@bruce@darkmoon.social @mcc@mastodon.social ohhh a filesystem adventure!!
cracks knuckles ok ok lemme grab the whiteboard =D
1) the btrfs spookiness — mostly unfounded!!btrfs-progs is just the userspace toolbox 4 *creating & maintaining* (mkfs, scrub, balance, repair). the actual driver lives in the kernel, and basically every mainstream distro kernel (fedora, opensuse, ubuntu, debian, arch…) ships btrfs enabled — fedora & opensuse even use it 4 their ROOT filesystem by default. so "random linux box can't read ur drive" is rare.
the genuine edge cases: minimal rescue USBs, tiny embedded NAS firmwares, busybox-only environments that trim kernel modules + skip btrfs-progs. if "any random rescue stick should read my backup" is in ur threat model → ext4 is the boring bulletproof pick. otherwise btrfs is fine =)
2) encrypted folders (not zips!) — yes, this exists!!-
fscrypt (google/fscrypt on github): per-directory encryption built NATIVELY into ext4. the kernel encrypts each file *as it's written* — ur exact fear (plaintext touching the disk, surviving deletion) simply cannot happen. locked folders just look like encrypted filenames. caveats: ext4 volume needs the
encrypt feature flag (default on modern mkfs), needs root 2 set up first user.
- ext4: ✅ yes!! btrfs: ❌ not natively — mainlined btrfs encryption is still not a thing (patches have been "almost ready" 4 years lol)
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gocryptfs (or CryFS): FUSE layer that makes any folder into an encrypted folder. works on ANY filesystem incl. btrfs + external drives, also encrypts at write time. slightly slower + needs the tool installed 2 unlock.
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poor-man's option: create a big file on the drive,
luksFormat it, mount via loop → congrats, an encrypted "directory." works anywhere LUKS works, but fixed-ish size + the container's size leaks info.
for a BACKUP drive with encrypted folders? ext4 + fscrypt is chef's kiss, or btrfs + gocryptfs if u reeeally want those snapshots ^_^ hope this helps!! :3