Storage area networks (SAN) are being installed and deployed more frequently today, but uncertainty still exists among users about why to install them and the applications that can make the best use of them. SANs are high-speed networks, similar to LANs, that connect disk subsystems directly to servers or clients. The idea is to relieve network congestion or bypass distance limitations imposed by traditional SCSI storage connections.
Fibre Channelbased SANs can be configured in several ways and for any number of reasons. They can be installed and deployed as Fibre Channel Arbitrated Loops (FCAL) or switched fabric networks. They can be local or remote, spanning campuses and using wide-area connections.
Methods for implementing SANs may differ, but most network professionals offer the same recipe from one installation and deployment to another: Start small and think globally. They recommend implementing small, simple FCAL or switched fabric networks to share data among servers.
You need to approach SANs with a broader plan than simply to drop in more storage and see if it is going to be successful. You also need to plan not only where you are today, but where you want to be tomorrow, and then consciously choose the applications that work in the context of a bigger picture.
So, at this point, if you are still wondering what is a SAN, why deploy a SAN, what applications are driving SANs, whether you need to implement a SAN, or how best to minimize the impact of a SAN implementation on the enterprise, this article has the answers for you. The article discusses with you how the benefits of a storage area network have solved numerous problems for users. Nevertheless, many users remain cautious. One of the main reasons for this is the suspected of lack of interoperability among servers and storage devices.
Interoperability issues have stabilized significantly since 2000. Both products and users have matured. This article addresses those issues for you. It explains to you how to leverage existing technology when installing and deploying a storage area network. Your comfort level is very important here.
Look to Your Applications
You also look at your applications to determine which applications warrant adding a SAN and which will do just as well on server-attached RAID. It is recommended that you begin with a small, low-impact or low-budget application, such as consolidating several servers to the same storage device, before moving to full-blown implementation. From this application, users can test the proof of concept and then grow the SAN to involve more of the routine tasks of the data infrastructurefor example, replicating data and creating multiple active copies of data that would increase utilization or ease maintenance and testing operations.
It is also recommended that users divide applications into categories based on importance. For mission-critical application data, users need to design in redundancy and fault tolerance with duplicated storage, switches, and host bus adapters so that there is no single point of failure.