Remote Access Works in Apps But Not in Browser (app.plex.tv)

[Thearniec]

Server Version#: 1.41.4.9463 (says up to date)
Player Version#: 4.143.0
Router: Asus GT-AXE 11000 Firmware [3.0.0.4.388_23870]

I set up a new Plex Server last week. It is on a Mac (OS Squoia 15.3.1 (24D70)). Everything was working fine. I could access my library through apps on iOS, Apple TV, and the web browser https://app.plex.tv/desktop.

Yesterday morning I went and played a movie using the web browser. The movie was 1080p and on my network but the playback stuttered, then froze.

Since then I cannot connect to my Plex server at all through app.plex.tv. I’ve tried on both Chrome and Safari

My server works fine on the iOS apps (both iPad and iPhone, both on my WiFi and remotely). But app.plex.tv it says my server has been offline for 19 hours.

On my server under Remote Access it says “Fully Accessible Outside Your Network.” (Occasionally this flips to Not Available Outside Your Network but if I page refresh it shows Fully Accessible again).

I’ve gone through all the troubleshooting steps listed at https://support.plex.tv/articles/200931138-troubleshooting-remote-access/?utm_source=Plex%20Forums&utm_medium=Sidebar&utm_campaign=Plex%20Forums

Here are the results of that troubleshooting:

I have validated the server and my session in app.plex.tv are both signed into the same account. My server shows in app.plex.tv in the list of “Authorized Devices” but offline for 19 hours.

I checked my router configuration UPnP is enabled. (It was before and after the issue). I turned it off and then back on. No help in either state.

I switched my Mac from having a dynamic IP to a static IP. I then set up port forwarding on my router, external port 32400 to go to the new static IP internal port 32400. I told Plex Server to use port 32400. It didn’t make a difference. I then turned port forwarding back off (since it wasn’t enabled when the service was working 2 days ago).

My router does have a firewall enabled. I turned it off just to make sure it wasn’t causing a problem, and it made no difference. I then turned it back on.

I have a static IP from my ISP (NextLink). I have validated that my router’s IP is also my external IP so I am not double-NAT-ed.

I checked my MTU is set on my Mac to 1500. My router does not support a custom MTU.

I have set Secure Connections to both Required and Preferred and it made no difference.

I validated that at https://app.plex.tv/desktop/#!/settings/devices/pms I only have the one server listed. The old server (now offline) is not there.

I rebooted the Mac server.

I tried accessing the server directly from https://192.168.x.x:32400 and that did work. So it’s something specific to the plex app website.

I really appreciate any help someone can offer!

[pshanew]

Visit this page in a web browser (if using Safari, you’ll need to have developer options enabled in order to view the page):

https://plex.tv/api/resources?includeIPv6=1&includeHttps=1&X-Plex-Token=[your_plex_token]

You can find your Plex token using the information here:
https://support.plex.tv/articles/204059436-finding-an-authentication-token-x-plex-token/

Once you’ve loaded the resources page, find your server and look at its published connections. Make sure they look correct. That is, the one marked local=“0” should reflect your public IP and the port should match that shown in the remote access section of PMS’ settings.

Also, do you see the same behavior with the Plex desktop app?
https://www.plex.tv/media-server-downloads/?cat=plex+desktop&plat=macos#plex-app

It would likely provide a better experience than a browser anyway. But regardless it would be good to test with just to see if the problem is specific to the web client.

Regarding port forwarding vs. UPnP, I would generally prefer the former. UPnP, if poorly implemented, can expose its own security risks. And the end result of both is the same: a port forward is created. The difference being that with a static port forward, you are in control of its configuration.

Finally, regardless of which method you land on, use port checker such as canyouseeme.org to ensure that the port is indeed open.

[Thearniec]

Thank you so much for the detailed reply.

The server shown does have my public IP. The port shown matches what is in the Plex configuration. I then manually went and put that port forwarding on my router too to try that. Still no dice.

The desktop application works just fine, just not the plex browser experience.

I turned off UPnP and set up the manual port forward. canyouseeme.org says the IP and port are both accessible (and it still is working through the desktop app and other apps) but not the browser.

With the desktop application getting the browser to work isn’t paramount for me, but I’m still wondering if it indicates there’s something more wrong in my setup so I’d like to fix it if possible.

Thanks again for the help!

[Thearniec]

Got it fixed! I’m not sure why this would be the culprit but I changed my Router’s DNS server. It had been set to my ISP’s DNS server. I switched it to Google (8.8.8.8) and it instantly got it working.

Thanks again for the help!

[pshanew]

@Thearniec

Thanks again for the help!

You’re welcome, glad you got it working.

What you describe sounds like a DNS rebinding protection issue, but that shouldn’t affect remote connections. But, as the old network engineers’ saying goes, it’s always DNS.

For what it’s worth, I’d stick with the desktop app over the browser, when possible. You’ll generally have a better experience (fewer opportunities to transcode).