Hosts can be removed from the cloud as needed. The procedure to remove a host depends on the hypervisor type.
11.4.1. Removing XenServer and KVM Hosts
A node cannot be removed from a cluster until it has been placed in maintenance mode. This will ensure that all of the VMs on it have been migrated to other Hosts. To remove a Host from the cloud:
Then you may power down the Host, re-use its IP address, re-install it, etc
11.4.2. Removing vSphere Hosts
To remove this type of host, first place it in maintenance mode, as described in Section 11.2, “Scheduled Maintenance and Maintenance Mode for Hosts”. Then use CloudStack to remove the host. CloudStack will not direct commands to a host that has been removed using CloudStack. However, the host may still exist in the vCenter cluster.
