Oracle SG-XPCIESAS-R-INT-Z, Installation Manual

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Appendix G Introduction to Serial Attached SCSI 107
About SAS Connectors
A SAS or mini-SAS connector is the physical plug or receptacle that you see on a SAS
device. It’s what you plug a SAS cable into, or the end of the SAS cable that’s being
plugged in. (See
“Preparing for Hardware Installation” on page 10 .)
A connector is what forms physical links between phys. Some SAS connectors can
support multiple links. The number of links a SAS connector can support is referred
to as its
width . Narrow connectors support a single link; wide connectors supports
more than 1 link.
A single SAS device may have one or more connectors. A single SAS connector may
help form links between more than two SAS devices. (For instance, as shown in
FIGURE 2-6
, the 4-wide internal SAS connector forms links with four independent disk
drives.)
About SAS Cables
Internal standard 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 let you attach four disk drives
to a single 4-wide connector.
Mini-SAS connectors support both internal and external SAS connections. The mini-
SAS connectors are smaller than the standard SAS internal and external connectors.
Mini-SAS connectors support single and multilinks with the ability to scale to future
speed needs.
About Identifying Disk Drives in SAS
In the BIOS and in the management utilities (see “To Identify Disk Drives With the
Disk Utilities” on page 77 ), disk drives are identified in the following formats:
■
CNX:DevY = Device Y is attached to Connector X (see “Direct-Attach
Connections” on page 108 below for more information)
■
BoxX:SlotX = Enclosure X is attached to a disk drive in Slot X (see “Backplane
Connections” on page 108 below for more information)