Re: Encrypted software RAID1 with Debian Stretch

[Wols Lists <antlists@youngman.org.uk>]

On 14/09/17 12:08, Nix wrote:
>> The rule is simple - don't abuse your tools, and btrfs - USED WITHIN ITS
>> > LIMITATIONS - is a powerful and reliable file system.

> Yeah, but... if you avoid the advanced features, why use btrfs? In
> particular, why use it *for a backup medium* (where such features are
> distinctly less useful than on a non-backup medium)?

Because, if you use snapshots and an "in-place rsync" (which overwrites
the part of files which have changed, rather than replacing the file by
default), then each snapshot is a full backup, but only uses the space
of an incremental.

The OP was building a backup server, so all their live data is
elsewhere, and provided you look after your backups, this will give you
a very cheap and effective backup system.

(Add to which I know nothing about XFS and ZFS, other than ZFS needs
gobs of ram and why would you want to over-provision a server that isn't
switched on unless you're backing up.)

Cheers,
Wol