Hello, I currently have a home server mainly for media, in which I have an SSD for the system and 2 6TB hard drives set up in raid 1 using mdadm, its the most I can fit in the case. I have been getting interested in ZFS and wanting to expand my storage since it's getting pretty full. I have 2 12TB external hard drives. My question is can I create a pool (I think that's what they are called), using all 4 of these drives in a raidz configuration, or is this a bad idea?

(6TB+6TB) + 12TB + 12TB, should give me 24TB, and should work even if one of the 6TB or 12TB fails if I understand this correctly.

How would one go about doing this? Would you mdadm the 2 6TB ones into a raid 0 and then create a pool over that?

I am also just dipping my toes now into Nixos so having a resource that would cover that might be useful since the home server is currently running Debian. This server will be left at my parents house and would like it to have minimal onsite support needed. Parents just need to be able to turn screen on and use the browser.

Thank you