Choose storage for your Plex or Jellyfin server

1. Start with the library you actually have

Measure the folders you plan to store, then add your expected growth and space for versions or extra copies. Movie counts are a poor shortcut because codecs, bitrates and runtimes vary. For an illustrative 6TB library growing by 2TB per year, two years of growth brings the files to 10TB before working headroom. That does not mean a 10TB drive is enough: advertised capacity, filesystem overhead and redundancy all affect usable space. Decide on the array layout before choosing drive capacity, and budget for a separate backup destination.

2. Give media files and server files different jobs

A large HDD can be a sensible home for media when its sustained read performance covers your playback workload. Jellyfin recommends SSD storage for its own application files because those accesses are less sequential. Keep capacity for three separate needs: the media library, the server database and artwork, and temporary transcode files. Plex notes that preview thumbnails and downloads can make its data directory much larger; inspect your actual usage rather than assuming one SSD size fits every server. For Plex temporary transcoding, follow its documented free-space requirement and location restrictions. A faster SSD will not by itself fix an unsupported codec or an overloaded transcoding processor.

Source: Jellyfin hardware and storage guidance

3. Choose a recovery plan, not just a parity drive

A mirror or parity array can keep files available through supported drive failures, but it is not an independent backup. Keep another copy of irreplaceable video, photos and server configuration, and decide how much time you could spend restoring the rest. SnapRAID is synchronized periodically: new files on a failed disk added after the last sync are not protected, and later changes elsewhere can affect recovery. It should not be described as identical to a live parity array. For an Unraid array, each parity disk must be at least as large as the largest data disk. Follow the documentation for your chosen system, including its checks and recovery procedure.

Source: SnapRAID: recovery and changes since the last sync

4. Buy the exact interface and capacity your server supports

For a SATA NAS or desktop array, shortlist documented CMR SATA models and check the enclosure's current compatibility list. A cheap SAS drive needs a compatible SAS controller; an ordinary SATA port is not enough. Compare equal capacities and conditions using current prices, then calculate the bill for every drive you need. A low unit price can still mean spending more overall. New, used and renewed offers have different seller and warranty considerations. Shucking adds uncertainty about the internal drive and warranty, so compare a known internal model before deciding the saving is worthwhile. More expensive or larger drives are not automatically the right choice for a small library.

5. Compare the whole storage purchase

The examples below illustrate capacity arithmetic, not tested stream counts or a universal build recommendation. Two 12TB drives in a mirror provide 12TB before overhead, while four 8TB drives in RAID 5 provide 24TB. Those layouts need different numbers of bays and have different recovery tradeoffs. Include the enclosure, server SSD if needed, backup storage and any network changes in your budget. Reuse suitable hardware when it meets the requirements. Before buying a NAS to run Plex itself, verify support for your player devices, codecs, subtitles and intended transcoding features; a NAS storing the files and a separate server running Plex are also possible.

Illustrative drive layouts, before filesystem overhead

Frequently Asked Questions

Sources

• Jellyfin: hardware selection and storage roles
• Plex: why the server data directory grows
• Plex: temporary transcoder storage requirements
• Plex: NAS devices and limitations
• SnapRAID: synchronization and recovery limitations
• Unraid: array devices and parity disk sizing