INSTABILITY IN EX200v8 VMs - STUCK IN EMERGENCY MODE
Issue : Virtual Machines that are used in EX200v8 Exam are unstable and sometimes get stuck in emergency mode. Pressing Ctrl+D, Entering Password or Rebooting doesn't solve the issue.
You are in emergency mode. After logging in, type "journalctl -xb" to view system logs, "systemctl reboot" to reboot, "systemctl default" or "exit" to boot into default mode.
Give root password for maintenance
(or press Control-D to continue):
(See attached image)
Re-creation : It seems the instability is triggerred by a sequence on VM machines used in EX200 exam. This issue does not occur with normal Red Hat release. Sequence is (1)Interrupt Boot Process, (2)Remove "rhgb quiet", put "rd.break enforcing=0" and press "ctrl+x", (3)remount sysroot as readwrite using "mount -o remount,rw /sysroot", change to sysroot "chroot /sysroot" (4)change password using "passwd" and (5)relabel using "touch /.autorelabel". (6)Configure a partition and a VDO drive.
Machines with Fault that I found:
Red Hat Enterprise Linux 8.0 (Oopta)
Kernel 4.18.0-80.e18.x86_64 on an x86_64
Running on Oracle Virtual Box 7.0
Machines that work without the issue:
Red Hat Enterprise Linux 8.8 (Oopta)
Kernel 4.18.0-477.10.1.e18_8.x86_64 on an x86_64
Running on VMWare Workstation Pro 16
Comment: I only practiced using the latest version ISO that can be downloaded from Red Hat website and this did not have that issue. Unfortunately, I only understood this sequence introduces an instability to the machine after I sat for the EX200 exam. This caused the automatic marking script to completely ignore the solutions completed in node2, and I failed the exam scoring 150/300. I have also opened a comment about this issue and am waiting for a reply. Also speculated that the instability occurs because the VDO drive can't be relabelled by the system.
Avoidance: Avoiding specifically declaring "enforcing=0" might help avoid the issue, but its not understanble why this may cause the issues, as autorelabel anyway configures system as enforcing=0.
Solutions: Once the issue occur, the solution is not clear. We can boot into emergency mode but this doesn't seem to help anyway. I assume some changes in grub configs should do the trick, but I am not at that level yet.
