Navigating Virtualization Storage Waters With EMC's Navisphere Manager

Server virtualization continues to be near the top of the IT top priorities hit list. A recent Goldman Sachs survey of IT spending priorities showed server virtualization in third place followed by closely-related server consolidation in fourth place. And both are closely correlated with the #1 (and not at all surprising) IT spending priority of cost reduction.

But new technologies can also introduce new challenges and complexities, and so it is with server virtualization's relationship to storage. With direct attached storage (DAS) the horse and carriage relationship between servers (CPU horsepower) and storage (data carriage) was clear. Both the physical server and its storage were tightly coupled in a one-to-one relationship (each server and the storage that it "owned"). Even though the introduction of storage area networks (SANs) physically decoupled servers from storage, still each server was physically assigned an allocated piece of the SAN storage infrastructure. So, the relationship between a server and storage was clear even if the assignment of storage could be changed from time to time (which was not possible with DAS). Thus, the distinction between a server as a physical device and a server as an operating system and the software environment that it controlled was irrelevant.

That situation has changed fundamentally with server virtualization with the result that storage has relationships with virtual machines (VMs) instead of physical servers. And VMs themselves are not tied to a particular physical server, but can move around as needed, such as for load balancing and performance reasons. That capability is very powerful and very useful for the management of workloads and application performance. However, at the same time, storage administrators now face challenges in gaining visibility into which VMs are consuming which storage resources. This is necessary to ensure that VMs have the storage that they need to run effectively, to ensure that the overall performance of the server-storage environment meets service level agreements, and to be able to resolve any problems that may arise.

Quite clearly, without the proper software management tools achieving those goals can be very challenging. The problem up until now has been that performing virtual infrastructure discovery and reporting necessary for management of the virtual environment, including storage, was very difficult. And that meant that managing the virtual environment of VMs working with storage was difficult, at best. 

EMC's introduction of new automated virtualization-aware Navisphere Manager capabilities for CLARiiON CX4 has changed all that. The company cited an example of a medium-sized VMware environment of 100 VMs spread across 10 ESX servers in which the storage administrator had to view 200 screens for the 10 ESX servers and then record the information on each screen manually to a spreadsheet! Naturally that required hours to complete, but to further compound the problem, the process needed to be repeated to reflect any change to the environment. Obviously, this was a task that overburdened administrators did not look forward to and one that cried out for automation not only to free up time, but also to reduce the possibility for error. But a proper solution should also not inhibit VMware administrators from moving VMs as needed without having to worry about recording and management issues.EMC's new Navisphere Manager solution supports automated changes to the discovery and reporting processes, requiring only two screens to report the latest virtual to physical mapping and to export automatically to an Excel or CSV. EMC says that the process takes only seconds to complete in contrast what used to take hours. Frankly, that takes an unmanageable manual process and turns it into an eminently simple automated feature.

But Navisphere Manager also addresses issues well-beyond infrastructure and process management. Previously, VMware administrators were not storage-aware and storage administrators were not virtualization-aware. Enabling the storage administrator to become virtualization-aware occurs through an enhancement to Navisphere Manager. On the server virtualization side, the VMware administrator can use the EMC Storage Viewer for CLARiiON, a free downloadable VMware vCenter plug-in, to become storage aware. 

For the VMware user, EMC's Storage Viewer provides integrated views of the relationship between VMware virtual machines, disk files, datastores, and underlying CLARiiON storage systems, information that can be used to check for best practice settings.  For the storage administrator, the enhancements to EMC Navisphere Manager for CLARiiON CX4 enable automatic discovery of virtual machines and ESX servers, with end-to-end virtual to physical mapping, and new advanced search for instant VM discovery capabilities. 

Mesabi Musings

The introduction of a new technology, such as server virtualization, may spawn new challenges and complexities. Addressing these issues can only occur as a new technology becomes widely adopted and mature. Before that the challenges were either not recognized (as no one had enough experience previously) or not relevant (as the potential challenges were at too small a scale to matter).VMware continues to maintain a strong leadership position in server virtualization through the introduction of more powerful and useful capabilities that extend the breadth and depth of doing server virtualization implementations. But, in the process of doing so, the challenges and complexities of dealing with storage in conjunction with these capabilities, such as the ability to move VMs fluidly for better load balancing and performance, has become apparent. 

With its new Navisphere Manager and Storage Viewer capabilities, EMC has virtually eliminated storage management challenges and complexities arising from the broader deployment of server virtualization. Not only will this improve the productivity of both VMware and storage administrators, but may very well help remove a potential inhibitor to the fuller deployment of server virtualization. Virtualization may cause the server "horse" to be connected to the storage "carriage" in a different way but the connection still exists. Overall, IT organizations should look favorably on EMC's new software capabilities.