In the Direct SAN mode, VM data is retrieved directly from Fiber Channel/iSCSI shared storage (Storage Area Network, or SAN) using the VMware vStorage API for Data Protection.
The process of data retrieval in Direct SAN Access mode includes the following steps:
1.The backup proxy sends a request to the ESX host to locate the necessary VM on the datastore.
2.The host locates the VM and retrieves metadata about the layout of virtual disks on SAN, or the physical addresses of data blocks
|3, 4||The host sends the metadata to the backup proxy.|
5.The backup proxy uses this metadata to copy data blocks directly from SAN.
6.The backup proxy sends data copied from the datastore to the target.
The SAN mode uses metadata on the layout of virtual disks on SAN to directly read data blocks off SAN LUN, therefore providing LAN-free transfer of VM data.
VM processing will fail if direct SAN connection is not configured or not available when the job starts.