared the two ip adresses, they where the same.

  • If your second router is in AP mode, you don’t need to create port forwardings in its settings.

I cannot enter any port forwardings in the Deco when it is in Router mode.

4

Not necessarily, but I strongly recommend it.
Automatically created port forwardings are volatile on many routers and get destroyed after a certain time. Usually after 12 – 24 hours.

Possibly, if these devices use portforwardings themselves.
(e.g. a game console when you join an online gaming session)

If you own such devices, you might want to keep UPnP activated. But you don’t need to activate it solely for Plex.

This was in response to your question:

Do I have to forward the ipv4 adres of the Deco router as well inside the ISP provided modem/router settings?

5

Please - and make it something other than 32400
…since you’re right there anyway…

6

Alright, thank you @OttoKerner for all the help. I am going to enable UPnP for the other devices.
I thought I had to portward all the devices (in the network, modem/router → deco → pms)before the system that runs the PMS.
@JuiceWSA might as well, just a bit hesitant to touch it now, it works.

7

I changed it to something else “51221” I have the same problem now, it switches between unavailable and available.

8

You will have to put this new port number into the above mentioned input field in Plex as well.
Then Save and restart your server and let it sit for a few hours. Don’t expect it to be stable instantly. There are simply too many components which need to be updated in unison here, to show an immediate success.

9

Alright, I will try this as soon as I get to the system to restart PMS after the portforwarding change.
Edit: So the order order is, change port number in ISP modem/router interface, change it in Plex settings, reboot PMS, wait?

10

I set mine to be within this range:

20,000 to 50,000

In order to forward a port for Plex Media Server, you’ll need three main pieces of information: WAN/External Port : Port 32400 (TCP) is default, but you can generally use any available port in the 20,000 to 50,000 range .

It was actually Otto that suggested that - many moons ago - and I have no idea if it’s still valid.

It was at that time I also reserved a local DHCP address - so that would never change and be difficult.

11

This recommendation still stands. Though nothing keeps you from using any other port number. But if you use any of the well-known ports, you better know what you’re doing.

12

That’s new (the well known ports).
The one I selected those moons ago isn’t one of them.

13

Nothing changed with waiting, I am going to go back to 32400
I dont know what is wrong with port 51221.
Edit: I am so stupid, I should have read, the post from @JuiceWSA before replying of frustration.
I will change it to something between 20,000 to 50,000, when nobody is using the PMS. Thanks

14

Alright changed it to this morning to 32004. restarted PMS. And waited for 3 hours. The same problem is back, " Not available outside your network" until I press “Retry” the status will show “Fully accessible outside your network”
I am going to change it back to the default port.

15

Just so we’re clear: you are always changing

  • only the external port number in the portforwarding setting in your router (and not also the internal port number – this one must always remain at 32400)
  • at the same time, the external port number value in the Plex interface
16

I change everything when changing the port number in the router.

  • only the external port number in the portforwarding setting in your router (and not also the internal port number)

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And then I change it in plex, save it and restart PMS.

17

That is the mistake you are making.
Plex server will always use 32400. It is in the router where you are changing the number.
You must only change the (external) input fields in the above screenshot.

1 Like
18

Alright! thank you!
So it looks like this:

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And in PMS:

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19

Correct.

20

Thank you, legend. :pray:
Have a nice day

1 Like