Resolving SELinux Boot Error

SELinux (Security-Enhanced Linux) is the feature included in Linux that offers several security policies using LSM (Linux Security Modules) in Linux Kernel. In other words, it is the set of security modifications that you can apply to your Linux system. The policies applied allow you to set your system as per desired configuration. SELinux should not be misinterpreted as a different Linux distribution.

At times, you encounter errors with a SELinux using system preventing it from boot. Such behavior could occur due to file system inconsistencies. Thus, to resolve the issue, you might need to reformat the hard disk, which requires data restoration at a later stage. However, if you find that present data backup is not valid enough that it could give required results, it is recommended to immediately use advanced Linux Recovery applications.

As an example, while using your system, you receive an unexpected SELinux notification and the system hangs. Upon next restart, you encounter the similar eror message displaying on screen and the system fails to boot:

"SELinux: policydb magic number does not match the expected magic number