A Little About SCSI

• SCSI defines a BUS-based protocol - you connect several devices to a BUS, give a unique ID to each device, and allow them to communicate.
• On the server (host) you install an HBA (Host-BUS Adapter) to communicate with the SCSI BUS.
• A SCSI address is composed of 4 numbers:
  1. Host number (the number of the SCSI HBA on the host)
  2. Port (or channel) - in case an HBA has more then one SCSI port
  3. Target ID (identifies a storage controller)
  4. LUN (Logical Unit Number) - identifies a single SCSI disk/tape/whatever in a given target.

Originally written by guy keren