Hello James,

I am running into some issues. I own a new iMac 2017 with a 1TB fusion drive (FD) and MacOS Catalina running.
In case of a system crash on the iMac FD I would than change to a 1TB internal SSD rather than using again a FD. For this scenario
I need a backup strategy.

1)
Can I backup the FD completely on an external HFS+ disk?
I guess not cause Catalina system requires an AFPS volume and AFPS on spinning HDs is endlessly slow.
So maybe one possibility is to backup only the data/document folder onto an external HFS+ disk and in case of a a drive failure
do a catalina system install from another SSD with APFS where I installed the system backup with all programs etc.
including a Catalina install dmg. AFTER that I recover the document folder with Qrecall and the the archive on the external HFS disk.

FD 1T Backup plan:
--> external 1 SSD 128 GB /APFS with system, programs incl. Qrecall. plus Catalina installer
--> external 1 HDD 2TB /HFS+ with Qrecall archive with all document/Data files

In case of iMac system/FD crash:

A) Installing system from SSD to new imac 1TB SSD
B) Recovering the data with Qrecalll from the


2) Can I back up only the Catalina system with all the programs etc from the internal FD to an external SSD disk?

3)
Installing Catalina on the external SSD drive for backup the system with the same account name as you suggested earlier to prevent
ownership issues is problematic and leads to Apple ID problems because of the same names. I have to computers
registered with the same name under the same Apple ID....Apple gets confused.

What do you think?

Thanks a lot for your help in advance

Nico

Nico Dudek wrote:For this scenario
I need a backup strategy.

This is an excellent place to start.

Can I backup the FD completely on an external HFS+ disk?

With QRecall, yes!

QRecall chops up your files and stores that information in (essentially) a database. You're not actually storing the files or directories on the archive's volume, so the capabilities of the filesystem where the archive is written makes no difference. You can store APFS file on an HFS+ volume, HFS+ files on a Windows (FAT32) volume, ...

I guess not cause Catalina system requires an AFPS volume and AFPS on spinning HDs is endlessly slow.

Again, it doesn't matter. Also, APFS is much faster now. (In its early days, APFS was developed exclusively for SSDs and was not optimized for HDs, but that's in the past.) And going forwards, QRecall 3 will take advantage of APFS features for faster, and more reliable, archive updates.

So maybe one possibility is to backup only the data/document folder onto an external HFS+ disk and in case of a a drive failure
do a catalina system install from another SSD with APFS where I installed the system backup with all programs etc.

This is exactly what QRecall does now.

Starting in Catalina, your startup volume is actually two volumes. The system files are sequested on an immutable volume; a volume that cannot be modified, even by the kernel. The only[*] way to reinstall your operating system is to use the Apple macOS installer. When you capture your startup volume, QRecall find's its "data" volume (the secondary volume that you can write to) and captures everything there. The immutable system files are ignored.

To perform a whole-volume restore of a startup volume, you begin by formatting the volume and reinstalling the macOS (either via recovery mode or from an external startup drive -- I recommend creating a bootable USB drive for this purpose). Once installed, you can then use QRecall to restore the volume; QRecall will figure out that this is a startup volume, find the "data" half, and restore all of your files. Alternatively, you can then boot from the new system volume, reinstall QRecall, then use that to restore your files, but I prefer the former technique.

So here's my suggested preparation. Using either a handy external drive (which can also be the one your archive is stored on), or a bootable USB stick you keep around for emergencies:

Format the drive/stick APFS

Install a copy of Catalina

Reboot from the dirve/stick.

Download and install QRecall

Download and keep copy of the Catalina installer

When disaster strikes:

If replacing your drive, do the hardware swap.

Boot from the external drive/stick you created earlier.

Format your new startup drive and install macOS using Apple's installer.

Launch QRecall, open your archive, and restore the captured volume to the new one.

Reboot your new system and get back to work.

Does that make sense for you?

[*] Technically, you could restore the system files by booting from another volume and turning all of the safeties off, but I think that's a terrible idea and QRecall no longer supports this (without some hacking).

Hi James,

first of all thanks again for the always excellent and highly appreciated customer support!
Actually everything sounds logical. I resume:

1 Making an QRecal Archive of my running FD system onto my external 2TB backup partition on my HFS+ formatted 8TB disk

------ Crash on iMac -----

1 Hardware swap
2 Installing Catalina new from an earlier created USB Stick/External SSD (with Apple Catalina installer and Qrecall installed) onto the new 1TB new internal iMac disc (in my case it will be a SSD)
3 From the same USB Stick/External SSD I open Qrecall and open the Archive from the external 2TB HFS+ formatted drive and recover the files to the new replaced 1TB new internal iMac disc
4 Restart from the iMac again...

But one question by a non-developer stays:

Once installed, you can then use QRecall to restore the volume; QRecall will figure out that this is a startup volume, find the "data" half, and restore all of your files.

When I freshly install Catalina on my swapped iMac system HD it is blank without all my programs, that I had installed before. My question: are programs part of the Data so that they are in the found

"data" half

and will be restored than automatically to my system by Qrecall or are program files completely or partly belonging to the system half and I have to install them myself again later...? I hope the first is true

Thanks for your patience

Best Nico

Nico Dudek wrote:1 Hardware swap
2 Installing Catalina new from an earlier created USB Stick/External SSD (with Apple Catalina installer and Qrecall installed) onto the new 1TB new internal iMac disc (in my case it will be a SSD)
3 From the same USB Stick/External SSD I open Qrecall and open the Archive from the external 2TB HFS+ formatted drive and recover the files to the new replaced 1TB new internal iMac disc

I will also note that you can, if you like, flip steps 2 & 3. It's also permissible to format a brand new APFS volume, restore all of your files to it from the archive, and then install the operating system on top of that (this is actually the technique I use). The install will figure out that macOS has never been installed on this volume, split it, leaving all the files you previously restored on the "data" half of the system/data volume pair.

When I freshly install Catalina on my swapped iMac system HD it is blank without all my programs, that I had installed before. My question: are programs part of the Data so that they are in the found "data" half

Here's the only rule you need to remember: Everything that you, the system, or any other user, writes to your running system volumes resides on the "data" half of the system/data volume pair.

The whole point of having a "system" volume is that no process is allowed to write to it. Not even processes with super-user privileges. Not even the kernel. Once the macOS installer is finished, the "system" volume is frozen in amber until the next system update.

So if you installed something, it's on the "data" half of your startup volume pair. And it's that "data" volume that QRecall captures.

At run time, the operating system stitches the two together so it appears to be a single volume. This involves a lot of smoke and mirrors, and can seem pretty crazy at times?at least from the perspective of someone working at the filesystem level ... so almost no one.

As an example, in your Catalina /Applications folder you have many applications. Some were installed by Apple and some you installed yourself. If you use the low-level filesystem to ask what volume your copy of /Applications/Mail.app is on, it will tell you that package resides at /System/Applications/Mail.app. But if you ask it where /Applications/Photoshop.app resides, it will tell you that package is located at /System/Volumes/Data/Applications/Photoshop.app. So neither app is actually located at /Applications. Even stranger, you have a single folder (/Application) with items that reside on two different filesystems. Like I said, it's pretty crazy.

But the bottom line is that Mail is stored on the immutable "system" volume and cannot be modified/hacked, while Photoshop is on the "data" volume that you can alter and gets captured by QRecall.

Thanks a lot James! Learning always something new here