CloudStack provides administrators with complete control over the lifecycle of all guest VMs executing in the cloud. CloudStack provides several guest management operations for end users and administrators. VMs may be stopped, started, rebooted, and destroyed.

Guest VMs have a name and group. VM names and groups are opaque to CloudStack and are available for end users to organize their VMs. Each VM can have three names for use in different contexts. Only two of these names can be controlled by the user:

Guest VMs can be configured to be Highly Available (HA). An HA-enabled VM is monitored by the system. If the system detects that the VM is down, it will attempt to restart the VM, possibly on a different host. For more information, see HA-Enabled Virtual Machines on

Each new VM is allocated one public IP address. When the VM is started, CloudStack automatically creates a static NAT between this public IP address and the private IP address of the VM.

If elastic IP is in use (with the NetScaler load balancer), the IP address initially allocated to the new VM is not marked as elastic. The user must replace the automatically configured IP with a specifically acquired elastic IP, and set up the static NAT mapping between this new IP and the guest VM’s private IP. The VM’s original IP address is then released and returned to the pool of available public IPs.

CloudStack cannot distinguish a guest VM that was shut down by the user (such as with the “shutdown” command in Linux) from a VM that shut down unexpectedly. If an HA-enabled VM is shut down from inside the VM, CloudStack will restart it. To shut down an HA-enabled VM, you must go through the CloudStack UI or API.