Maybe do some trials at: https://carfax.org.uk/btrfs-usage/
I usually bought bigger HDD, typically twice the size, so long time ago 500GB then some 2TB then several 4TB
I currently do not use RAID anymore, instead clone max 8TB filesystems, all Btrfs.
With the btrfs-progs tooling, it is possible to convert the filesystem on-the-fly, no unmounting needed. Add an 8TB HDD for example and make the 2TB+4TB+8TB RAID1
If not Btrfs yet, offline btrfs-convert can convert from Ext4 to Btrfs. You need some free space for that as new Btrfs metadata needs space. This is also true for online conversion (via btrfs balance).
As already indicated, all via USB is far from ideal, it works, but risk that something will fail sometime w.r.t. RPi4 UBS3 or USB-SATA chipset is not unthinkable. Then RAID won't help as the hardware USB chain is also not multi-path.
I usually bought bigger HDD, typically twice the size, so long time ago 500GB then some 2TB then several 4TB
I currently do not use RAID anymore, instead clone max 8TB filesystems, all Btrfs.
With the btrfs-progs tooling, it is possible to convert the filesystem on-the-fly, no unmounting needed. Add an 8TB HDD for example and make the 2TB+4TB+8TB RAID1
If not Btrfs yet, offline btrfs-convert can convert from Ext4 to Btrfs. You need some free space for that as new Btrfs metadata needs space. This is also true for online conversion (via btrfs balance).
As already indicated, all via USB is far from ideal, it works, but risk that something will fail sometime w.r.t. RPi4 UBS3 or USB-SATA chipset is not unthinkable. Then RAID won't help as the hardware USB chain is also not multi-path.
Statistics: Posted by redvli — Sat Jan 10, 2026 6:51 pm