Refers to backing up data without transferring it across the LAN or WAN and slowing down the network. The simplest LAN free architecture is a server or a NAS storage device with backup storage (tapes, MO, CD, etc.) directly attached. A common approach is to use a SAN that connects the disks and backup storage via a Fibre Channel switch. The backup operation is managed by a backup server.|
A variation of LAN free is "serverless backup." Serverless backup uses a SAN, but instead of having a backup server manage the backup operation, it uses a simpler device called a "data mover." The data mover can be embedded into the backup storage device itself or be a separate unit that also handles conversion from Fibre Channel to SCSI. See backup.
In small companies, it is very common to back up data over the LAN. However, if this is done during work hours, response times for users are severely degraded.
If servers and NAS storage devices are connected directly to backup storage, the LAN itself is not impacted, but the servers and NAS devices are. They have to perform backup operations and serve users at the same time.
A SAN provides a high-speed solution for backing up data. Fibre Channel connections between disks and backup storage are very fast. Data are often staged in separate areas on disk beforehand, so that users and backup are not working on the same data at the same time.
Serverless is an extension of the LAN free. It uses a SAN, but instead of a backup server to manage the operation, serverless uses a "data mover," which is a simpler device that can be embedded into the backup storage itself. The backup server initiates the backup, and the data mover manages it.
ATTO Technology's FibreBridge manages the backup operation and provides FC to SCSI conversion. ATTO sells board versions of the FibreBridge to backup manufacturers that embed the functionality in their storage products. (Image courtesy of ATTO Technology, Inc., www.attotech.com)