It's FUD. ext4 with LUKS, which is what pretty much everyone is using on a deskt... (2024)

Ubuntu's installer for a long while set up an "encrypted home directory" using eCryptFS, i.e., file-level encryption on top of ext4. That's the thing Dropbox is finding painful to support.

Migrating away from that to block-level "full disk" encryption basically requires copying all your files. If you're using <50% of your disk and you feel comfortable doing tricks with partition resizing you can do it, otherwise the best approach is to back up your files (hopefully to encrypted media...) and restore them.

Just FYI: Ext4 has file-level encryption built-in now [1, 2], so 'encrypted ext4' is actually different from encfs and ecryptfs.

[1]: https://www.kernel.org/doc/html/v4.19/filesystems/fscrypt.ht...

[2]: https://wiki.archlinux.org/index.php/ext4#Using_file-based_e...

It's potentially misleading phrasing. "Unencrypted ext4" means that the filesystem Dropbox sees has to be actual ext4, not an encryption layer on top. There can be an encryption layer under it, and generally full-disk encryption works that way, by encrypting a block device and letting you run whatever filesystem you want on top.

"Unencrypted or decrypted ext4" might be slightly more accurate (although I guess it maybe sounds like you need to remove encryption, not that you just need to decrypt files in memory).

In fairness, it's pretty difficult (read: impossible) to enable full-disk encryption on an NVME drive (read: most Ultrabooks including the Dell XPS "Developer Edition.")

https://www.dell.com/community/Linux-Developer-Systems/XPS-1...

Full-disk encryption usually means encryption at the block layer below the filesystem. It doesn't actually have to cover the full disk.

There is almost always at least one unencrypted partition on machines with full-disk encryption, since the boot loader and then the decryption routine have to be launched from somewhere. And yes, OEM recovery partitions or similar laptop-specific needs are another case.

Full-partition would be a more accurate term than full-disk.

If you've ever installed gentoo, then it shouldn't be too difficult. Follow the installation steps but instead of partitioning the harddrive and installing into one partition, make the filesystem across the whole harddrive (eg. `mkfs.ext4 /dev/sda`) and install into that. The system on the laptop (Lenovo X61) is really old (like 8 years at least), back then I needed to perform some manual steps to ensure the initrd has the necessary tools so it can mount an decrypt the root partition, this is probably not necessary anymore. Upgrading kernels has to be done carefully, because I must make sure the USB stick contains a compatible kernel. I also need to configure the UEFI boot menu so that it knows where to find the kernels. Fun stuff.

I wouldn't know where to start if you want to use ubuntu or another more user friendly distribution though.

You _can_ do it with libreboot on ancient thinkpads, but it requires a decent time (or money) investment and some know-how. https://libreboot.org/docs/gnulinux/encrypted_trisquel.html

Add it to the already long list of software that misbehaves over NFS.

Ceph/RBD with the filesystem of your choice that supports xattrs is pretty much the only way to get full application compatibility.