information may not be invalid. Additionally, after the user exits the runcmd environment, the process becomes an unterminated process. (See 3.2 Unterminated Process for more details.)

3.2 Unterminated Process

A process that is started in the runcmd environment and remains active after drd runcmd completes is not DRD-safe because it is using data from the inactive system image, but is now running in the booted system image. Processes that are not associated with a user terminal (for example, tty), such as a daemon that is started in a control script from within the runcmd environment, will remain active even after the user exits the runcmd environment. The unmount of the inactive system image at the end of drd runcmd processing—or in response to any subsequent drd unmount command—will fail because the process is still running, making the root file system of the inactive system image busy.

The following example is an illustration of an unsafe action related to an unterminated process.

Example 3.2.1 – Illegal Persistence: A process started in the runcmd environment continues to execute after the shell exits. Upon request from a process started in the booted system image, the persistent process will return information from the inactive system image. For example, if the inactive system image is running version 2 of a software application and the booted system image is running version 1, the persistent process will respond on the running system with version 2 information.