>> [...] Note that it IS a shingled drive, so fine for backup, >> much less so for anything else. It is fine for backup especially if used as a tape that is say divided into partitions and backup is done using 'dd' (but careful if using Btrfs) or 'tar' or similar. If using 'rsync' or similar those still write a lot of inodes and often small files if they are present in the source. >> I'm not sure whether btrfs would be a good choice or not ... > [...] btrfs did NOT play well with raid 5/6. It may be old > info, but: > https://superuser.com/questions/1131701/btrfs-over-mdadm-raid6 That seems based on some misunderstanding: native Btrfs 5/6 has some "limitations", like most of its volume management, but running over MS RAID 5/6 is much the same as running on top of a single disk, so fine. MD RAID 5/6 takes care of redundancy so there is no need to have metadata in 'dup' mode. Using RAID 5/6 with SMR drives can result in pretty huge delays (IIRC a previous poster has given some relevant URL) on writing or on rebuilding, as the "chunk" size is very likely not to be very congruent with the SMT zones.
