Apple released the final version of macOS 10.15.5 Catalina to all users on Tuesday evening publishedNow an angry developer has reported a bug that was already documented during the beta. Is this an unfortunate new feature after all?
In a new blog post, software developer Mike Bombich explained that bootable backups cannot be created using the CCC (Carbon Copy Cloner) backup tool under macOS 10.15.5 Catalina. The tricky thing is that no error message is displayed. The alleged bug was discovered during the beta phase and still not fixed by Apple. Now the question is, is this intentional? In his Contribution Bombich writes:
The chflags() system call can no longer set the SF_FIRMLINK flag on a folder on an APFS volume. Instead of failing with an error code, which we would have detected, it fails silently - it exits with a success exit status, but silently fails to set the special flag. This is a bug in the APFS file system implementation of chflags - when a system call doesn't do what you ask it to do, it should return an error code - not success.
We don't need to set many of these flags, nor do we need to set them often - only when backing up the macOS system volume for the first time. However, it is essential to the functionality of an APFS volume group, so failure to set these flags means that new full-system backups created from 10.15.5 onwards will be unbootable and it will appear as though none of your data is on the destination (to be clear, all data will be backed up though). Kind of the opposite of what we're trying to do here. It's hard to find kind words to express my feelings towards Apple at the moment.
Not a bug but intentional?
Bombich then went on to express his displeasure and explained that existing backups made under macOS 10.15.4 remain unaffected. This means that anyone who created a bootable backup before macOS 10.15.5 is not affected. This means that only those users who want to create such a backup under the new macOS version have a problem. But CCC has already taken precautions and provided users with a solution. So anyone running macOS 10.15.5 and want to create a new bootable backup using the well-known backup tool must download the CCC 5.1.18 beta. Finally, Bombich stated in his post that this is probably not a bug but an unannounced innovation, which is why he sharply criticizes Apple for this step. (Photo by alexey_boldin / Bigstockphoto)