Is there a limit to how many connections can access/play a single file from the Plex Server?
the limit how many connections are supported is dependend on a bunch of things:
- throughput of your storage system
- upload capacity of your internet connection (for remote clients)
- the throughput of your home network (for local and remote clients)
- the cpu speed or your server computer in case transcoding is needed
- the type of client which is playing something
- the bitrate setting in the client
- whether there are subtitles are activated on a client or not and if the client is able to render the subtitles by itself or if it needs the server to step in and ‘burn in’ the subtitles into the video
All of the above depends in turn on the quality and file format your media files are stored on your machine.
https://support.plex.tv/hc/en-us/articles/201774043-What-kind-of-CPU-do-I-need-for-my-Server-
Start small and test Plex slowly. You can do so perfectly fine without buying any licenses. So you can learn how Plex behaves and what is best for streaming through Plex in terms of file formats etc pp.
