Consolidating servers and data centers is a great way to cut support and infrastructure costs. IBM estimates its own project of migrating from 3900 servers to 30 System z mainframes will save the company $250 million in energy, software and support over the next five years.
But migrating the data and applications takes careful planning to ensure the move goes off without a hitch. When the Defense Contract Management Agency (DCMA) went from 18 data centers to two, it used VMware’s virtualization middleware and Network Appliance, Inc.'s Virtual File Manager (VFM) to consolidate the data prior to migration.
“We used to do file migrations manually using a lot of DOS scripts,” says Peter Amstutz, chief of network design at DCMA’s Carson, CA data center. “VFM saved us 500 to 1,000 hours of work in moving data.”
Slashing Server Support
The project involved several actions. One was to reduce the number of servers by using VMware's Infrastructure. The DCMA began looking at virtualization in mid-2005. At that point, the agency had about 625 servers, and was replacing 200 of them annually. In November of that year, it started using VMware virtualization technology, buying 60 new servers instead of the usual 200. In subsequent years, it only needs to buy 20, saving the agency nearly half a million dollars annually, not counting power, cooling and labor costs. Earlier this year, the DCMA upgraded to the latest version – VMware Infrastructure 3 – which virtualizes servers, storage and networking.
In addition to consolidating the servers, the DCMA also needed to set up a common file system that would work across the enterprise. For this it created a File Area Network (FAN) using software and storage appliances from Network Appliance. The DCMA has over 300TB of storage.
When it consolidated its data centers, the agency went from 56 file and print servers down to two clustered NetApp Filers – the FAS3020C and FAS6070C – at each site: the DCMA's primary data center in Carson and another in Boston. The 3020Cs are used for file sharing and the 6070Cs are in a SAN. NetApp’s VFM was used to migrate the files from the file servers to the NetApp appliances.
Amstutz says it is much simpler backing up from two locations rather than 18. The agency uses backup software from CommVault of Oceanport, N.J. and NetApp VFM to snap mirror the data to NetApp R270C boxes using SAS and SATA drives. Future plans are to use VFM to replicate the data between the Carson and Boston for failover.
While the consolidating the storage did make it easier to administer, it did introduce a latency problem. When there were 18 data centers, there was always one close enough to the end users to avoid any issues. But when users are more than 1200 miles apart, latency starts affecting replication and file sharing, delaying traffic and causing resends. With only two data centers positioned at opposite ends of the country, the DMCA installed WAN optimization appliances from Riverbed Technology, Inc. of San Francisco to reduce the latency.
Virtualize Files First
The consolidation did come off as planned, but Amstutz says he would do things differently if he had the opportunity to do it over again. To begin with, he says that it would have been better to use the VFM to create a global namespace for all the files before the migration.
“Today each organization has a drive mapping that takes you to a certain file share,” he says. “This makes it harder to collaborate because, if you are trying to share files with an organization at a higher level than you, you can't see what each other sees.”
Even if the DCMA hadn't consolidated the data centers, he still would have used VFM to create a single virtual file structure so all locations. Nevertheless, even without the file virtualization, installing VFM was still well worthwhile.
“NetApp VFM has paid for itself just from the file migration alone,” says Amstutz. “But if I had it to do all over again, it would have been much simpler to virtualize our file systems first and then migrate.”
This article was first published on EnterpriseITPlanet.com.