At VMworld during one of my group discussions there was a discussion around using vSphere HA or vCenter Heartbeat to protect the vCenter Server. Coincidentally it is something that we recently discussed internally on Socialcast and I figured I would give my thoughts on this topic. My answer was short and simple: It depends.
Yes I bet some of you saw that coming… But let me elaborate. vCenter availability is crucial in my opinion when it comes to operating your environment. However your environment is not about vSphere. Your environment is not really about virtual machines. Your environment is about the services that you offer!
Your service level agreement typically is based on up-time of the service, makes sense right. No one really cares about the management platform, well I do and you do but your customers probably do not. Your customers care about the availability of their service.
Will their service have an interruption when vCenter is down is the question you will need to ask yourself. In most cases the answer will probably be no, and in those cases you will need to ask yourself what the downtime is you can afford from a management perspective. Is a minute or two okay? Than vSphere HA can help you and there is no need for Heartbeat or other complex clustering solutions. If a couple of minutes is not acceptable than Heartbeat is an option.
If there is a service interruption for the customer when vCenter is down (for instance in a test / dev cloud where provisioning processes are key, vCloud Director, View) you should consider using vCenter Heartbeat. Again, it all depends on your service level agreement. In some cases vCenter availability is crucial, in other cases a downtime of minutes is within the defined boundaries. The answer remains, it depends… it depends on your use case and service level agreement.
