Recently, I had the opportunity to sit down with Compellent and spend some time talking with them on a few hot topics. High on my list to talk about was getting their impression of the bidding war for 3Par. We discussed that subject and much more. I have been meaning to blog about Compellent for some time, taking a deeper look at their Auto Tiering capability, which is leading Compellent into enterprise opportunities. It appears the time is right to provide a glimpse into a storage company that has started to take on the enterprise challenge.
One topic we discussed was Live Volume. Live Volume has been talked about by Compellent for a couple of years. First there were some teaser blogs on the company's website describing what was to come and how it would help in an IT environment that required duplicate copies of data to be located in disparate locations. Based upon Compellent's description of Live Volume, one could easily envision two live asynchronous, and perhaps bi-directional replication operations between two storage controllers, or storage clusters, and how that would be valuable in some site failure scenarios. It seemed like a business continuity and disaster recovery solution was in the works. As it turns out, time and testing has proven Live Volume across multiple connectivity protocols and within a VMware Vmotion environment.
Today, based on an evolved Live Volume architecture, Compellent supports the offering within an active Vmotion environment. In fact, Live Volume can detect when VMware Vmotion moves a virtual machine from one server to another. Immediately after the detection of the virtual machine move, Live Volume will flag the replicated secondary volume as the new primary and will automatically reverse replication direction.
Should the virtual machine move back to its original server, Live Volume will automatically reverse the direction of replication again and flag the original primary volume as back to primary again. Compellent supports this functionality across Fibre Channel, or iSCSI - naturally users of an iSCSI solution are encouraged by the company to utilize 10GbE for better replication performance.
From an architectural perspective, the number of Live Volume pairings is limited only to the available bandwidth, although I anticipate the company will release best practices guides and reference architectures to assist its partners and customers with practical implementation. Live Volume has been in General Availability (GA) for some time now, and Compellent considers Live Volume to be a family of products. I am sure we will see some number of Live Volume family members announced and in GA in the near term.