California State University, East Bay (CSUEB) had planned a new data center, but it would not be available for two years. The data center was using 67kVA and the maximum power available from the utility plant was 75kVA. In late 2007, CSUEB averted a crisis by implementing virtualization for both their server and storage environment. By the end of 2008, 25 servers had been shut down, 17 NAS devices had been migrated and turned off and 21 new applications that would have required additional servers have been installed. Power consumption had been reduced by 26% and tens of thousands of dollars in electricity costs had been saved resulting in a much more efficient data center.
CSUEB teaches us a powerful lesson of data center optimization through virtualization with quantifiable results. As power consumption continues to push more data centers towards the limit, virtualization offers a potentially effective solution to
- Reduce power
- Remove aging technologies that have become costly to operate
- Get rid of unnecessary things in the data center, and attack underutilized devices
- Shrink footprint (physical and carbon)
The CSUEB study identifies tangible benefits of synchronizing server virtualization with storage virtualization. Storage virtualization is the pooling of physical storage from multiple network storage devices into what appears to be fewer storage devices which are managed from a central console. Storage virtualization is commonly used in a storage area network (SAN). The management of storage devices can be tedious and time-consuming. Storage virtualization helps the storage administrator perform the tasks of backup, archiving, and recovery more easily, and in less time, by disguising the actual complexity of the SAN. However businesses are increasingly aware that embarking on a virtualization project without a legitimate plan, consider the following issues:
- Before server virtualization occurs, a few people depend on each physical resource and hardware changes are much more confined to a small group of users
- After workloads are concentrated, there is an increased dependency on storage subsystems to perform at higher levels
- Virtual servers allocate disk capacity per virtual machine and create “templates” that reserve disk capacity that may or may not ever be consumed. The case for thin provisioned storage makes it efficient and easy to create volumes for any number of virtual servers without wasting storage capacity
- It ensures that any unused storage resources are available to basically any application or operating system
- Thin provisioning and thin replication technologies can significantly improve underutilized disk storage on non-mainframe systems which averages about 40% at best.
- The advent of the new thin technologies can reduce necessary disk capacity and the associated carbon footprint by as much as 60% as compared with traditional fat storage
- Be aware that increased levels of virtualization can make performance tuning and capacity planning more difficult as it becomes more complicated to attribute the actual measurements to physical hardware
Action Item: It’s common to go after servers but ignore storage virtualization. Synchronizing both storage and server virtualization can result in improved storage utilization on both the server and SAN side. Having both server and storage virtualization synchronized so you can balance the two together presents the data center with an excellent opportunity to re-architect IT.
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