Virtual Servers Challenge Storage Managers

As businesses increase their deployment of virtual servers and virtual data center infrastructure, storage managers are facing new challenges. Those include planning for future capacity, monitoring storage utilization, allocating storage, backing up or replicating data, and migrating data stores, according to a survey of virtual server administrators released this week by storage vendor Xiotech Corp.

The company asked 185 virtual server administrators a variety of questions about building and managing virtual infrastructures. They said their top challenges when it comes to managing software and storage were future capacity planning (32 percent), monitoring storage utilization (28 percent), allocating storage (20 percent), backing up or replicating virtual server storage (17 percent), and migrating data stores from one tier of disk to another(3 percent).

"As users load more virtual machines, run more applications, and serve more users on each physical server, monitoring storage usage levels and planning capacity are crucial, said Mark Peters, an analyst with Enterprise Strategy Group, in a statement. "Our research shows that many users experience additional storage demands in virtualized environments, driven by latent demand and ease of provisioning."

The survey respondents come from a variety of industries, and all of them are users of VMware virtualization software. That isn't surprising, since they all attended VMworld 2007, which is where Xiotech got their names. Some 69 percent said they had more than 100 servers in their data centers.

As might be expected, these IT managers are among the leaders in adopting virtualization. Some 32 percent said up to 25 percent of their production environment is virtualized; 24 percent said they had virtualized between 26 percent and 50 percent; 22 percent said they had virtualized between 51 percent and 75 percent; 12 percent said they had virtualized up to 90 percent of their production environment; and 9 percent claimed to have virtualized between 90 percent and 100 percent.The top applications run on virtual machines were Web servers (cited by 93 percent), file servers (76 percent), databases (71 percent), print servers (63 percent), accounting and financial applications (58 percent), and virtual desktops (41 percent). Other apps run on virtual machines included CRM, ERP, and MRP.

Some 80 percent of survey respondents use a Fibre Channel SAN while 13 percent use an iSCSI SAN.

Asked why they moved to a virtual server environment, 95 percent said to consolidate servers and reduce their server footprint, 83 percent said it was to increase server utilization, 63 percent said it was to reduce power consumption, and 62 percent said they did it for disaster recovery.

As for backing up data, 43 percent said they used tape backup of individual virtual machines while 24 percent said they used disk-to-disk-to-tape backup of individual VMs. Some 11 percent did storage system snapshots of VMware Server Volumes while 10 percent did disk-to-disk-to-tape backup of VMware Server Volumes.

An interesting split in job duties showed up when the survey asked if the same person managed the virtual servers and the storage -- 49 percent said yes and 49 percent said no; 2 percent didn't know.Diving deeper into that last stat, the survey results showed that 70 percent of companies with fewer than 1,000 employees had a single person managing the virtual server environment and the storage environment. In larger companies, 70 percent had different people managing the two technologies. That can pose a challenge in terms of communications and utilization of overall storage, Eric Lomascolo, director of product management at Xiotech, told <="" i="">."In a VMware environment, the three layers of management -- storage, ESX, and virtual machines -- can cut down on visibility and make it difficult to track and provision storage consistently," he said. "That can result in increased labor costs if you have to go back and review all of the layers and the utilization. It is easy to lose sight of what has been provisioned and is being utilized. "

Xiotech, of course, offers a product to help deal with such issues. The company's Virtual View plug-in for its ICON Manager, both available at no cost to customers, is designed to help with storage provisioning and reporting in virtual server environments. When used with the company's Emprise and Magnitude 3D storage systems, Virtual View provides insight into the storage array, the physical server, and virtual machines from a single console and can automate configuration and provisioning across all three layers, the company said.

"The idea is to pull the three layers of the ecosystem together and manage them as a single pane of glass," Lomascolo said. "We were able to do this through Web services, so customers can develop their own automation techniques as well and operate as a single system."

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