I can’t solve the problem but it is most likely related to the fact that Fedora is not Debian based like Ubuntu is. I hope there is a way to span these distros. Hopefully, someone on here might be able to answer this. @kernellinux (Noah) may have some insight. If not response works out here, post a question over at podcast.asknoahshow.com
Here is a graphic that shows the relationships between all of the distros that have been developed.
If I’m understanding this correctly, You are wanting to restore an snapshot of a previous install? (You had Fedora 34, went to Ubuntu, come back to Fedora 34 wanting to restore a snapshot from the first install you had…)
I’m not too familiar with BTRFS which is what I will “assume” you were using for all your previous installs, but Snapshots of a partition are not Backups per-say of the install. A Snapshot is “a place in time to allow you to revert back” Like rollback feature.
Here’s the thing, Because your snapshots are from different installs of an OS, your Drive Partitions are different and the UUID is different as well. Amongst other things.
I guess what i am trying to say is that a Snapshot is not a Backup in the most explicit sense.
Here is an example:
I run an LVM with my partitions as XFS. Prior to doing a full system install (Nuke and Pave) I use XFS Dump to basically clone my file system, then on my new install I use XFS restore to gain everything back.
If on my working machine and an dnf update breaks my machine I can use LVM Snapshot to roll back the machine to a safe point in time. These two things are not the same. I can’t take a snapshot of my system then drop it in on a fresh install to restore my snapshot.
The reason being:
Snapshots are basically a collection of metadata about your current partition layout + free space+file system. A new install will not have any information in relation to that metadata because the partition and file system has changed. A Backup, is like a clone, image of your files that can be restored. A true system backup is best handled by the file system itself. A user can back up personal files on to external media, but a clone, or system backup can be better handled by the file system because of features in place to do so. (like xfsdump , xfsrestore , btrfs subvolume snapshot , btrbk )
This is not a Distribution issue, Snapshots and backups are distro agnostic handled by the Volume manager (BTRFS, LVM etc.) . I perceive the problem to be a mismatch in partition and file system. Even if the same Volume manager was used (BTRFS) this does not mean a snapshot is portable. A Backup of the system on the other hand, is !
@VE64RD correct me if I am wrong, but does Timeshift have a way to make a backup? I know it’s common use is for snapshots… Some times these features are more geared towards direct interaction with the Volume manager than a GUI app.
In the hopes that @MichaelTunnell@dasgeek@kernellinux see this post, It would be a great show idea ( and save me an email ) to discuss the differences with Snapshots vs Backups, since the term is not interchangeable but is commonly used to reference a similar action. ( Shadow Copy included )
You can have a look in Timeshift and what you set there. Fedora now uses btrfs by default and Ubuntu ext4 as files systems. Now in Timeshift you can decide to use either rsync or btrfs but for btrfs you need that running as your file system. That could then of course lead to incompatibilities.
As for backup software there is choice out there. Here some tips from our community:
I would go all in on the file system tools. Its the way it should be done. If you are on Fedora, the current default install is BTRFS, a quick RTM or Timeshift will set up your back ups going and possibly get you to a point where you schedule back ups as you update the system. If you are on LVM/XFS , well you have LVM’s snapshot lvcreate feature and XFS’s xfsdump , xfsrestore for full system backups.
It looks like you are already comfortable with Timeshift and BTRFS with Fedora, sounds like the way to go !
side note:dnf history can help you rollback an update if one wrecks your system for some strange reason. . .