madhav_VM wrote:
Hi,
My understanding was iSCSI, FC, FCoE, NAS are the protocols used in VMware storage.
The first three are protocols, for so called block based storage. "Block" means that the storage array present a raw disk and accept low level SCSI commands against the physical blocks (sectors).
"NAS" is not a protocol, but a common name for file based storage. The file protocol supported by VMware is called NFS (version 3).
Then what is the relationship between iSCSI, FC, FCoE, NAS & SAN?.
In a few words: the first three are methods to carry SCSI commands over some kind of network.
iSCSI and FCoE uses Ethernet as carrier.
iSCSI uses TCP/IP on top of Ethernet, but FCoE does not.
FC means having specific Fibre Channel hardware (HBA cards, FC switches and FC controllers on the SAN) and uses the Fibre Channel Protocol (FCP) to carry SCSI commands over the FC network (called "fabric").
"NAS" is in VMware equalient to a server capable of presenting more or less a fileshare through the protocol NFS.
"SAN" is a common term for a device capable of presenting raw disks through a block protocol (FC, iSCSI, FCoE).