Data protection in a virtual world

Server virtualization has become the number one project in most IT organizations around the world. CIO's around the planet are looking to improve their IT cost structures, and it just makes sense to consolidate existing server footprints onto more powerful platforms that are much easier to manage and protect, while enabling organizations to reduce server footprints tenfold or more. The savings in floor space, power and cooling alone can sometimes pay for the migration to the new infrastructure. Abstracting application servers from the physical vendor hardware has the added benefit of commoditizing servers, which also lowers capital expense.

A few of the benefits of server virtualization are:

• Application mobility
• Increased efficiency in hardware utilization
• Power savings
• Smaller datacenter footprint
• Commoditization of server hardware
• Simplification of server management
• Standardization
• Simplified disaster recovery

There is no such thing as a free lunch, though. There is always a tradeoff when doing things differently. Where standalone physical servers can use 100 percent of all the resources provided, server virtualization forces the applications being hosted on the virtual server to share physical resources among many hosted instances. They need to share memory, I/O adapters and CPU time, and backup can be a problem if all the servers do it at the same time. Therefore, the physical resources and data protection methodology of a virtual data center need to be managed more closely than with a pure physical server plant. 

Some of the downsides of server virtualization are: 

• Application performance
• I/O performance
• Backup impact
• More complex resource management

Even though the benefits of server virtualization far outweigh the drawbacks, it's always a good idea to know the facts and be prepared. Our friends over at the ESG group put out a report on the impact of server virtualization on data protection that may be of value. If you have a Gartner account, check out its report called, "Best Practices for Addressing the Broken State of Backup," which may also be of use.

My own CEO, Jim McNiel, summarizes the impact of server virtualization on data protection as follows:

"Virtualization breaks backup for two main reasons. First, we are consolidating a lot of compute and storage power into a smaller number of servers, which stresses the available I/O. Second, virtualization introduces a new data format that challenges legacy backup solutions and at the same time presents a whole new world of data recovery opportunities."

The good news is that as the virtualization paradigm matures, new offerings are becoming available that  alleviate some of the drawbacks of virtualization and the impact of data protection on virtual server plants.

For example, VMware's own site recovery manager (SRM) improves the ability to protect and recover virtual servers during an outage that effects the entire data center. Continuous data protection solutions and snapshot technologies are now adding intelligence to integrate with virtual environments in order to take the bulk copy process out of backup and recovery for virtual servers.  Additionally, a new and exciting area of development called services-oriented data protection (SODP) together with virtualized storage is enabling organizations to tie together the benefits of virtualization on both server and storage environments to reap real cost benefits. Our buddies at Wikibon have an article by Dave Vellante on the subject called, "Service-oriented storage: An idea whose time has come," which is similar in concept to the data services engine blogs I have been writing.

In the end, the power of virtualization is making a huge impact on IT. Server and storage virtualization together enable the IT organization to spin up services as needed, failover seamlessly to fully functional replica servers or sites (running a complete, fully functional service) in the event of a fault, and even replicate the entire data center to a completely virtualized DR site in the cloud. When data protection just becomes an automatic service built into the solution, the story gets even better.

Christopher Poelker is the author of Storage Area Networks for Dummies, and he is currently the vice president of enterprise solutions at FalconStor Software.