It's a big step in the right direction, according to IT pros. But while it brings RAC into line with Oracle's existing VMware support policy for Oracle databases, it goes no further, meaning Oracle still isn't quite agnostic to which server virtualisation platform its users choose. The support statement includes the following:
Oracle has not certified any of its products on VMware virtualised environments. Oracle Support will assist customers running Oracle products on VMware in the following manner: Oracle will only provide support for issues that either are known to occur on the native OS, or can be demonstrated not to be as a result of running on VMware.
The fact that RAC is no longer a special exception shows at least a slight thaw in Oracle's stance toward VMware. But support policies aren't the chief factor in users' decisions about whether and how to virtualise Oracle.
Obstacles to Oracle virtualisation
Regardless of how Oracle's stance toward VMware changes from here, users have largely made up their minds about whether to run Oracle apps on separate Oracle VM environments or on VMware. But the choice of hypervisor platform is only one of the factors users must consider when evaluating whether to virtualise Oracle applications and databases.
Some users have cited limitations on VMware's side as the reason they shy away from virtualising Oracle's RAC, rather than the fact that Oracle had given RAC on VMware the cold shoulder.
VMware doesn't support the vMotion of virtual machines (VMs) attached to a RAC cluster's shared SCSI bus in Raw Device Mapping (RDM) mode. So, if a physical RAC server is put into maintenance mode, the user can't move its Oracle VMs to another RAC cluster node without shutting them down, which can violate some production service-level agreements in mission-critical environments.
Others point out that there are also licensing regulations to consider before running Oracle on vSphere, regardless of support or technical issues.
Oracle Enterprise Edition, for example, still has a per-processor licensing scheme, despite a general move by software makers toward per-socket or per-vCPU licensing policies to accommodate virtualisation, said Brady Reiter, general manager of enterprise architecture and application strategy for Navisite Inc., a managed hosting and application services provider based in Andover, Mass.
There is an exception to this for 'hard partitions' like Sun's containers or Oracle VM, Reiter said, "but VMware isn't a hard partition, and you have to license anything that VM can touch. You can limit where the VM resides, but in some ways that can defeat the purpose of virtualisation."
Nevertheless, the change in support for RAC is "a step in the right direction," Reiter said. "The change in the support agreement will change our plans," he said. "Now if a customer comes to us and wants to run RAC in our cloud environment, we can let them do that." Ultimately though, "I'd love to see a licensing model that works with virtualisation technologies other than their own."
Whittling away Oracle costs
Some users are avoiding the complexities that make virtualising tier-one applications like databases a delicate endeavor, regardless of virtualisation platform. At the same time, they are beginning to investigate virtualising other components of the Oracle environment.
One such user, Chris Rima, an infrastructure supervisor with a utility, is running Oracle applications on Sun SPARC-based hardware, meaning he's close to running Oracle's ideal soup-to-nuts stack -- the missing component being Oracle VM.
Rima said he is moving cautiously toward virtualising Oracle's middleware and management software layers over the course of the next year, but that virtualisation will be attempted using vSphere, which he already uses for other apps in his shop.
For Rima, the decision to virtualise Oracle apps using vSphere is mainly a matter of cutting hardware and operational costs, by running only the most mission-critical portions of the software on Sun's proprietary SPARC processors and moving as many of the rest as possible to commodity x86 hardware.
"Our core expertise with Oracle database is on SPARC," Rima said. "But for less mission-critical things than the database, we're looking for cost savings with x86 hardware…and we don't have the full time engineers internally to support two hypervisor environments."
Beth Pariseau is a senior news writer for SearchServerVirtualization.com. Write to her at firstname.lastname@example.org.