What's a SNIC?
By kgibson on Apr 25, 2005
A SNIC is a Storage Network Interface Card. It's how you connect a compute server to the storage network.
Direct-attached storage is connected to compute servers through Host Bus Adapters (HBAs), so called, because they adapt one bus to another. Servers have an internal bus, such as PCI, designed with one set of characteristics - short distance, word addressible, short quick data bursts, etc. On the other hand, external storage busses such as SCSI are designed for longer cable lengths, longer bursts of streamed data, etc. The HBA adapts the characteristics of the external storage bus to the internal one.
Now, go to many of today's large data centers that have over a hundred individual storage devices connected by a complex network with over a thousand ports, dozens of switches and miles of FC or ether network cabling. These are true networks running network protocols. How do you connect compute servers/data clients to these networks? With a SNIC. What else?