


And snapshots cannot be changed, even by the system itself. For further security, these Macs also do not start directly from the system volume, but from a snapshot of the system. This seal is stored either in the T2 chip of the newer Intel Macs or in the Secure Enclave of the Apple M1/M2.Įach component of the system is signed in hierarchical order, and any change to a component would also invalidate the seal that represents the top level. Since macOS Big Sur, macOS has its home on its own volume, which is both read-only and cryptographically signed and sealed (referred to as a Sealed System Volume). In the past it was helpful to reinstall the system if you wanted to correct some Mac problems, but today this solution doesn’t make as much sense.
