Virtualization Makes Disaster Recovery Cheaper Page 2
More Options for Disaster Recovery Sites
Not only does virtualization save on hardware outlays, it can reduce real estate expenses too, especially for companies already doing business at multiple locations.
Traditional disaster recovery schemes often call for redundant hardware to be located offsite at dedicated data recovery centers, ORourke said. "Now companies can make it part of their general IT operations," he said. "A business with locations in multiple cities around the country or the world can use those other sites as backup sites."
What's more, he added, their DR system can be created with standard off-the-shelf hardware and storage. "It makes it much more affordable," he said.
IBM's Robinson said virtualization can improve recovery times. "Activating a canned virtual image is much quicker and easier than bringing up a new physical machine," he noted.
Robinson estimated that firing up a new server can take from 20 minutes to several hours, depending on complexity. "Whereas bringing online a virtual image is pretty much instantaneous," he said. "It's like a virtual on-off switch."
Backing Up Virtual Machines
Virtualization has removed much of the toil involved with restoring operations from a disaster recovery system, according to Eric Schou, a senior product marketing manager at Symantec (NASDAQ: SYMC. "DR has been made pretty easy and very straightforward in the virtual world," he declared.
By creating backup files that contain both the operating system and data files for applications, virtualization removes much of the fuss associated with restoring backups, Schou said.
However, there have been some snags associated with backing up virtual machines, he noted. For example, there are two ways to backup a virtual machine. One backs up an entire image of the machine; the other, individual files. To take advantage of the benefits of each method, separate backups using each methodology must be done. That doubles the storage requirement for the backup.
Another complication is the inability to make incremental backups of virtual machines. That, too, boosts storage requirements.
Schou claims Symantec is the only vendor that addresses those problems. Its software can perform incremental backups, so only changes to the image of a virtual machine are stored when a backup is made. It will also perform a single backup that can be used to restore an entire virtual machine or individual files from it.
As beneficial as virtualization has been in improving server efficiency, that benefit has been a double-edged sword, said Schou. That's because before virtualization, only eight to 12 percent of a server's processing power was being used. "What's happened with virtualization is we've seen companies take that same server that was running eight to 12 percent and now run it at 80 percent or more," he said.
"From a backup perspective, that makes things very challenging," he continued. "You've got to ask yourself, where's my backup window? It doesn't exist any more."
To solve that problem, Saul said, companies can perform backups "off-host." That entails adding a media server to the mix. "The media server doesn't have to be dedicated to the virtual infrastructure," he said. "Many folks have this box already. Depending on how large or small your virtual environment is, you can share that box."
"This idea of doing the backup off-host is really where customers see the future of having successful overall protection of their environment," he added.
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