Most IT teams get to 60% virtualization and stop when they hit tier-one and proprietary applications. With VMware vSphere's advanced features and the minimal performance impact of virtualization, sometimes all you need to win over these last holdouts is a clear message, said Chris Ward, GreenPages CTO, presenting at a 2013 New England VTUG meeting.
"Critical apps such as Oracle [Database] and [Microsoft SharePoint] are often left un-virtualized, along with an organization's proprietary apps in healthcare and other industries," said Ward. These applications' owners are leery of the performance hit from virtualization, the political wrangling that could occur when an app shares resources and support in the IT infrastructure and how their licensing requirements would change.
But if your IT infrastructure mixes virtualized and physical, the return on investment that virtualization promises could be washed away in multiple management tools and support and licensing costs.
Virtualization isn't really about hardware consolidation anymore, Ward said. But the IT team is spending twice as much time and budget on high availability (
The technical case for virtualizing critical apps
VMware vSphere's management options and clustering technology are better than Microsoft Hyper-V's for tier-one apps, Ward said, though "everyone is taking a look at Hyper-V." He acknowledges that the upfront spending on VMware virtualization is a harder sell for small organizations -- "A SAN [storage-area network] costs $20,000 to $30,000 just to talk about it" -- but expects VMware to release virtual SAN features with the next edition of vSphere. While memory overcommit can be a selling point for vSphere over Hyper-V, in Ward's experience, the low cost of memory means that few vSphere users overcommit memory today.
Virtualization offers dynamic scaling for business-critical applications, so IT can start an app off with abundant resources and only scale back what isn't needed, as well as adding resources and servers quickly. Business-critical app management can get simpler, since HA and DR go from a mess of individualized systems to a uniform virtual method, getting rid of what Ward calls a "management nightmare." In some cases, database virtualization will reduce licensing costs. If a critical app is bound to outdated hardware, virtualizing it can also include re-platforming to a standard x86 blade server. Re-platforming -- where the app is rewritten to work on newer hardware -- will often improve performance and save money, Ward said.
But performance is often a concern. Does a virtualized application perform as well as a physical app? No, Ward said, it never does, but that the simple answer doesn't tell the full story. Rarely will the roughly 0.5 to 3.0% reduction in CPU speed be noticeable enough to justify the overhead that goes into keeping an app physical. If it is, there's "a solid case" for leaving the app alone, Ward noted. Even apps that are the only virtual machine on a host are worth virtualizing for the high-availability and licensing benefits. Skipping the physical-to-virtual conversion and building the app fresh as a virtual machine will give you a chance to clear out old bugs and workarounds (what Ward sums up as "ancient junk"), and maybe even upgrade to a new operating system.
How to get business-critical apps virtualized, on the non-technical side
There are other factors involved in virtualizing those mission-critical apps, and they’re mostly cultural. Try some of these tactics for easing the path, Ward said.
- Get the application's owners and users involved. Host a happy hour or find other creative means to communicate with people that might resist the change. Try sending a letter about virtualization to stakeholders.
- Find someone outside of IT to sponsor the initiative. Get an executive excited about the plan.
- Draw up a design that considers the cost and performance metrics for the app.
- Use metrics to create chargeback numbers, showing the benefit that they'll get from virtualization.
This was first published in June 2013