Page 9 of 12 July 2001 Why Choose Native Fibre Channel Backup? Library capacity and performance can be expanded by simply adding new drives, without the configuration hassles of a router.  Drives can be hot-plugged into the library without interrupting library or SAN operations. Note that while some tape libraries claim to be native Fibre Channel, they really just contain an integrated router.  If the internal router fails, the entire library and its drives are out of commission.  The router cannot simply be swapped out, so repair is expensive and time-consuming. True native Fibre Channel libraries from Exabyte eliminate the router failure point and provide enhanced reliability, throughput, and cost-effectiveness for the SAN. Serverless backup removes the server bottleneck Without question, sending backups through a SAN relieves networks of the problems associated with massive data transfers.  However, even on a SAN, most backup systems require servers to process the data transfers.  The server itself becomes a bottleneck as data moves from disks on the SAN to server memory, then from server memory to tape drives on the SAN.  Even though backups are quicker on the SAN, data still does not flow optimally between storage and backup devices because servers are involved. In addition to the performance bottleneck, managing data transfers during backups prevents servers from using their full resources on other important tasks, such as running applications and processing data.  As a result, although the backup window is not as tight as it was before the SAN, it still exists.  Backups must still be scheduled when they have the least impact on users and business processes running on the servers. Exabyte’s M2 tape drive eliminates these performance impediments by providing built-in serverless backup, a process by which data goes directly from disk to tape on the SAN, without traveling through a server. Serverless backup is sometimes called “extended copy” or “E-copy” because it is based on the SCSI Extended Copy command.  As shown in Figure 2, a server simply issues an Extended Copy command to the tape drive through its application software.  The command specifies the data’s location and how much is to be transferred.  The tape drive then assumes control of the actual data movement between disk and tape. With serverless backup, network administrators see significant cost-saving benefits above and beyond those already achieved through the SAN: Backups occur more quickly since server bottlenecks no longer exist. Dedicated backup servers can be eliminated. Application and file servers that double as backup servers can be made fully available for other business-critical tasks. Even though backups are quicker on the SAN, data does not flow optimally between storage and backup devices because servers are involved. p1   p2   p3   p4   p5   p6   p7   p8   p9   p10   p11   p12