At the risk of sounding like a public service announcement, this week’s post comes with a health warning: read the small print when choosing your virtual availability provider.

Finding a fault tolerant virtualization solution to guarantee availability of your critical applications can be rather like choosing whether to die by the knife or by the sword.

Of course, at Stratus, we’d prefer that you did not choose to die at all. We’d prefer that you choose to live. This post aims to help you do just that…

So what’s the deal?

Every availability solution has its strengths and limitations. In the case of virtualized availability the considerations are

1.    Actual fault tolerance Vs claimed fault tolerance
2.    Operational simplicity
3.    Performance and financial advantages

Here are some key questions for vendors:

• How scalable is the solution?
• Is it restricted to one core?
• If so, how many systems need to be available to ensure continuous availability?
• What impact does this have on costs?
• What impact does this have on latency?

It’s also worth investigating the benefits of fault tolerance versus clustering. Clustering solutions, such as VMware HA, can scale but introduce additional complexity and do not protect against data loss.

As VMware states when describing its VMware FT:

“This is different from HA, which restarts any virtual machines that fail. Such a restart requires the virtual machines to complete the process of rebooting, and information about the state of the virtual machine, such as applications or unsaved user-entered information, might be lost”

VMware FT may be different from VMware HA but it is still a clustering solution. It still requires separate physical servers. It still does not scale beyond a single core. It still incurs additional overhead as a function of its architecture

Sure, there is no “best”, “one size fits all”  solution for virtualized availability and there are situations where one virtualized availability solution is better suited than another, yet Stratus FT Server is always worth considering. It guarantees:

• Industry leading fault tolerance
• Operational simplicity
• Absolute security
• Total scalability
• No hidden costs