Plex remote works *sometimes* and I can't figure out why

Plex Media Server Remote Access
1

Server Version#: 1.43.0.10231
Player Version#: Multiple

I am having a weird issue with remote users directly connecting. Some preliminary info:

  • I am running the server on bare metal Linux
  • I have a specific port forwarded from my router to the server IP (was using 19299 but I’ve tried a few others)
  • I am absolutely, positively, 100% NOT behind CGNAT
  • My ISP’s router is in layer 2/bridge mode. It does not have an IP address, and my external IP (as shown by sites like whatismyip.com) matches the WAN IP of my personal router
  • I have a lifetime Plex Pass

So yesterday, my daughter (an external user) mentioned that Plex wasn’t working for her. Specifically, she’d try to start watching something, but it would just spin.

I checked my dashboard and saw three users watching streams, but oddly all three were going via relay. At least one of the users is one that I frequently see go direct (he’s a friend and we’ve debugged his specific connection before to get him going direct).

I checked the Remote Access page on the web interface. It showed that remote access wasn’t working. I clicked retry, and it changed to Fully accessible. I pulled my phone out, disabled WiFi, and tried to play something. It went via relay. I disabled relay and tried again, and now it said my server was unavailable.

I re-enabled relay, and tried once more. Same thing. So now I tried Plexamp. That worked, and it played direct! So I pulled my phone back out (still with wifi disabled) and tried to play the exact same video I tried before, and now it played direct.

In terms of port debugging, as I said earlier, I started with 19299 (which I’ve been using since I first set my server up many years ago). I went to canyouseeme.org and checked to see if it saw the port open. It did not, despite the fact that it is open on my router. I went to GRC.COM and used Gibson’s ShieldsUp! port tester, and that said the port was open.

I manually tried a couple of different ports in the 20000-30000 range, with the same results. I enabled UPnP on my router and set Plex to find its own port, which it did. This did not change my playback experience, but now canyouseeme.org and grc.com agreed that the port selected was open. But again, I wasn’t able to successfully play direct until after I tried Plexamp.

Sometimes on the webUI, remote access shows green. Sometimes it shows red, but when I go to the actual page, it refreshes to green. It’s driving me crazy.

Any ideas or suggestions?

2

If you have created a manual port forwarding in your router, did you tell Plex that you did so?
i.e. by ticking the check box “Manually specify public port” and putting in the external/WAN port number into the field behind it.
Notice that the internal/LAN port number must always be 32400. Only forward TCP packets (i.e. not TCP and UDP both)

Port forwardings which were created by UPnP will work after a server restart (or clicking on “Retry”) are nowadays disabled after some hours.
Your issues might very well be caused by this alone.

A second thing is over-zealous power saving settings.
Disable EEE (energy-efficient ethernet) in the settings of your server ethernet adapter and/or your ethernet switch.
Do not allow the ethernet adapter to slow down the link speed when it’s idle. (same location for this setting)
Do not connect your Plex server wirelessly (likelwise the NAS/file server with your media files, if applicable).

3

If you have created a manual port forwarding in your router, did you tell Plex that you did so?
i.e. by ticking the check box “Manually specify public port” and putting in the external/WAN port number into the field behind it.

Yep.

Port forwardings which were created by UPnP will work after a server restart (or clicking on “Retry”) are nowadays disabled after some hours.
Your issues might very well be caused by this alone.

Except it started when I had a manual port set.

A second thing is over-zealous power saving settings.

All energy saving options are disabled, and the server is hard wired (same with the NAS holding the videos).

4

This version is a Beta release with the new ffmpeg 6.1
You might want to roll back to 1.42.2.10156 to see if it resolves the issue.

5

So I rolled back to 1.42.2.10156. No change. Right now, here’s what I’m observing

When not set to manual port, it now showed as Not available outside your network. So I picked a new port (28799), set it manually, and set the port as open/forwarded in my router.

I did that and clicked Retry, and it showed as fully available. Sat on the page for a while; no change. Clicked on Dashboard, then back to Remote Access, and it turned red/not available. Both canyouseeme.org and grc.com show the port open.

6

Did you go thru the Remote Access Troubleshooting guide?
If you disabled UPnP on your router when you set it up for manual port forwarding, you’ll need to re-enable UPnP when you turn off manual port.

7

If canyouseeme.org reports the port is open, then there is no need to try changing ports, using UPnP, etc.

You can also test by placing your phone on the mobile network (no wi-fi), then pointing its browser at the IP address and port of your server. For example, https://1.2.3.4:28799/web (use the real public IP address and port). It should pull the Plex Web login page from your server.

When enabling remote access, PMS “optimistically” says the server is available. In reality, it is still trying to register the server with plex.tv. If the process fails, then the remote access page changes back to “Not available…” The process can take anywhere from 30 seconds to two or three minutes.

Some things to try:

  1. If not needed, disable IPv6 on the server.

  2. Configure the Plex server to use a public DNS server such as 1.1.1.1 (Cloudflare), 8.8.8.8 (Google), or 9.9.9.9 (Quad9).

  3. Then either (a) reboot the server or (b) stop Plex, flush the DNS cache, start Plex.

8

Can this be the result of Cloudflare outages? I can connect via my WAN IP that Plex Remote Access settings give me, but I can’t login via https://app.plex.tv/desktop. Or, I CAN log in, but “No content available”. I do not use Cloudflare myself, but maybe Plex servers do?

9

I am running on Linux and experiencing the same issue. Went through the troubleshooting guides and nothing works.