How to Place a Host in Maintenance Mode in VMM
Updated: May 13, 2016
Applies To: System Center 2012 SP1 - Virtual Machine Manager, System Center 2012 R2 Virtual Machine Manager, System Center 2012 - Virtual Machine Manager
In Virtual Machine Manager (VMM), you can start maintenance mode for a virtual machine host whenever you need to perform maintenance tasks on the physical host, such as applying security updates or replacing hardware on the physical host computer. You can place Hyper-V hosts, VMware ESX hosts, and Citrix XenServer hosts that are managed by VMM into maintenance mode.
When you start maintenance mode on a host, you can do one of the following:
Place all running virtual machines into a saved state.
On a host cluster that is capable of live migration (including Citrix XenMotion and VMware vMotion), move all highly available virtual machines to other hosts in the cluster.
Warning
Placing a running virtual machine in a saved state causes a loss of service to any users of that virtual machine.
Note
For ESX hosts, if the VMware Distributed Resources Scheduler is not configured, all virtual machines on the host must be either manually shut down or moved to another host to successfully start maintenance mode on an ESX host.
When a host is in maintenance mode, the following restrictions are placed on the host:
Virtual machines cannot be created on the host.
Virtual machines cannot be moved to the host.
The host has a zero rating and cannot be selected for placement.
The host is excluded from Dynamic Optimization.
Note
If VMM is integrated with Operations Manager, when a host is placed in maintenance mode in VMM, Operations Manager also places the host into maintenance mode. In maintenance mode, the Operations Manager agent suppresses alerts, notifications, rules, monitors, automatic responses, state changes, and new alerts.
To start maintenance mode on a host
In the VMM console, open the Fabric workspace.
On the Home tab, in the Show group, click Fabric Resources.
In the Fabric pane, expand Servers, and then expand All Hosts.
In the Hosts pane, locate and then click the host that you want to place in maintenance mode.
On the Host tab, in the Host group, click Start Maintenance Mode.
In the Start Maintenance Mode dialog box, select either of the following, and then click OK.
Move all virtual machines to other hosts in the cluster
Place all running virtual machines into a saved state.
Tip
When a host is in maintenance mode, the Host Status for the host displays as In Maintenance Mode in the Hosts pane in the Fabric workspace.
To stop maintenance mode on a host
In the VMM console, open the Fabric workspace.
On the Home tab, in the Show group, click Fabric Resources.
In the Fabric pane, expand Servers, and then expand All Hosts.
In the Hosts pane, locate and then click the host that you want to bring out of maintenance mode.
On the Host tab, in the Host group, click Stop Maintenance Mode.
Important
When you bring a host out of maintenance mode, VMM does not automatically restart the virtual machines and does not automatically move any migrated virtual machines back on to the host.