* NAS Gateway
This is the second in a three-part series talking about the latest trends in network-attached storage. Over the past year, there has been a lot of attention paid to making NAS appliances more flexible, scalable and improve performance. Last week, I discussed the performance enhancements provided by the introduction of TCP/IP offload engines into the NAS appliance. This week, I will discuss how vendors are addressing the flexibility and scalability issues sometimes encountered in environments with very large NAS deployments.
In traditional NAS environments, the NAS appliance comes with storage already attached, similar to other application servers that have storage directly attached to the system. The smaller appliances only support the storage that arrives with them, forcing customers to purchase another appliance when their capacity requirements exceed the boundaries of the small appliance. In the larger NAS appliances, the storage is placed in racks and can be added as the need for storage increases. However, what happens when the applications’ storage requirements exceed beyond the bounds of what can be attached directly to the appliance?
A good number of these larger appliances are found in corporate data centers, most of which have also implemented storage-area networks (SAN). One of the greatest benefits of a SAN is its ability to scale indefinitely. That, combined with the ability to share storage capacity across multiple applications, made combining NAS and SAN technologies inevitable. Companies such as IBM, HP, EMC and Network Appliance in partnership with Hitachi Data Systems are a few of the larger companies that have products that meld SAN and NAS in the form of a NAS Gateway.
The idea of a NAS Gateway is really quite simple. The Gateway consists of the system component that has been optimized to server files, also known as a filer. These Gateways then connect to the SAN storage on the back end, allowing IT to provision the storage to the NAS Gateway in a fashion similar to how they provision storage to other applications using the SAN storage. This allows the storage behind the NAS Gateway to scale to very large capacities, as the environment requires. The combination of NAS appliance technology and SAN technology can provide customers with an excellent solution to the inherent scalability issues in NAS environments.
Next week, we will take a look at bringing to bear another technology in NAS environments that combine scalability and performance advantages.
