Disk-Based Backup Does Not Magically Break The Corporate LAN Bottleneck

By Jerome M Wendt, DCIG LLC

It's easy for organizations to believe that disk will solve their backup problems. But some organizations are starting to discover that while disk solved some of their backup problems, they are still not realizing the full reductions in backup times and improved performance rates on their application servers that they may have initially expected. If an organization finds itself in this predicament, then it probably behooves them to take a closer look at their backup architecture and determine exactly how much backup traffic is going across their corporate LAN. The problem that can potentially emerge in a disk-based backup architecture is the corporate LAN can become a bottleneck when a backup server is directly attached to a virtual tape library (VTL). As backup data is sent by the backup agent on the application server to the VTL attached to the backup server, the data is piped through the application server, sent over a 1 Gb LAN connection and then funneled through the backup server to which the VTL is attached. So while the backup to the VTL attached to the backup server may complete successfully, going through all of these touch points can slow down the backup and introduce overhead on both the application and backup servers.