Plex over Tailscale

I’m new to Tailscale, it looks great. I have it installed on my Mac and a couple of Raspberry Pis. From my Mac I can ping the Pis, eg:

$ tailscale ping 100.124.75.114
pong from rpi4 (100.124.75.114) via 192.168.1.22:41641 in 5ms

I can also ssh etc, everything seems fine - using either the Tailscale hostname or the Tailscale IP. This works whether I am on the same local wifi network, or if I use my phone’s hotspot (ie through my mobile provider, not local network). Excellent.

However I run Plex on one of the Pis, and I can’t access the web UI over Tailscale. On the same local network as the Pi, if I visit 192.168.1.22:32400 (the Pis local/internal IP) I can browse the Plex UI and see my library etc. But that does not work if I use the Tailscale IP, nor the Tailscale hostname. http://100.124.75.114:32400 shows a Plex page with the msg “Something went wrong”, and my library, settings etc are not accessible.

Similarly if I use my phone’s hotspot and try from outside my local network - “Something went wrong”.

Should this just work, or is there something else to configure? Have I missed something?

Thanks.

Hi
Based on what you are saying:
" But that does not work if I use the Tailscale IP, nor the Tailscale hostname. http://100.124.75.114:32400 shows a Plex page with the msg “Something went wrong”, and my library, settings etc are not accessible."

Do you think it’s something to do with the plex config as you said that a plex page is showing? Does it need to be https instead of http:? Just a thought, sorry i’ve all very new to all this…

I seem to have stumbled on the solution. Writing it up here in case it helps anyone.

Watching the Plex logs I noticed errors like:

Mar 27, 2022 10:54:15.536 [0xb24b1d48] WARN - [HttpClient] HTTP error requesting GET https://plex.tv/media/providers?X-Plex-Token=xxxxxxxxxxxxxxxxxxxx (6, Couldn't resolve host name) (Could not resolve host: plex.tv)

and

Mar 27, 2022 10:35:10.666 [0xb2149d48] ERROR - HTTP -6 downloading url https://plex.tv/updater/products/5/check.xml?build=linux-armv7neon&channel=16&distribution=debian&version=1.25.6.5577-c8bd13540
Mar 27, 2022 10:35:10.666 [0xb2149d48] INFO - AutoUpdate: error getting data from plex.tv

So, looks like DNS problems, maybe ipv6 related (those 6s looks suspicious to me).

I checked the Pi’s /etc/resolv.conf and found it had an ipv6 address for nameserver. I don’t know why, nor where it came from, nor what that address maps too, as I have ipv6 disabled on the Pi and my router doesn’t have ipv6 enabled.

/etc/resolv.conf is auto-generated (from settings in /etc/dhcpcd.conf apparently), so I rebooted (twice) to make sure that setting was current and persistent, and it was.

I found the relevant setting in /etc/dhcpcd.conf was blank:

static domain_name_servers=

I modified it to Google’s DNS servers:

static domain_name_servers=8.8.8.8 8.8.4.4

and rebooted. Now /etc/resolv.conf seems to have been generated by Tailscale!

# Generated by resolvconf
search [my-tailscale-login-email].beta.tailscale.net
nameserver 100.100.100.100

Which I didn’t expect, but my guess is this is how MagicDNS works (I do have that enabled), so I guess makes sense. I confirmed /etc/resolv.conf looks the same on another of my rpis with Tailscale, though not on my Mac which just lists my router IP as the nameserver.

And now Plex works as expected! Locally and remotely, both with the Tailscale IP and the Tailscale hostname.

If anyone has any insight into how that ipv6 address got into /etc/resolv.conf I’d be interested to hear.

Thanks.