ML6000 / PowerEdge, backup jobs and fiber connectivity

I have an environment comprised of an EMC CX4/120, a couple of clustered PowerEdge servers with fiber channel NICs, and a ML6000 tape library.  I am using Backup Exec 2010.  I have identified that the backup jobs are causing pretty severe application performance issues.  The problem is that when the backup job is running (using the Backup Exec Remote Agent), it gobbles up all of the bandwidth on the server and causes serious application latency issues for other servers that are trying to read from the server being backed up.

The clustered servers, ML6000, server running Backup Exec and SAN all have FC connectivity to each other.  I bring up the SAN because I am doing a file level backup of files on a SAN LUN that is presented to the server.

Is there any way to force the backup traffic onto the fiber and off of the ethernet network?  If that were possible, it would resolve my application latency issues.  I am not clear on how to configure it, or if such a configuration is even possible.