Friday, December 22, 2006

Global namespace: The Future of File System Management, Part 2 - Storage Networking

IT administrators spend a great deal of time on file management tasks (adding users, adding file servers, rebalancing storage, setting up failover, etc.) and data movement tasks (replication, migration, consolidation, data distribution). These are tedious and time-consuming for administrators, disruptive to users, and expensive for companies.

Companies are looking for better ways to scale and manage their file systems. Global namespace provides the answer.

In "Global Namespace--The Future of File System Management, Part 1," we defined global namespace as a logical layer that sits between clients and file systems for purposes of aggregating multiple, heterogeneous file systems, and presenting file information to users and applications in a single, logical view. The benefits of a global namespace are clear and compelling:

* Users (and applications) are shielded from physical storage complexities. Administrators can add, move, rebalance, and reconfigure physical storage without affecting how users view and access it.

* Global namespace provides a platform for developing value-added functions such as data migration, server consolidation, and disaster recovery.

With a global namespace in place, the administrator can perform data management and data movement tasks in less time, without disrupting user access to files. When files are moved, links in the namespace are automatically updated, which reduces manual administration and ensures continuous client access to data.

In this article, we will discuss how a global namespace simplifies file management, how to create and deploy a namespace, and the solutions it enables in an enterprise environment.

The Problem: File (Data)

Management and File (Data)

Movement

Stephens Company has 600 marketing and engineering users who are accessing files across five file servers that are shared by the two departments located in Houston and New York City. Marketing users are accessing files via multiple drive letters that are mapped to two NetApp filers and a Windows server, and engineering users are accessing files on three servers and one filer.

There are several issues with Stephens Company's current file system environment:

* Users find it difficult to locate and access files via multiple drive letters (which are increasing).

* File server Houl_W2K_Server12 is at 90 percent capacity, while NY_NAS_Server2 is at 20 percent, which means that users are beginning to get errors as they try to save large graphic files to Server12.

* To migrate files and rebalance storage between Houl_W2K_Serverl2 tY_NAS_Server2, the administrator must disable user access to the files that are to be moved, move the files to the NY filer, reboot and bring both devices back online, revise all marketing and engineering user login scripts, and inform users that the files have a new location so that their PCs can be reconfigured to access them. This will require at least 12 hours of downtime and the manual reconfiguration of every desktop and application that accesses the files.

The Solution: Global Namespace

There is a simple, long-term solution to Stephens Company's data management and data movement issues. Deploying a global namespace will simplify data management and enable transparent data movement.

Figure 2 shows the new configuration, in which a global namespace has been inserted between users and physical storage. Users now access their files through shares called \\namespace\users\marketing and \\namespace\users\engineering. This was a non-disruptive installation, as the namespace was installed on top of the existing infrastructure. Users continue to access files in the same manner as before, with no retraining needed.

Note how the file system environment is changed by the introduction of a global namespace:

* All users see a single, logical view of files through the namespace.

* Users access all their files through a single drive letter--which will not grow, and allows them to continue accessing files in a familiar way.

* Data can be organized and presented to users in a way that makes sense to them, irrespective of how or where the data is stored.

* Data management and data movement are performed "behind the veil" of the namespace.

* Data changes are automatically updated in the namespace, and require no client reconfiguration.

* Administrators can expand, move, rebalance, and reconfigure storage without affecting how users view and access it.

* Data management and data movement require far less physical administration and are performed in less time than before.

Having a global namespace in place makes it easy for IT managers to accommodate the changing needs of an organization while also reducing storage costs.