When you install PMS and claim the server with a Plex account and start to load it up with media, it exists on your list of Authorized Devices, Servers.
https://app.plex.tv/desktop#!/settings/devices/pms
If at some point you get frustrated and wipe the computer clean, and then if you install a new PMS that you claim, then your list of Authorized Devices would grow by one. The existence of those two servers (duplicates) leads to further login problems that cause the user to create a new plex account trying to fix it, thus ending up with duplicate accounts and servers so to speak.
Sound familiar?
On top of those possibilities, you’ve layered a docker. The outcome of just the docker and nothing else, is that so far Plex can’t define the scope of the network. It get’s stuck trying to do so in your log. On my NAS, Plex finds the en0 and lo interfaces. On your system, Plex finds a dozen or so, repeatedly, and never stops trying..
Nov 08, 2019 09:50:24.969 [0x7fa3d1ffb700] DEBUG - Detected primary interface: 192.168.1.3
Nov 08, 2019 09:50:24.969 [0x7fa3d1ffb700] DEBUG - Network interfaces:
Nov 08, 2019 09:50:24.969 [0x7fa3d1ffb700] DEBUG - * 1 lo (127.0.0.1) (loopback: 1)
Nov 08, 2019 09:50:24.969 [0x7fa3d1ffb700] DEBUG - * 2 eno1 (192.168.1.3) (loopback: 0)
Nov 08, 2019 09:50:24.970 [0x7fa3d1ffb700] DEBUG - * 5 br-45d34910732b (172.20.0.1) (loopback: 0)
Nov 08, 2019 09:50:24.970 [0x7fa3d1ffb700] DEBUG - * 6 br-97dac6cba072 (172.23.0.1) (loopback: 0)
Nov 08, 2019 09:50:24.970 [0x7fa3d1ffb700] DEBUG - * 8 docker0 (172.17.0.1) (loopback: 0)
Nov 08, 2019 09:50:24.970 [0x7fa3d1ffb700] DEBUG - * 202 br-79dc7257b963 (172.19.0.1) (loopback: 0)
Nov 08, 2019 09:50:24.970 [0x7fa3d1ffb700] DEBUG - * 1 lo (::1) (loopback: 1)
Nov 08, 2019 09:50:24.970 [0x7fa3d1ffb700] DEBUG - * 2 eno1 (2a02:a452:e960:1:96c6:91ff:fea3:2d56) (loopback: 0)
Nov 08, 2019 09:50:24.970 [0x7fa3d1ffb700] DEBUG - * 2 eno1 (fe80::96c6:91ff:fea3:2d56%eno1) (loopback: 0)
Nov 08, 2019 09:50:24.970 [0x7fa3d1ffb700] DEBUG - * 5 br-45d34910732b (fe80::42:63ff:fe47:8f82%br-45d34910732b) (loopback: 0)
Nov 08, 2019 09:50:24.970 [0x7fa3d1ffb700] DEBUG - * 6 br-97dac6cba072 (fe80::42:53ff:fe46:1f61%br-97dac6cba072) (loopback: 0)
Nov 08, 2019 09:50:24.970 [0x7fa3d1ffb700] DEBUG - * 18 vethd61b7aa (fe80::80d6:e9ff:fe38:231a%vethd61b7aa) (loopback: 0)
Nov 08, 2019 09:50:24.970 [0x7fa3d1ffb700] DEBUG - * 26 veth937c345 (fe80::9853:8ff:fee6:36f7%veth937c345) (loopback: 0)
Nov 08, 2019 09:50:24.970 [0x7fa3d1ffb700] DEBUG - * 6290 veth89a3c4d (fe80::cc1c:88ff:fee1:e1c5%veth89a3c4d) (loopback: 0)
Nov 08, 2019 09:50:24.970 [0x7fa3d1ffb700] DEBUG - * 202 br-79dc7257b963 (fe80::42:3dff:fe56:5293%br-79dc7257b963) (loopback: 0)
Nov 08, 2019 09:50:24.971 [0x7fa3d1ffb700] DEBUG - * 206 vethd7538b8 (fe80::f043:a1ff:fe67:8d10%vethd7538b8) (loopback: 0)
Nov 08, 2019 09:50:24.971 [0x7fa3d1ffb700] DEBUG - * 208 vethfa5da7d (fe80::6824:aeff:fee9:58ba%vethfa5da7d) (loopback: 0)
Nov 08, 2019 09:50:24.971 [0x7fa3d1ffb700] DEBUG - * 210 veth732173e (fe80::94d5:f1ff:fef7:304b%veth732173e) (loopback: 0)
Nov 08, 2019 09:50:24.971 [0x7fa3d1ffb700] DEBUG - * 212 vetheefd41b (fe80::289f:d8ff:fe26:cf86%vetheefd41b) (loopback: 0)
What I can suggest are the website articles below that I use myself. Given the level of configuration needed to create that list of interfaces, I am humbled by your knowledge.
https://support.plex.tv/articles/200288586-installation/
https://support.plex.tv/articles/201105343-advanced-hidden-server-settings/
