Backdoor ways to reboot a Windows server ;).
When you need to reboot a Windows server, you’ll occasionally encounter obstacles to making that happen. For instance, if remote desktop services aren’t working, how can you reboot the server? Here is a list of tricks I’ve collected over the years for rebooting or shutting down a system when I can’t simply go to the Start Menu in Windows.
- The shutdown.exe command: This gem will send a remote (or local) shutdown command to a system. Entering shutdown /r /m \\servername /f /t 10 will send a remote reboot to a system. Shutdown.exe is current on all modern Windows systems; in older versions, it was located on the Resource Kit. For more details, read this Microsoft KB article on the shutdown.exe command.
- PowerShell Restart-Computer: The equivalent of the command above in PowerShell is:
Restart-Computer -Force -ComputerName SERVERNAME
- Hardware management device: If a device such as an HP iLO or Dell DRAC is in use, there is a virtual power button and remote screen console tool to show the system’s state regardless of the state of the operating system. If these devices are not configured with new servers, it’s a good idea to have them configured in case the mechanisms within the operating system are not available.
- Virtual machine power button: If the system in question is a virtual machine, all hypervisors have a virtual power button to reset the system. In VMware vSphere, be sure to select the option to Shut Down The Guest Operating System instead of the Power Off; this will make the call to VMware Tools to make it a clean shutdown. If that fails, the Power Off button will be the next logical step.
- Console walkthrough: In the situation where the server administrator does not have physical access to the system, walking someone through the process may be effective. For security reasons, basically a single user (domain or locally) can be created with the sole permission of rebooting the server. That person could log on as this temporary user, and then it is immediately destroyed after the local shutdown command is issued. Further, that temporary user could be created with a profile to run the reboot script on their logon to not have any interaction by the person assisting the server administrator.
- Configure a scheduled task through Group Policy: If you can’t access the system in any other mainstream way — perhaps the Windows Firewall is turned on and you can’t get in to turn it off — set a GPO to reconfigure the firewall state and slip in a reboot command in the form of the shutdown.exe command executing locally (removing the /m parameter from above). The hard part will be getting the GPO to deploy quickly.
- Enterprise system management packages: Packages such as Symantec’s Altiris and Microsoft System Center agents communicate to the management server and can receive a command to reboot the server.
- Pull the plug: This is definitely not an ideal approach, but it is effective. For physical servers, if a managed power strip with port control is available, a single system can have its power removed and restored.
Who said? Rick Vanover said ;).