Author: Martin Steigerwald Date: To: Devuan ML Subject: Re: [DNG] Backup methods for Devuan
Hi!
Simon Hobson - 08.06.24, 13:55:35 CEST: > > It sounded good until the deduplication and compression. I view
> > deduplication and compression as negative parity bits, such that even
> > in a text file, one flipped bit messes up everything.
>
> (Mostly) agreed.
> Both have their place, and that’s a decision for the individual to make
> based on their own priorities and limitations. On the latter, I have
> not so fond memories (in a smallish business) of chasing tape capacity
> developments with “limited budget” - and without compression I’d have
> not been able to do some of the backups we did, or would have needed
> more tapes (which is a problem if you don’t have a trained monkey you
> can leave overnight to swap tapes).
For me the redundancy part comes in by using several disks, some of them
stored at different locations.
But interesting thought indeed that deduplication and compression can make
a backup and also original data more fragile. Thanks, Steve. I am still
using compression with BTRFS also for main production data. With that 4 TB
NVME SSD inside my main laptop I could reconsider that choice. Hmm… let's
see.
Indeed Parity Archive Volume Set adds redundancy to make backups more
reliable, especially those done on optical disks via Disk Archive (dar) or
DVD Backup (dvdbackup), Bluray Backup (bluraybackup). A tool for working
is parity archives is packaged in par2.