In NAS and SANs, are there any "devices" or servers that sit between a client and the actual storage device? Is there any situation in which the fabric or servers actually govern access to the storage devices?
A NAS solution always has some type of processor that sits between the client that is making file requests and the actual disk drives that performs block operations. A NAS solution can be:
- An appliance that includes a processor (Intel, AMD, Broadcom, etc.) running the NAS software and integrated disk drives.
- A general purpose server running NAS software with disk drives attached.
- A gateway.
- A NAS head attached to external storage. A NAS head is essentially a processor and NAS software without any disk drives that attaches to shared or dedicated external storage devices. For example a NAS head could attach to SAN attached storage.
Some NAS appliances as well as general purpose servers running NAS software can also support SAN attached storage for additional capacity.
This was first published in October 2004