Is it Mandatory to have a SAN switch to get LAN-FREE Backups using NetBackup in VMWare environement?

There is an IBM DS3524 FC storage (i.e. four FC ports per controller; all together 8 ports) and THREE ESXi hosts are attached directly utilizing six out of eight FC ports in the storage.

We want to have LAN-FREE backups of VMs using Symantec NetBackup.

Is it necessary to have a SAN switch in order to have LAN-FREE backups of the VMs? If so, why is that?

Can't we utilized the remaining two FC ports of the storage to connect to the Backup Media Server where NetBackup is running and trigger LAN-FREE backups from there? Note that the Tape library is directly attached to the Back Media Server uning SAS.

Please advice.

Thanks