This article can also be found in the Premium Editorial Download "Storage magazine: Using two midrange backup apps at once."
Download it now to read this article plus other related content.
There are three main ways to back up virtual servers. Here's how to determine which method is best for your storage requirement.|
SERVER VIRTUALIZATION IS supposed to simplify IT, and it does, except for one little caveat: It currently complicates backup and recovery. Companies quickly discover they can back up their virtual servers the same way they do their physical servers, but they may not get the same results.
"It's simple to back up virtual servers if you treat them like physical servers," says Scott Polly, director of technical publications at Vizioncore Inc., Buffalo Grove, IL. The firm provides vRanger Pro, a GUI-based application that automates much of the command line scripting typically involved in VMware backup. Simple, but "you don't get the benefits of server virtualization," adds Polly.
The benefits Vizioncore's Polly refers to revolve around efficient management. If you treat virtualized servers like physical servers, you have to manage each individually, which undercuts any improvements in management efficiency. You also have to buy and install a backup agent on each virtual server as if it were a physical server, which will certainly require more work and may entail additional license fees depending on your backup product. In short, storage admins face more than the usual backup complications because there are
| more virtual servers and they have to run multiple concurrent backups.
In addition, the immaturity of server virtualization makes the backup challenge more difficult. VMware is still feeling its way when it comes to backup and recovery. "It's hard to get clear documentation," reports John Dolan, principal consultant at Viant Solutions in Suwanee, GA. Dolan had been trying to pin down the backup of 24 virtualized servers spread across three hosts at Perimeter Church, a mega-church based in Duluth, GA, but getting accurate information was frustrating. Early on, he feared he might need to write some software to make the church's version of Symantec Corp.'s Backup Exec (Version 10d) work with VMware ESX 3.0.2.
The solution turned out to be simple once he had the correct information. "Backup Exec [Version 10d] simply isn't supported by ESX 3.0.2," says Dolan. He finally discovered that after digging through VMware's latest compatibility guide. "We needed to be running Backup Exec 11d or later," he says. That meant Perimeter Church had to upgrade to the next release, which entailed an added cost. "But we'll only need one server license plus the Exchange and SQL license for our virtual servers," he adds.
The VMware backup picture is changing almost weekly as VMware pushes out new documentation and products, as more vendors scramble to certify their backup tools with VMware and as consultants begin to identify some best practices (see "Virtual backup best practices," below). VMware insists that backup isn't difficult: "It's not hard, but different," says Jon Bock, VMware's senior product marketing manager, adding that "it will change what you're probably doing now."
This was first published in September 2008