VMware and Microsoft and Citrix . . .

The management industry in general has embraced platform-agnostic monitoring, but mostly for the physical world. If an enterprise uses VMware plus virtualization technologies from IBM, Microsoft and Sun, it's going to need virtualization-management tools from VMware, IBM, Microsoft and Sun as well.

"The reality is, no management vendor does it all yet," says Andi Mann, research director with Enterprise Management Associates, noting that CA is out in front.

Management-software makers typically don't add support for multiple platforms until customers demand it, and with VMware dominating enterprise production servers, the majority of commercial management tools focus on that environment, industry watchers say. Microsoft, however, followed its entry into the hypervisor market with news around heterogeneous virtual-server-management software, dubbed Virtual Machine Manager. In addition, such third-party software vendors as eG Innovations are beginning to add support for multiple virtual-server environments. Start-ups such as Fortisphere are building their new businesses on the value proposition that their technology can manage across virtual platforms.

"When Microsoft Hyper-V and Citrix XenServer are in production, established management vendors will start to recognize heterogeneity as part of a requirement, and that is mandatory for any start-up in the market, too," says Stephen Elliot, research director for IDC's enterprise systems. "But the bigger picture, and further complicating things beyond multiple server platforms, will be storage, desktop or other virtualization implementations. Again, you won't see the management vendors take this on until the technologies are in production environments."

Out of the silo, into the fire

The first group to experience the challenges will be enterprise IT managers who virtualize their storage along with server resources. To optimize such a virtualized environment, they would need management software that can spot when storage is at the root of server performance problems.

"With multiple layers, virtualization can obfuscate the real sources of a problem," says Jonathan Bryce, co-founder of Mosso, a Rackspace US company that provides cloud hosting and services.

Mosso has hundreds of multicore, multiprocessor HP servers and VMware virtual servers in production - and other hypervisors in various test environments - plus virtual disks running on Network Appliance storage. The virtual disks connect to a specific set of network interface cards on the back-end HP servers. The network and storage is all shared, Bryce says.

Bryce recalls an incident in which a Linux server running virtual machines started to perform very slowly and experience a high load and increased traffic. "It took us days to figure out we had overrun the I/O limits on the back-end storage and . . . that that had manifested into a slow-running Linux server," he says.

Using Hyperic HQ software, he can see into the storage level of his virtual environment and understand which servers are slow, how the I/O is performing and whether physical hosts are on target, Bryce says. "Hyperic doesn't help eliminate server sprawl, but it gives us a view into the layers of the environment, which in the past made performance diagnosis so much more difficult."