Hello,

I am going to upgrade my server, taking advantage of the fact that I am going to be able to put more hard disks, I wanted to take advantage of this to give a little more security (against loss) to my data.

Currently I have 2 hard drives in ext4 with information, and wanted to buy a third (same capacity all three) and place them in raid5, so that in the future, I can put more hard drives and increase the capacity.

Due to economic issues, right now I can only buy what would be the third disk, so it is impossible for me to back up the data I currently have.

The data itself is not valuable, in case any file gets corrupted, I could download it again, however there are enough teras (20) to make downloading everything a madness.

In principle I thought to put on this server (PC) a dietpi, a trimmed debian and maybe with mdadm make the raid. I have seen tutorials on how to do it (this for example https://ruan.dev/blog/2022/06/29/create-a-raid5-array-with-mdadm-on-linux ).

The question is, is there any way without having to format the hard drives with data?

Thank you and sorry for any mistakes I may make, English is not my mother language.

EDIT:

Thanks for yours answers!! I have several paths to investigate.

  • @catloaf@lemm.eeEnglish
    10•6 months ago

    You can do RAID 5 with three disks. It’s fine. Not ideal, but fine.

    My biggest concern is what OP is using as a server. If these disks are attached via USB, they are not going to have reliable connections, and it’s going to trigger frequent RAID rescans and resyncs any time one of the three disks drops out. And the extra load from that might cause even more drops.

      • @catloaf@lemm.eeEnglish
        2•6 months ago

        They didn’t say USB, but they did say dietpi. I’ve never played with a rpi, but I don’t think they have SATA or SAS ports, only USB.

          • LoboAureoOPEnglish
            1•6 months ago

            Yes, dietpi is main for SBC, but also has an iso for PCs, its and old computer with 6 sata ports