When a host is removed from a cluster, the resources it provides are deducted from the total cluster resources. The virtual machines deployed on the host are either migrated to other hosts within the cluster, or remain with the host and are removed from the cluster, depending on the state of the virtual machines when the host is removed from the cluster.
You can remove hosts from a cluster by selecting them in the inventory and dragging them to a new location within the inventory. The new location can be a folder as a standalone host or another cluster.
Before you can remove a host from a cluster, you must power off all virtual machines that are running on the host, or migrate the virtual machines to a new host using vMotion.
- From the vSphere Client connected to a vCenter Server system, display the inventory.
- Right-click the appropriate managed host icon in the inventory panel, and select Enter Maintenance Mode from the pop-up menu.
If all virtual machines on the host are not powered off, the host will not enter maintenance mode.
If the host is inside a DRS-enabled cluster, entering maintenance mode causes DRS to attempt to automatically evacuate powered-on virtual machines from the host using vMotion.
- In the confirmation dialog that appears, click Yes.
The confirmation dialog also asks if you want to automatically evacuate virtual machines that are not powered on from the host. This is useful if you want those virtual machines to remain registered to a host within the cluster.
The host icon changes and the term “maintenance mode” is added to the name in parentheses.
- Select the host icon in the inventory panel, and drag it to the new location.
The host can be moved to another cluster or another datacenter. When the new location is selected, a blue box surrounds the cluster or datacenter name.
vCenter Server moves the host to the new location.
- Right-click the host, and select Exit Maintenance Mode from the pop-up menu.
- (Optional) Restart any virtual machines, as needed.