282 Chapter11·HighAvailability:ResettoGood a virtualization host that the anti-affinity rule prevents from occurring, rather than bringing the virtual machine online it will stay offline in order to adhere to the anti-affinity rule. The ultimate question that needs to be asked is whether it is more important for a virtual machine to remain isolated or to be brought online in less than ideal circumstances. If the answer is that security is the most important aspect, then your high availability implementation may not provide the protection you expect in certain circumstances. If it is more important that the virtual machine be running, then high availability can accomplish the goal, but you will want to make sure that the virtual machine is migrated to a host in order to provide the required separation at the earliest available time. High availability is also frequently used to provide protection for virtual machines and resources by ensuring that the virtual machine remains operational as much as possible. While high availability can certainly help the overall security posture of an organization, it shouldn't be viewed as something to replace other defensive methods. If a virtual machine is compromised, all that high availability ensures is that the compromised virtual machine stays online and operational. You still need to imple-