Maybe a dumb question, but how is this better than having your files on a nas? I have a nas and just play my media files from there on my tv and laptop.
What do I get from having jellyfin?
Kodi/XBMC has been providing that for like 20 years though...
What jellyfin does provide that Kodi doesn't is on the fly transcoding for watching on mobile device and remote access. If you don't need that, Kodi might be a better choice providing a far wider array of features.
You're not wrong but there are still drawbacks to Kodi where Jellyfin ends up being better. In my use case, with 5 tvs in the house, 2 are hooked up to Nvidia shield tvs but the other 3 are Chromecast w/ Google TV which have very limited storage unless I want to spend a fortune in hubs for each one to add a USB drive or micro SD.
With kodi installed I would regularly hit the storage limit of the device and have all kinds of weird bugs. Just as an example I had my daughter set up with a kids only account, but account switching would cause Kodi to become unresponsive for anywhere from 30 seconds to having to do a hard reset of the device. Jellyfin gives me the same access to my library with a lighter, more streamlined, persistent interface across devices and with easy and fast profiles. It still allows me to keep a pi as the host so the whole setup is low power (important for me as we're on solar, every watt helps!)
I don't really need the Kodi plugins I used to have if the main purpose of streaming my local content isn't smooth and simple for the family. This is coming from a long time XBMC user, I've been running it since my original modded Xbox in the early 2000s.
Then you are doing it wrong. I have three instances of Kodi, one of them on completely hard drive less machine booted via PXE, the other two are Pis with minimal is on an SD card. All the media's are stored on a NAS, and all the metadata is shared between the instances on MySQL, all of it (profiles, views, etc) shared across all the instances.,
"Wrong," or a matter of preference and willingness to sink time into the project. Your setup sounds great, but it's also easy enough for me to do a simple apk install for Jellyfin and host it on the pi that already has my network shares vs spending the time setting up a database and a local DHCP server etc. etc. Netboot is great but with a fraction of the setup with Jellyfin my needs were met, which was my original point. Also how many end users will take this route? Realistically not many.
Don't get me wrong this was something i'd totally be into a decade ago so I get where you're coming from, love the idea of having the metadata and everything scraped centralized, but what I have works and it's easyyyyyyyy 🤷♂️
I just recently set up jellyfin as a way for my family to access the stored media outside of my house. Our current Networking setup doesn't play nicely with VPNs so this was an easy way to do that.
NAS vs Jellyfin isn't really how to look at it. You still need to have the files stored somewhere, and Jellyfin can just access the files from wherever you store them. As others say, Jellyfin adds some convenience. Think of it like Netflix but for your local files. You can install an app on your phone, laptop, tablet, or just access Jellyfin's built in web interface on laptop/etc... It pulls down thumbnails and show information automatically, and you can set up different accounts/profiles to track show progress and favorites for multiple people.
It keeps track of which files you've played (e.g. to automatically pick the next episode in a series), it automatically downloads metadata and cover art so you have a nice browsing interface, it manages multiple profiles so that e.g. you can limit your kids' access to only G and TV-Y or filter out genres a user doesn't like, it lets you set parental controls to limit the amount of time watched in a day (or disable it at certain times of day), etc.
But, Jellyfin/Plex has the advantage you get a nice pretty "app" that works on your TV/Roku/AndroidTV/etc. It handles transcoding if needed, keeps track of what you have watched, and lets you know when new things pop up.
I use both plex and jellyfin and my files are on a nas. Previously truenas but now synology. I just mount my collection over smb to my Intel nuc with quick sync so that Plex/jellyfin can provide me and my friends a slick UI as well as transcoding (can store stuff in hevc, flac, 5.1 or 7.1 dts hd ma and not worry about codec support on each device), a nice web player with subtitles /audio track selection, and nice apps on every device to access the collection.
But yeah NAS and jellyfin aren't mutually exclusive, many people use them together.
Jellyfin/Plex/Emby turn your media collection into your own personal Netflix. They have apps for multiple platforms, you can setup user access controls, parental controls based off age ratings, track progress through shows and movies, search and organize based off genre and tags, and much more. Also, they can handle on the fly transcoding of the media, so if a device doesn't support a specific codec or container it can be converted into another, or if the user is on a poor Internet connection which can't handle a 4K video, it can downgrade the quality to make it easier to stream on the poor connection.
Overall, they just provide a better experience when consuming media.
Also, they're not exclusive. I have a nas with more space but essentially no ability to transcode media, so I've mounted that volume via NFS on a laptop I run jellyfin which gives me excellent transcoding and a very smooth experience.