Hello, short question is that possible with bcachefs, I know it isn't with btrfs: zpool status pool: nc_storage state: ONLINE scan: scrub repaired 0B in 1h43m with 0 errors on Wed May 15 05:58:45 2019 config: NAME STATE READ WRITE CKSUM nc_storage ONLINE 0 0 0 mirror-0 ONLINE 0 0 0 j1d03-hdd ONLINE 0 0 0 j2d03-hdd ONLINE 0 0 0 mirror-1 ONLINE 0 0 0 j1d04-hdd ONLINE 0 0 0 j2d04-hdd ONLINE 0 0 0 mirror-2 ONLINE 0 0 0 j1d05-hdd ONLINE 0 0 0 j2d05-hdd ONLINE 0 0 0 mirror-3 ONLINE 0 0 0 j1d06-hdd ONLINE 0 0 0 j2d06-hdd ONLINE 0 0 0 [...] mirror-16 ONLINE 0 0 0 j1d18-hdd ONLINE 0 0 0 j2d18-hdd ONLINE 0 0 0 logs mirror-9 ONLINE 0 0 0 j1d00-ssd ONLINE 0 0 0 j2d00-ssd ONLINE 0 0 0 cache j1d02-ssd ONLINE 0 0 0 j2d02-ssd ONLINE 0 0 0 In this case I can lose a HBA Controller or a complete JBOD without losing data. I think thats important in datacenters. The same is with other RAID levels when the cross the harddisk over several jbods. thanks in advance, best regards Stefan