Storage 102: Managing Multi-Vendor Storage Networks

Not too long ago, storage and networking decisions were simple. There were fewer options, fewer vendors, and fewer technologies to choose from. These days there are more vendors, more networked storage methodologies, and new technology is introduced daily. Today, there are as many ways to network storage, as there are operating systems. Currently, the most popular storage networking methodologies are direct attached storage (DAS), storage area networks (SAN), and network attached storage (NAS). Historically, direct attached storage--or DAS--has been the most popular networked storage decision. This option, while being a solid platform, presents issues with regards to reliability and scalability. Newer storage technology has recently been introduced, addressing the shortcomings of DAS--the most resilient of these systems being SANs along with a growing market for NAS. As opposed to DAS, SAN and NAS offer higher performance and greater levels of scalability enabling IT organizations to offer and meet service levels.

Regardless of company size, a well-built and well-managed storage network can increase efficiency for not only the company, but also for IT organizations. The concept of a storage network is simple; connect enterprise servers to a centralized pool of disk, easing administration, increasing performance and making data backup more reliable. A typical SAN consists of high performance but complex devices making up the data path. A group of highly intelligent devices including host bus adapters (HBA's), switches and storage arrays make up today's SANs. As intelligent as these devices are, they still need a good deal of managing. There are many vendors providing both NAS and SAN solutions for storage networks, but no single vendor provides a complete data path solution, making interoperability and effective management of storage networks a challenge.

Basic Management
Many administrators track and provision their storage resources by using spreadsheets and inventory reports that are immediately outdated. A storage network management framework eliminates this manual task by automatically discovering the physical and logical connections of the storage network, displaying the information in a graphical topology map, and logging the data in a variety of reports. Storage networks are complex environments comprised of many components including clients, application servers, switches, hubs and storage devices. As a storage network evolves and grows, it becomes more and more difficult to accurately identify all of the components and their physical relationships to each other. In addition, mapping of the logical view (virtualized storage) adds to the complexity because there may not be an obvious direct physical relationship. It is critical for administrators to have both the physical and logical views made available in a topology that easily identifies all of the components as well as the physical relationships.

An important feature of any storage management framework is the ability to track both real-time and historical performance data for critical service-level parameters such as connectivity, available space, and throughput. Intelligently using all available storage resources, IT administrators are able to make highly educated decisions by using integrated reporting, tracking and management features in conjunction with pro-active response and notification facilities. By doing so, IT organizations are able to monitor their environment and be ready for change at a moment's notice, putting IT managers in control of service levels.

Advanced Management
Once administrators have realized the power of automatic discovery, visualization and reporting features in a management framework, they can begin to use more advanced features like security, storage provisioning, and proactive management of their resources.

Ensuring that applications have the storage resources they require means providing secure storage from arrays and backup devices to the hosts within the storage network. An advanced storage management framework provides integrated storage masking and zoning from storage arrays to hosts through easy-to-use wizards. Wizards mask the complexity and ease the management of advanced storage management tasks like LUN binding, LUN Masking and zoning. Advanced features should also offer services that ensure critical applications get the quality of storage service they require. Tools allowing administrators to accurately search and allocate storage by attribute, providing intelligent provisioning should also be utilized. By enabling administrators to search for storage with attributes that match the requirements of the application, they can more effectively match applications to storage.

Tying it all Together
Storage network management frameworks have been developed to empower IT organizations with the flexibility to respond to changing business priorities. Using all the features of a powerful storage network management framework enables IT organizations to respond quickly and change resource allocation while minimizing the impact on the business. A basic management framework should provide IT administrators the ability to perform discovery, visualization and monitoring of their storage network. Advanced storage management solutions should provide the ability for active management. Active management enables IT organizations to proactively establish policies and monitor performance, rather than reacting to problems as they occur. Proactive management leads to greater consistency and efficiency of service. IT admins do things in a reactive mode when outages or crashes occur that might not follow the established policies. Their goal is to get systems back in operation quickly so it becomes acceptable and understandable for them to do what needs to be done. Reactive environments, by definition, are interrupt-driven which negatively impacts productivity. It is not very efficient to grow the business if IT administrators are pulled off a planning project to cope with application performance or storage capacity issues.

A powerful storage management framework should do all of the above as well as allow IT organizations to adapt to an ever-changing technology environment, providing the flexibility to adopt new technologies as they are introduced. IT managers need to be able to explore and take advantage of new technologies and architectures without putting service levels at risk. The cost of those technologies is not just the hardware cost--it's not just the cost of a server or storage array from a different vendor or even a different topology. The more significant component of cost and risk is the cost of re-training people and retooling all the established processes. It is critically important that managers optimize the use of their biggest costs--people. Highly trained administrators need to work strategically--to design best practices that can be deployed consistently across the organization by less-skilled personnel. The only way to effectively and efficiently accomplish this, is by empowering applications designed to offload the burden and introduce simplicity to complex environments.