@Armanator That depends upon when you were trying to reboot and after doing what configurations. For example you might have done everything right and rebooted fine to check the persistency of the configurations except the last configuration and you did not check it then.
Before grading, the systems are simply rebooted and if they are not coming up - then surely somewhere the VM/ VMs were misconfigured.
To avoid this you can do three things :
1. Carefully work on the persistent configurations of each task and verify everything such as result of the configuration, the configuraiton files , the services etc which is required for persistency and at last you reboot and reverify your tasks results - which will verify all configurations of all tasks of that VM.
2. Reboot after each task of persistent configuration - to verify if it persists reboot. But this is time taking and can affect your overall exam if you did not manage to troubleshoot properly and work fast and perform all the tasks in time.
3. Follow step 1 but reboot in between (for example after doing major configurations)
I personally favor the first method but it all depends upon your level of expertise and practice.
