9 Advanced topics At least one of the above two commands will have to be provided if you have enabled the VirtualBox CoreDumper. Setting CoreDumpReplaceSystemDump sets up the VM to override the host’s core dumping mechanism and in the event of any crash only the VirtualBox CoreDumper would produce the core file. Setting CoreDumpLive sets up the VM to produce cores whenever the VM receives a SIGUSR2 signal. After producing the core file, the VM will not be terminated and will continue to run. You can then take cores of the VM process using: kill -s SIGUSR2 VM-process-id Core files produced by the VirtualBox CoreDumper are of the form core.vb.ProcessName.ProcessID, e.g.core.vb.VBoxHeadless.11321. 9.15 Locking down the VirtualBox manager GUI There are several advanced customization settings for locking down the VirtualBox manager, that is, removing some features that the user should not see. VBoxManage setextradata global GUI/Customizations OPTION[,OPTION...] where OPTION is one of the following keywords: noSelector Don’t allow to start the VirtualBox manager. Trying to do so will show a window containing a proper error message. noMenuBar VM windows will not contain a menu bar. noStatusBar VM windows will not contain a status bar. To disable any GUI customization do VBoxManage setextradata global GUI/Customizations To disable all host key combinations, open the preferences and change the host key to None. This might be useful when using VirtualBox in a kiosk mode. Furthermore, you can disallow certain actions when terminating a VM. To disallow specific actions, type: VBoxManage setextradata "VM name" GUI/RestrictedCloseActions OPTION[,OPTION...] where OPTION is one of the following keywords: SaveState Don’t allow the user to save the VM state when terminating the VM. Shutdown Don’t allow the user to shutdown the VM by sending the ACPI power-off event to the guest. PowerOff Don’t allow the user to power off the VM. Restore Don’t allow the user to return to the last snapshot when powering off the VM. Any combination of the above is allowed. If all options are specified, the VM cannot be shut down at all. 151