Plex server becomes unreachable after large files transfers, until Plex server is restarted

Plex Media Server
1

Server Version#: 1.22.1.4200 currently, but has been happening for a few months/versions of Plex
Player Version#: N/A
OS: Windows Server 2016

I’ll try to keep this brief, but I have a fairly complex home lab/Plex setup.

Machine A hosts my Plex Server, various *arr applications, and the storage drives used to store my media.
Machine B is used to convert/optimize media via Handbrake with a low power GT 710 GPU.

Network consists of a basic consumer TP-Link Archer C8 router, and a HPE 1920S 24 Port switch. Machine A (Plex Host) is connected to the switch via dual gigabit NICs and Machine B is only using a single gigabit NIC, connected to the switch.

When I’m transferring files from Machine B to Machine A, Machine B will use all of it’s available gigabit network traffic and the load is balanced evenly between the dual gigabit NICs on Machine A. This should leave a full gigabit available between the two NICs, or 500 megabits for the NIC I have dedicated to Plex. All NICs in question have their own IPs and there’s nothing fancy configured like LAG or anything.

However, after a minute or so of file transfers, my Plex server becomes unreachable, while the host is still fully functional along with all of my other services/applications/devices on the network. Even after the file transfer has finished, or if I pause it, the Plex server does not become reachable until I restart the service. I do have Plex running as a service via NSSM. The service does not crash or restart either.

I don’t currently have logs to post as it’s been a few days since this last happened, and I don’t want to force it to happen again yet. However, I can replicate this and post logs if necessary.

2

Plex really doesn’t like multiple IPs on the same subnet. It’d be much happier with LAG or some sort of round-robin if your switch doesn’t support LAG (I don’t know HP). Once you get into the logs you can watch it flip/flop like crazy across the IP addresses - likely this is killing it.

4

I should have mentioned that I originally was only using 1 NIC due to possible failures (ended up being unrelated), but connected the second as a test. Same results though.

I was also using NIC Teaming via Windows (not hardware/drivers) and ran into the same issue.

5

So if it did the same when bog standard logs are going to be required.

you can try taking it out of NSSM to see if it changes behaviour.

plex mostly assumes its running on a nice basic “mommy and daddy” desktop, adding layers of complexity mostly always trip it up in some way.

6

I will try both of these tomorrow and also do so with the second NIC disconnect, just to rule that out as well.

Yes, definitely lol. I’ve ran into a lot of weird issues where I know it’d work in an enterprise environment, but Plex just does not agree.

7

I think they get a bit stuck between not wanting it to be easily out-of-the-box enterprise ready as they cover that with different licensing and trying to make us advanced home users/tech tragics happy.

8

Of course, trying to replicate the issue and now it’s not happening… I will post logs as soon as I can get the issue to occur again.

9

Alright, finally got it to error out. The exact error says “Content Not Available” and I’m unable to reach the server settings page.

However, once I restart the service, Plex comes back online.

Complete Log Folder from after the restart. I had to use Google Drive. Errored out when uploading. I assume the archive is too large.

10

Finally had some time to actually look though my logs and I found this.

image
image1526×143 17.3 KB

192.168.1.150 is the IP of the second NIC - 192.168.1.120 is the IP of the original NIC and is what Plex is supposed to be running on.

However, while just using the NIC on .120 my local playback sessions error out with a transcoder error. Remote playback sessions seem to continue playing without error though.

11

have you set the Plex IP address in Plex?

12

yep, this is the flip/flop I referred to in my first post.

You can see it finding both nics with .120 set as primary.

Mar 25, 2021 10:20:33.907 [4844] DEBUG - Detected primary interface: 192.168.1.120
Mar 25, 2021 10:20:33.907 [4844] DEBUG - Network interfaces:
Mar 25, 2021 10:20:33.907 [4844] DEBUG - * 2 Ethernet {418A9389-BA8F-42F0-AE03-C826D83E1C63} (192.168.1.150) (loopback: 0)
Mar 25, 2021 10:20:33.907 [4844] DEBUG - * 4 Ethernet 2 {91A6017A-27B9-4628-A312-21BDEC1D3308} (192.168.1.120) (loopback: 0)

here is where is starts to flip/flop

Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Got notification of changed network (first change: 1)
Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Quick dispatch of network change.
Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Creating new service.
Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Got notification of changed network (first change: 1)
Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Quick dispatch of network change.
Mar 25, 2021 10:20:33.908 [9448] DEBUG - Network change for advertiser.
Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Creating new service.
Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Got notification of changed network (first change: 1)
Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Quick dispatch of network change.
Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Creating new service.
Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Got notification of changed network (first change: 1)
Mar 25, 2021 10:20:33.908 [9448] DEBUG - NetworkService: Setting up multicast listener on 0.0.0.0:32414
Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Quick dispatch of network change.
Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Creating new service.
Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Got notification of changed network (first change: 1)
Mar 25, 2021 10:20:33.908 [4844] DEBUG - NetworkService: Quick dispatch of network change.
Mar 25, 2021 10:20:33.909 [4844] DEBUG - NetworkService: Creating new service.
Mar 25, 2021 10:20:33.909 [4844] DEBUG - NetworkService: Got notification of changed network (first change: 1)
Mar 25, 2021 10:20:33.909 [4844] DEBUG - NetworkService: Quick dispatch of network change.
Mar 25, 2021 10:20:33.909 [9448] DEBUG - Network change for advertiser.

here is where it starts to setup local discover on both nics

Mar 25, 2021 10:20:33.909 [9448] DEBUG - NetworkService: Setting up multicast listener on 0.0.0.0:32410
Mar 25, 2021 10:20:33.910 [9448] DEBUG - Network change for advertiser.
Mar 25, 2021 10:20:33.910 [9448] DEBUG - NetworkService: Setting up multicast listener on 0.0.0.0:32412
Mar 25, 2021 10:20:33.910 [9448] DEBUG - NetworkService: Network change for browser (polled=0), closing 0 browse sockets.
Mar 25, 2021 10:20:33.910 [9448] DEBUG - NetworkService: Setting up multicast listener on 0.0.0.0:32413
Mar 25, 2021 10:20:33.910 [9448] DEBUG - NetworkService: Browsing on interface 192.168.1.150 on broadcast address 192.168.1.255 (index: 0)
Mar 25, 2021 10:20:33.910 [9448] DEBUG - NetworkService: Browsing on interface 192.168.1.120 on broadcast address 192.168.1.255 (index: 1)
Mar 25, 2021 10:20:33.910 [9448] DEBUG - NetworkService: Network change for browser (polled=1), closing 0 browse sockets.
Mar 25, 2021 10:20:33.911 [9448] DEBUG - NetworkService: Browsing on interface 192.168.1.150 on broadcast address 192.168.1.255 (index: 0)
Mar 25, 2021 10:20:33.911 [9448] DEBUG - NetworkService: Browsing on interface 192.168.1.120 on broadcast address 192.168.1.255 (index: 1)
Mar 25, 2021 10:20:33.911 [9448] DEBUG - NetworkService: Network change for browser (polled=0), closing 0 browse sockets.
Mar 25, 2021 10:20:33.911 [9448] DEBUG - NetworkService: Setting up multicast listener on 0.0.0.0:1901
Mar 25, 2021 10:20:33.911 [9448] DEBUG - NetworkService: Browsing on interface 192.168.1.150 on broadcast address 239.255.255.250 (index: 0)
Mar 25, 2021 10:20:33.911 [9448] DEBUG - NetworkService: Browsing on interface 192.168.1.120 on broadcast address 239.255.255.250 (index: 1)

here is where it decides there is a server on .150

Mar 25, 2021 10:20:38.909 [9448] DEBUG - NetworkServiceBrowser: SERVER arrived: 192.168.1.150 (SuPlex 2.1)

and starts up plexrelay (I assume as your NAT is still aimed at .120)

Mar 25, 2021 10:20:39.163 [10204] DEBUG - [PlexRelay] Authenticated to 45.79.129.106 ([45.79.129.106]:443).
Mar 25, 2021 10:20:39.212 [10204] DEBUG - [PlexRelay] Authenticated to 162.216.19.157 ([162.216.19.157]:443).

jumps back to doing local client discover from .120

25, 2021 10:20:43.910 [9448] DEBUG - NetworkServiceBrowser: Parsing SSDP schema for http://192.168.1.120:34400/device.xml
Mar 25, 2021 10:20:43.910 [9448] DEBUG - HTTP requesting GET http://192.168.1.120:34400/device.xml
Mar 25, 2021 10:20:43.922 [9448] DEBUG - HTTP 200 response from GET http://192.168.1.120:34400/device.xml
Mar 25, 2021 10:20:43.922 [9448] DEBUG - NetworkServiceBrowser: found 1 SSDP devices via http://192.168.1.120:34400/device.xml
Mar 25, 2021 10:20:43.922 [9448] DEBUG - NetworkServiceBrowser: SSDP arrived: 192.168.1.150 (xTeVe)
Mar 25, 2021 10:20:43.923 [9448] DEBUG - NetworkServiceBrowser: couldn’t find SSDP service URL for 192.168.1.1
Mar 25, 2021 10:20:43.923 [9448] DEBUG - NetworkServiceBrowser: PLAYER arrived: 192.168.1.150
Mar 25, 2021 10:20:43.950 [9448] DEBUG - NetworkServiceBrowser: Parsing SSDP schema for http://192.168.1.169:8060/
Mar 25, 2021 10:20:43.950 [9448] DEBUG - HTTP requesting GET http://192.168.1.169:8060/
Mar 25, 2021 10:20:43.967 [9448] DEBUG - HTTP 200 response from GET http://192.168.1.169:8060/
Mar 25, 2021 10:20:43.967 [9448] DEBUG - NetworkServiceBrowser: found 1 SSDP devices via http://192.168.1.169:8060/
Mar 25, 2021 10:20:43.967 [9448] DEBUG - NetworkServiceBrowser: SSDP arrived: 192.168.1.169 (Living Room)
Mar 25, 2021 10:20:44.294 [9448] DEBUG - NetworkServiceBrowser: Parsing SSDP schema for http://192.168.1.176:8060/
Mar 25, 2021 10:20:44.294 [9448] DEBUG - HTTP requesting GET http://192.168.1.176:8060/
Mar 25, 2021 10:20:44.311 [9448] DEBUG - HTTP 200 response from GET http://192.168.1.176:8060/
Mar 25, 2021 10:20:44.311 [9448] DEBUG - NetworkServiceBrowser: found 1 SSDP devices via http://192.168.1.176:8060/
Mar 25, 2021 10:20:44.311 [9448] DEBUG - NetworkServiceBrowser: SSDP arrived: 192.168.1.176 (Bedroom)
Mar 25, 2021 10:20:44.444 [9448] DEBUG - NetworkServiceBrowser: Parsing SSDP schema for http://192.168.1.13:80/upnp/BasicDevice.xml
Mar 25, 2021 10:20:44.444 [9448] DEBUG - HTTP requesting GET http://192.168.1.13:80/upnp/BasicDevice.xml
Mar 25, 2021 10:20:44.469 [9448] DEBUG - HTTP 200 response from GET http://192.168.1.13:80/upnp/BasicDevice.xml
Mar 25, 2021 10:20:44.469 [9448] DEBUG - NetworkServiceBrowser: found 1 SSDP devices via http://192.168.1.13:80/upnp/BasicDevice.xml
Mar 25, 2021 10:20:44.469 [9448] DEBUG - NetworkServiceBrowser: SSDP arrived: 192.168.1.13 (SuPlex-Host)

That switch support LACP, any reason you down want to use it for teaming?

13

I figured out how to setup LACP with my Switch last night on another machine, using Windows NIC Teaming. I’m going to set this up today on my Plex host and see what happens. I’ll report my findings.

Thanks!

14

was referring to this setting

image

15

I’ve never had that option before, that I can recall anyway.

We’ll see what LACP does for me and go from there.

Edit I see the option now. I was looking under Remote Access and not Network. Probably would have solved my issue, but I’d rather just use LACP anyway. No real need to have the NICs separated.