Question: How to clone an APFS system disk with Disk Utility.
It's been now a while I've been doing tests with High Sierra (10.13.5 recently). And I still can't envision moving to it with an SSD system disk, as I haven't yet been able to figure a way to clone an APFS system disk with Disk Utility.
Using Disk Utility to clone an APFS data disk works fine, without any issue. But when trying to clone an APFS system disk, the works progresses smoothly until the last step. Then, the target volume inversion fails (by the way, what on Earth is this "target volume inversion" and what is it needed for?). DU informs me that "APFS inverter failed to invert the volume - Invalid argument" and then "OSStatus error 22". Then I'm left with a useless target volume, only good to be reformatted. For information, the target disk is a newly created APFS partition on an external Thunderbolt/USB3 rotational disk (most of the other partitions on this disk are still HFS+), if this is relevant to the issue.
There's no way I'm ready to do production work on a system where I can't clone the system disk and obtain a verified bootable copy of my system as a fallback system disk in case of a problem with the internal disk.
So the question is: "How can one clone an APFS system disk with DU and obtain a bootable clone"?
I'm aware that some third party backup softwares say they can create such a clone (I do have CCC V5, but haven't yet tested this feature with APFS system disks, it's still on my "to do" list), but even CCC does not perform a complete "Verify" pass on its target volume. At best, when told to, it verifies checksums on previously saved files, which, while good, is still not enough.
MacBook Pro, macOS High Sierra (10.13.5), 8 GB Memory