DAS/RAID Questions and Opinions

[Unamuseumed]

Hey there, looking to get some advice and opinions on implementing direct attached storage and RAID configs as a relative newbie...

Background is I've finally got bitten by the Jellyfin bug and got a free BD drive to start ripping .mkv files and serving them locally. I run Macs almost exclusively and have an M1 Mac Mini always hooked up that I figured would be perfect for this purpose (it's also for generic office work but we won't be streaming at the same time). Drives wise I have a whole melange of drives in various sizes accumulated over the years from projects (I do a lot of retro PPC Mac stuff).

Since I've already got the Mini and it's pretty power efficient, I figured I'd skip the NAS angle and just do DAS from the Mini. Right now I have 2TB external WD HDD acting as storage, but I'd like to increase that. What I'm thinking is to shuck that external drive so I can combine that 2TB 2.5 SATA HDD with a 1TB 2.5 SATA HDD I harvested from an old laptop, along with a 1TB 2.5 SATA SSD that's currently in an old iMac (friend gave it to me, the SSD was installed a few years ago to replace a failing HDD, and now it's solid gold in there).

My questions would be...

• Should I instead go for NAS instead of DAS? This is mostly for home use...
• Is there an issue combining HDDs and SSDs in a DAS enclosure?
• What RAID configuration should I go with in this instance?

I also have an external 1TB SSD (NVME based) that I could look at shucking, but that seems like overkill, and then I'd need to find a 4 bay SATA+ 2 bay NVME enclosure... Anywho, any thoughts or experience would be appreciated!

 

[continuum]

Personally speaking, I find RAID is good for availability but as far as home use goes, availability is actually not that big a deal. Having a separate backup is probably easier/cheaper/equally valuable.

Combining SSD and HDD is more of a NAS-specific/whatever software specific you are using. For streaming media I find SSD to be not worth the cost.

 

[evan_s]

Classic raid modes are designed around drives of the same size. There are some options for mixing and matching drive sizes. For a DAS with hardware raid you are probably going to be limited to some sort of JBOD (Just a bunch of disks) configuration where you have no redundancy so you get the combined size of all the drives but a single drive failure can take all your data. If you want redundancy you'd want to go for a mirror or Raid 1 where it just stores the same info on both drives so if one drive fails you have your data on the other drive. This would combine two of the 2tb drives to give you 2tb of storage. If you want redundancy but without loosing as much space you can look at RAID 5 which uses 1 drive for redundancy and the other drives for data so with four 2tb drives you'd end up with 6tb of storage.

You'd have to decide if you want/need redundancy or not. Theoretically, you can just rip all your stuff again but that could be quite a bit of effort.

You might also want to consider if it's worth trying to piece together all of these old small drives or if a 2 bay nas/das with a couple of larger 4 or 6tb drive might be a better option than a 4 bay NAS with all your assorted drives in it.

An actual NAS instead of a DAS attached to your Mac Mini would give you different options software wise. The NAS might also support containers or dockers to add other small server things to your network. It would probably also be more setup and forget than rolling your own on your Mac Mini.