Here we are trying to collect various tips, which could help those users who are only using Plex within their home network, but see the message from the title anyway.
- when using virtualization/containers for the server, use “Host networking”. If you use “Bridge” instead, a layer of NAT will be inserted, which moves your server into a different network than your local clients are. The server being in a different network is considered “remote access”.
- Verify that you are not affected by “DNS rebinding protection”. Because if you are, clients are not able to use secure connections in your local network. https://support.plex.tv/articles/206225077-how-to-use-secure-server-connections#toc-4
- Check for other network components which could cause a split of your network. More than one “router”-type device, wireless bridges, a separate Mesh router, coax network bridges etc. could all be configured to perform NAT. NAT should only be performed in your main internet router, and nowhere else in your home network.
- Ensure that your home network address is in one of the ranges, which are explicitly designated for private use: https://en.wikipedia.org/wiki/Private_network
- When using the web app, check browser features or plugins which could obscure/hide a device’s IP address (e.g. iOS WLAN settings, MacOS: System Settings > Privacy & Security > Local Network > Chrome/Safari)
- if you use the local web app, load it into your browser using the private IP address of your server. Do not use a domain name.
- if the difficulties occur in the Plex web app specifically, look at this as well: https://forums.plex.tv/t/important-note-about-chrome-and-firefox-local-network-access/933264/1
- On MacOS, both the web browser, the “Plex for Mac” desktop app (if used), and Plex Media Server need the privilege to access the local network: System Settings > Privacy & Security > Local Network
- do always check if the difficulty is caused by the use of VPN software of any type. (Tailscale, Wireguard etc.pp.)
Disable this completely and re-test all components after restarting/rebooting them. - if you use a custom/manual port forwarding rule in your router for internet/remote access, DON’T use the port number 32400 for the external/WAN port.
Instead, pick a random number from 20000–50000. Then put this number into your port forwarding as the “external/WAN” port number (the “internal/LAN” port number must always remain at 32400!).
Then put the exact same external port number into the Plex configuration at Settings - [server name] - Remote Access - ‘Show Advanced’ - “Manually specify public port” - When using Windows as your server platform, check the properties of its network connection. It must be classified as “private”, not as “public”. Otherwise you won’t be able to connect with your client directly.
