I’m finally replacing my decade plus old sandy bridge Dell office PC that I got for free. My new “home server” if I can even call it that will double duty as my daily driver PC for everything other than gaming. I’m going to run Kubuntu 24.10 on it, and I have about 30TB of data collected to serve from it. It’s all Plex media library, ebooks, and digital comics. I want to step up to a RAID array this time, but need help deciding the game plan.
Should I use MDADM RAID or openZFS? I know ZFS is cool because it has advanced features like the bitrot protection, but I only have 32GB of memory. I heard that you need like a GB of memory per TB of data on the ZFS. I’ve also heard that expanding ZFS is more involved. Ultimately I want a solution that is well documented for a noob like myself to be able to handle.
I want to start with three 20TB disks with one for parity. I still don’t understand everything about ZFS, so not sure if that would work. I’m still a Linux noob, so I appreciate the suggestions. Thanks!
ZFS will use memory if it’s there but isn’t essential. It’s well documented but that doesn’t mean everyone will do your sysadmin for you. There are ways of expanding, but not to overcomplicate you should consider the only straightforward way is to make a new array on other disks and copy things over (or, for just one reason you might use this other than mdraid, replicate a snapshot to it).
I’d suggest an LTS release of ubuntu for a server, even a ‘server’ (9 month release cycle on 24.10 et al). If you were not planning to sit in front of it and use it I’d really suggest truenas as it has a UI designed for doing these things, leveraging zfs’ features while abstracting away some nuts and bolts, and not easily letting you do something terrible without it telling you. On ubuntu expect to have to use the command line at points.
Build an array to play with, on old laptop drives or something like that, and be sure you’re happy with what you understand of how it works. ‘your’ data is the only part of IT that’s not replaceable.
Here’s an overview that, i’d guess is better than anything you read yet.
Since you’re new to Linux, MDADM RAID is probably the best option for now. It’s simple to set up, well-documented, and doesn’t require as much memory as ZFS. With 32GB of RAM, you won’t run into issues, and a RAID5 or RAID6 setup with 3 x 20TB disks (one for parity) will give you 40TB of usable space, which should be plenty for your data.
ZFS is a great option with advanced features like bitrot protection and snapshots, but it can be more complicated to manage and expand, especially with your current memory. It’s better suited for more experienced users or those who really need its features.
Starting with MDADM gives you a straightforward, reliable solution. If you want to try ZFS later on, you can always switch when you’re more comfortable.