One of the big advantages of performing snapshots is that they reduce the recovery point objective and recovery time objective for a virtual server backup. They also help optimize server performance.
Consider a popular virtualization backup technology like VMware Consolidated Backup (VCB). In this case, a virtual machine (VM) is duplicated to a separate server that executes a backup process to disk or even tape -- any I/O load on the backup server does not affect the production server at all. Similarly, VM snapshot backups performed through storage subsystem utilities have little effect on the server hosting that VM.
Optimize server performance during backups
A more significant concern for virtualization backup planners is the need to pause applications running in VMs during the process. This is typical when the backup tool is not virtualization-aware.
When the application is paused, it is unavailable to users and can reduce productivity, even for a few minutes at a time. Although many backup tools will protect VMs, organizations should opt for virtualization-aware tools that need not pause each application, which helps optimize server performance.
Software changes are another tricky area. In a traditional virtualization backup, patching or updating the backup tool to another version can cause unexpected changes to the backup workflow or leave existing backups inaccessible. Backup software updates should also be a critical area in a virtualized environment -- an even greater concern now that so many VMs are involved. Testing is also essential before rolling out a new virtual backup tool.
Ultimately, experts advise careful planning when you optimize server virtualization backup. Consider the interdependencies of servers computing resources, VM distribution, software tools and storage requirements. The backup scheme must be appropriate for your business needs and goals.
Trends in virtualization backup
The next 12 months for virtualization backup promise an evolution rather than a revolution. Virtualization technology is quickly moving into the mainstream, and vendors of all sizes are taking steps to provide virtual support for all types of products.
"We're seeing third-party support vendors and all the pieces around network infrastructure start to create virtualization-aware products," said Dave Sobel, CEO of Evolve Technologies, a solutions provider in Fairfax, Va.
He added that even disk defragmentation tools like Diskeeper are now virtualization-aware.
As tools like VCB continue to evolve, other virtualization backup tools should become more extensible, more interoperable and more transparent. Backup agents should also become more efficient, reducing their footprint when installed onto individual VMs.
Improvements in virtual backups should also be driven by fierce competition between manufacturers -- starting with leaders such as VMware, Citrix Systems Inc., and Microsoft. End users can only benefit from competition, which should also trickle down to the ranks of third-party backup product vendors.
About the author
Stephen J. Bigelow, a senior technology writer in the Data Center and Virtualization Group at TechTarget Inc., has more than 15 years of technical writing experience in the PC/ technology industry. He holds a bachelor of science in electrical engineering, along with CompTIA A+ and Network+ certifications, and has written hundreds of articles and more than 15 feature books on computer troubleshooting, including Bigelow's PC Hardware Desk Reference and Bigelow's PC Hardware Annoyances. Contact him at firstname.lastname@example.org.
This was first published in May 2010