User`s guide

Appendix A: Introduction to Serial Attached SCSI (SAS) ● 75
What do SAS Cables Look Like?
Internal SAS cables are narrower than internal parallel SCSI cables. The
connectors vary in size depending on the number of links they support,
from single link connectors to 4-wide (or larger) connectors. Internal
fan-out cables (shown below) let you attach four disk drives to a single
4-wide connector.
An example of some internal SAS cables and an external SAS cable are
shown in the figure above.
How are Disk Drives Identified in SAS?
In the BIOS and in the management utilities (see page 60), disk drives
are identified with numbers in this format:
XX:YY:ZZ
where XX is the disk drive count number, YY is the enclosure number,
and ZZ is the slot number (within the enclosure). If the disk drive is not
installed in an enclosure, a double dashes (--) appear instead of YY and
ZZ (for instance, 01:--:--).
In parallel SCSI, XX is the disk drive’s channel number, YY is the target
number, and ZZ is the logical unit number (LUN).
4x wide-to-4x wide
internal SAS cable
Internal SAS-to-SATA fan-out cable
(SAS-to-SAS fan-out cables are
also available)
External SAS cable