The hype cycle in tech is legendary, but virtualization is one trend with proven relevance for the Oracle RAC DBA. Knowing how to deploy, manage and optimize performance of Oracle RAC in a virtualized environment will make you a highly valued employee, and you ignore this trend at your peril. In this article, I’ll summarize a few key things you should know.
Everyone’s virtualizing, even Oracle RAC
Some estimate that as much as 73% of all workloads have already been virtualized, and it’s increasingly common to virtualize business-critical workloads like Oracle RAC. Despite initial reluctance, Oracle did issue a policy supporting Oracle RAC on VMware. So, for Oracle RAC DBAs, the writing is on the wall: if your data server hasn’t been virtualized yet, it likely will be soon. The question for DBAs now is, “How can I make sure that I get the most from virtualizing Oracle RAC?”
Learn everything you can about virtualization
First, learn as much as you can about virtualization. Take your virtualization administrators to lunch and pick their brains. Understand your organization’s virtualization strategy and architecture. It pays to develop a solid partnership with these guys. There are also great resources available from Oracle’s IOUG Virtualization Group (http://www.ioug.org/virtualization)
Become an expert on using VMware DRS, HA and vMotion
If your shop is like 67% of shops virtualizing, you’re using VMware, and you should become familiar with how VMware can make your life as an Oracle RAC DBA easier. One of the most powerful features of VMware is vMotion, a live migration tool that lets you migrate a virtual machine (VM) from, say, a failing physical host, without any downtime or performance hits. You can get a new instance of RAC up within minutes instead of the days and even weeks you might be used to. VMware’s DRS Host Affinity rules let you load balance and control licensing costs by restricting movement of VMs between a subset of hosts within a cluster. VMware High Availability (HA) gives you more cost-effective availability than you can typically get with failover solutions that are tied to an operating system or specific applications.
Develop a virtualization plan for Oracle RAC
Develop a virtualization plan for your team. You can start by running test workloads on a VM. Next, run some development and staging workloads. You’ll probably find that running a database server on a VM will require some changes to existing processes. Document the issues that you find and any differences you see. Pay attention to the interaction between what happens in the physical and VM layers and Oracle RAC. Educate the rest of your team about what you’re finding and the changes you’ll need to make.
Get visibility across the physical, virtual and database layers
Based on our experience, both here in our own lab and with our clients, it’s clear that you’ll need access to tools that clearly show you what is happening in the database, virtual and physical layers so you can accurately pinpoint problems and develop a plan to resolve them. You may be able to get by with access to the tools the virtual administrators use, but you’re likely to spend a lot more time analyzing and correlating information. SolarWinds DPA is one tool that can give you the visibility you’ll need.
Virtualization can make you a better DBA
Armed with knowledge about virtualization and with the right tools, you will become a more skilled and more valuable DBA. And you will help your organization ensure that running Oracle RAC on a virtual machine delivers all the benefits expected of virtualization without impacting all the critical capabilities of Oracle RAC.