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A vSphere 5.5 Gem: Application High Availability

In our continued coverage of VMworld 2013 and vSphere 5.5, let me highlight a feature that has not been in the limelight as much as we might think. That feature is application high availability. Ask any VMware administrator the first feature they'd configure I am willing to bet it would be HA. HA allows the vSphere platform to monitor virtual machines and in the event that a "heartbeat" is not detected by VMware Tools or if I/O activity is not detected, the platform deems the VM as a failed one and attempts to restart it on an alternative host.

Application high availability builds on this stellar technology and elevates its effectiveness to the application layer. Yes, it can monitor line of business applications such as Microsoft SQL Server and Exchange, apps from Oracle and others. App HA will monitor application services and attempt to restart these services should they fail. It can also restart the entire VM in the event that the services were unsuccessfully restarted. This is a very simplified summary of the capabilities of App HA, but it is a lot more extensive than I can cover in a short time.

From an architectural stand point, deploying App HA is relatively straightforward, especially at this stage of the game where most environments will leverage this in a light way. App HA comes in the form of a virtual appliance and can be deployed just like any other appliance. Its primary responsibility is to store and manage App HA policies. App HA requires VMware vFabric Hyperic, which also comes in the form of a virtual appliance -- it's responsible for monitoring applications and enforces App HA policies. In a nutshell, in order to deploy and take advantage of VMware App HA you will need two virtual appliances, the App HA appliance and the vFabric Hyperic appliance.

App HA isn't really a new feature, as it was first released with vSphere 5.0. So, if this feature existed in vSphere 5.0, why all the hype now? When it was introduced, its use was narrowly focused and required some development work in order to leverage it. That, or you had to use third-party software like Symantec Application Monitoring, which leveraged the API of App HA API. Conversely, in-house developers could also leverage the VMware vSphere Guest SDK to plug in their custom applications and leverage App HA.

Now, with vSphere 5.5 VMware is offering App HA with monitoring for popular line of business applications right out of the box. That means you no longer need the third-party software crutch, assuming all your apps are covered with native App HA. It's definitely a welcome change.

I am interested to from you if you plan to use App HA -- the where, how, when and what. Please share in the comments here.

Posted by Elias Khnaser on 09/09/2013 at 3:53 PM


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