Thank you for your response. To clarify: I am not asking about backups proper (though I appreciate the suggestions). My only question is how to make a copy of the crypto metadata.
On 2023-01-03, Nathan Carruth <n.carr...@alum.utoronto.ca> wrote: > I am with you 100% on backups. My real question was, How > does one backup crypto volume metadata? Given that > it can be backed up, clearly it should be, but there is no > information in any of the cited documentation as to where > the metadata is or how to back it up. There doesn't seem to be much point in backing up *just* the metadata, how will that help you get data back? I think your options to backup the encrypted data are: - backup from the mounted filesystem using some backup tool that has a way to encrypt. There's a wide choice of backup software, including borg and restic, that do this in a nice way, that will also allow cross-OS restores if needed, restoring individual files, etc. You can also use e.g. dump or tar, piping the output through an encryption tool before storing. - backup the whole disk partition/s e.g. with dd. This might be a bit impractical as to keep things consistent I think you'll want to unmount, detach the softraid device, backup, reattach, remount. Restoration is much more fiddly too. Additionally this isn't designed as an archival format; it would seem that it will be much more fragile.
