I have a question regarding Hitachi's new NAS product that can support both NAS and SAN functionality by partitioning a portion of the storage capacity to NAS. Please refer to the following link for more detail:
Can you please explain to me all the possible network topologies of how this new system will be implemented? I do not quite understand how this device can both support NAS and SAN at the same time when a NAS is connected directly on a LAN, while a SAN has its own entire LAN built specifically for the SAN. If you can please draw the topology on a piece of paper and then scan all the possible network topologies supporting this new Hitachi product.
In this case, the NAS is really a NAS "head" or "gateway" or "controller" depending on which vendor's terminology you use. I tend to like the "NAS gateway" designation the best since it is the most descriptive. The NAS gateway performs all of the NAS functions and accesses its data in block mode over a standard interface such as Fibre Channel. All NAS devices access data in block mode over a standard interface to devices, the only difference is that in this case, the device is external and may be resource shared for other purposes. The resource sharing means that specific LUNs (logical units) of the storage system will be dedicated to the NAS gateway for use while others may be used for other purposes such as server attached storage, either directly or through a Storage Area Network. From the NAS gateway standpoint, it doesn't know anything about the other resources (LUNs in the storage system). The front end of the NAS gateway is still connected to the LAN, but the backend (the storage side) is what would be connected to a storage system (either directly or through a SAN).
Hopefully, this is straight forward enough that you can draw the picture.
Evaluator Group, Inc.
This was first published in June 2001