A customer is running a VMware vSphere cluster in a business critical production environment.
Which step should be performed before servicing an HP server blade?

A.
Place the host that needs to be serviced in Maintenance mode

B.
Power off the server blade before removing it from the enclosure

C.
Power off all virtual machines in the environment

D.
Suspend the virtual machines on the host that needs to be serviced

Explanation:

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Place a Host in Maintenance Mode
You place a host in maintenance mode when you need to service it, for example, to install more
memory. A host enters or leaves maintenance mode only as the result of a user request.
Virtual machines that are running on a host entering maintenance mode need to be migrated to
another host (either manually or automatically by DRS) or shut down. The host is in a state of
Entering Maintenance Mode until all running virtual machines are powered down or migrated to
different hosts. You cannot power on virtual machines or migrate virtual machines to a host
entering maintenance mode.
When no more running virtual machines are on the host, the host’s icon changes to include under
maintenance and the host’s Summary panel indicates the new state. While in maintenance mode,
the host does not allow you to deploy or power on a virtual machine.
Note

DRS does not recommend (or perform, in fully automated mode) any virtual machine migrations
off of a host entering maintenance or standby mode if the vSphere HA failover level would be
violated after the host enters the requested mode.
Procedure
1
In the vSphere Client inventory, right-click a host and select Enter Maintenance Mode.
If the host is part of a partially automated or manual DRS cluster, a list of migration
recommendations for virtual machines running on the host appears.
If the host is part of an automated DRS cluster, virtual machines are migrated to different hosts
when the host enters maintenance mode.
2
If applicable, click Apply Recommendations.
The host is in maintenance mode until you select Exit Maintenance Mode