On Fri 14 Aug 2020 at 08:25:20 (+0300), Andrei POPESCU wrote: > On Mi, 12 aug 20, 20:14:03, rhkra...@gmail.com wrote: > > I'm getting closer to setting up a consistent backup plan, backing up to an > > external USB drive. I'm wondering about a reasonable filesystem to use, I > > think I want to stay in the ext2/3/4 family, and I'm wondering if there is > > any > > good reason to use anything beyond ext2? > > In my opinion using ext2 in 2020 is mostly pointless, beyond the rare > situation where some software doesn't support ext4 (e.g. some odd/old > bootloader, other OSs, etc.). > > Because it is getting significantly less use support for it is also more > likely to bit rot. > > As far as I know ext3 is mostly ext2 with journalling added. > > In comparison ext4 was developed from scratch with journaling and > support for other newer techniques, like better allocation of space to > prevent fragmentation and improve performance.
If you create your backup partitions on a newer distribution, just check that wheezy can mount it before you start filling it up. There are one of two options that wheezy kernels can't handle in ext4, though I don't know whether any of them get enabled by default. man ext4 for details. Ditto for any encryption scheme you might use. > > (Some day I'll try ZFS or BTRFS for my "system" filesystems, but don't see > > any > > point (and don't want to learn) either of them at this point -- I don't see > > much need for a backup filesystem.) > > As has been stated already, both btrfs and ZFS have built-in bitrot > protections that are very useful for backups and archives. To achieve > the same level of protection on ext4 you need additional tools. I'm dubious whether I shall ever start using these filesystems. I create multiple backups on ext4 filesystems on LUKS, and keep MD5 digests of their contents. Would that qualify as your "additional tools"? Cheers, David.