MacOS 15.2 Breaks the Ability to Create Bootable Startup Drive Backups

Dave Nanian, writing on the Shirt Pocket blog:

macOS 15.2 was released a few days ago, with a surprise. A terrible, awful surprise. Apple broke the replicator. Towards the end of replicating the Data volume, seemingly when it’s about to copy either Preboot or Recovery, it fails with a Resource Busy error.

In the past, Resource Busy could be worked around by ensuring the system was kept awake. But this new bug means, on most systems, there’s no fix. It just fails.

Since Apple took away the ability for 3rd parties (eg, us) to copy the OS, and took on the responsibility themselves, it’s been up to them to ensure this functionality continues to work. And in that, they’ve failed in macOS 15.2. Because this is their code, and we’re forced to rely on it to copy the OS, OS copying will not work until they fix it. [...]

For those who may be working for Apple, or have good contacts, the bug is FB16090831. A fix would be really helpful, folks.

This means Shirt Pocket’s outstanding utility SuperDuper can’t make a bootable clone of your startup drive on a machine running MacOS 15.2.0. It’s worth noting that you can still use SuperDuper (or other backup utilities) to clone all of your data, which is, by far, the most essential data in any backup. But bootable startup drives clones are an essential part of many people’s data integrity workflows.

This bug seems to affect CarbonCopyCloner and Apple’s own Time Machine, too. A bug like this is always unfortunate, but especially around the holidays, when it might take longer than usual to get fixed, even if the issue is escalated within Apple.

★ Wednesday, 18 December 2024