Pause or auto-snapshot on guest restart

[Galactic]

The Problem

There are some cases where it would be advantageous to automatically pause or take a snapshot of a guest that is in the process of restarting.

For example:

• Pausing during OS install to allow device removal, etc.
• Automatic snapshots during OS/software install as clean points to return to or clone.
• Pausing if there is an unexpected restart (to prevent restart loops, etc.)

Trying to do this manually often becomes a test of reflexes. It's necessary to catch the guest in the act of restarting, move focus to that window, and pause it before the guest OS takes over after restarting.

Implementation

Pausing would occur immediately after the restart (on the "Oracle" screen).

Taking snapshots would require converting the restart into a shutdown, taking an offline snapshot, and then starting the VM again.

For the GUI, I envision an "Action on Restart" menu item, and sub-items to pause during the next restart, or to take snapshots during the next 1-3 restarts (as the current operation may restart the guest multiple times). A CLI implementation of those options is straightforward enough as well.

In most cases, there would seem to be no need for this setting to be stored if the VM isn't running. However, the pause setting being sticky might be useful in cases such as the third example above.

[Frank Mehnert]

Right now it's at least possible to poweroff the VM on reset. This can be achieved by

VBoxManage setextradata VM_NAME "VBoxInternal2/TurnResetIntoPowerOff" 1