Serial-attached SCSI (SAS) cables provide serial communication for transfer of data for directly attached devices, such as hard disk drives, solid-state drives, and CD-ROM drives.
Serial-attached SCSI (SAS) is an evolution of the parallel SCSI device interface into a serial point-to-point interface. SAS physical links are a set of four wires used as two differential signal pairs. One differential signal transmits in one direction while the other differential signal transmits in the opposite direction. Data might be transmitted in both directions simultaneously. SAS physical links are contained in ports. A port contains one or more SAS physical links. A port is a wide port if there are more than one SAS physical link in the port. Wide ports are designed to enhance performance and provide redundancy incase an individual SAS physical link fail.
There are two types of SAS connectors, mini SAS and mini SAS high density (HD). High density cables are typically needed to support 6 Gb/s SAS.
Each SAS cable contains four SAS physical links that are typically organized into either a single 4x SAS port or two 2x SAS ports. Each end of the cable uses a mini SAS or mini SAS HD 4x connector. Review the following design and installation criteria before installing your SAS cables:
The following table contains a list of the supported serial-attached SCSI (SAS) cable types and their designed usage.
Cable type | Function |
---|---|
AA cable | This cable is used to connect between the top ports on two tri-port SAS adapters in a RAID configuration. |
AI cable | This cable is used to connect from a SAS adapter to internal SAS disk slots that uses an FC 3650 or FC 3651 cable card, or by using an FC 3669 to the system external SAS port on your system. |
AE cable | These cables are used to connect a SAS adapter to a media expansion drawer. These cables can also be used to connect two SAS adapters to a disk expansion drawer in a unique JBOD configuration. |
AT cable | This cable is used with a PCIe 12X I/O drawer to connect from a PCIe SAS adapter to the internal SAS disk slots. |
EE cable | This cable is used to connect one disk expansion drawer to another in a cascaded configuration. Disk expansion drawers can only be cascaded one level deep, and only in certain configurations. |
YO cable | This cable is used to connect a SAS adapter to a disk expansion drawer. The cable must be routed along the right side of the rack frame (as viewed from the rear) when connecting to a disk expansion drawer. |
YI cable | This cable is used to connect a system external SAS port to a disk expansion drawer. The cable must be routed along the right side of the rack frame (as viewed from the rear) when connecting to a disk expansion drawer. |
X cable | This cable is used to connect two SAS adapters to a disk expansion drawer in a RAID configuration. The cable must be routed along the right side of the rack frame (as viewed from the rear) when connecting to a disk expansion drawer. |
The following table contains specific information about each supported SAS cable.
Name | Length | IBM® part number | Feature code |
---|---|---|---|
SAS 6x AA cable | 1.5 m (4.9 ft) | 74Y9029 | 5917 |
3 m (9.8 ft) | 74Y9030 | 5915 | |
6 m (19.6 ft) | 74Y9031 | 5916 | |
SAS 6x AT cable | 0.6 m (1.9 ft) | 74Y9035 | 3689 |
SAS 6x YO cable | 1.5 m (4.9 ft) | 74Y9036 | 3450 |
3 m (9.8 ft) | 74Y9037 | 3451 | |
6 m (19.6 ft) | 74Y9038 | 3452 | |
10 m (32.8 ft) | 74Y9039 | 3453 | |
15 m (49.2 ft) | 74Y9040 | 3457 | |
SAS 6x X cable | 3 m (9.8 ft) | 74Y9041 | 3454 |
6 m (19.6 ft) | 74Y9042 | 3455 | |
10 m (32.8 ft) | 74Y9043 | 3456 | |
15 m (49.2 ft) | 74Y9044 | 3458 | |
SAS 4x AI cable | 1 m (3.2 ft) | 44V4041 | 3679 |
SAS 4x AE cable | 3 m (9.8 ft) | 44V4163 | 3684 |
6 m (19.6 ft) | 44V4164 | 3685 | |
SAS 4x AT cable | 0.6 m (1.9 ft) | 44V5132 | 3688 |
SAS 4x EE cable | 1 m (3.2 ft) | 44V4147 | 3652 |
3 m (9.8 ft) | 44V4148 | 3653 | |
6 m (19.6 ft) | 44V4149 | 3654 | |
HD SAS 4x AT cable | 0.6 m (1.9 ft) | 74Y6260 | 3689 |
HD SAS AA cable | 0.6 m (1.9 ft) | 00J0094 | 5918 |
1.5 m (4.9 ft) | 74Y9029 | 5917 | |
3 m (9.8 ft) | 74Y9030 | 5915 | |
6 m (19.6 ft) | 74Y9031 | 5916 | |
HD SAS EX cable | 1.5 m (4.9 ft) | 00E5648 | 5926 |
3 m (9.8 ft) | 74Y9033 | 3675 | |
6 m (19.6 ft) | 74Y9034 | 3680 | |
HD SAS X cable | 3 m (9.8 ft) | 74Y9041 | 3454 |
6 m (19.6 ft) | 74Y9042 | 3455 | |
10 m (32.8 ft) | 74Y9043 | 3456 | |
HD SAS YO cable | 1.5 m (4.9 ft) | 74Y9036 | 3450 |
3 m (9.8 ft) | 74Y9037 | 3451 | |
6 m (19.6 ft) | 74Y9038 | 3452 | |
10 m (32.8 ft) | 74Y9039 | 3453 | |
SAS AA cable | 3 m (9.8 ft) | 44V8231 | 3681 |
6 m (19.6 ft) |
44V8230 |
3682 |
|
SAS YO cable | 1.5 m (4.9 ft) | 44V4157 | 3691 |
3 m (9.8 ft) | 44V4158 | 3692 | |
6 m (19.6 ft) | 44V4159 | 3693 | |
15 m (49.2 ft) | 44V4160 | 3694 | |
SAS YI cable | 1.5 m (4.9 ft) | 44V4161 | 3686 |
3 m (9.8 ft) | 44V4162 | 3687 | |
SAS X cable | 3 m (9.8 ft) | 44V4154 | 3661 |
6 m (19.6 ft) | 44V4155 | 3662 | |
15 m (49.2 ft) | 44V4156 | 3663 | |
Disk backplane to rear bulkhead, cascading. (internal cable) | 42R5751 | 3668 | |
Split disk backplane to rear bulkhead (internal cable) | 44V5252 | 3669 |
The following table contains cable label information. The graphic labels are designed to match the correct component port to which the cable end is to be attached.
Name | Connects | Label |
---|---|---|
SAS 6x AA cable |
Top connectors on tri-port SAS adapter to tri-port SAS adapter | |
SAS 6x AT cable |
PCIe SAS adapter in PCIe 12X I/O drawer to the internal SAS disk slots | |
SAS 6x YO cable |
SAS adapter | |
SAS 6x X cable |
Two SAS adapters to a disk expansion drawer in a RAID configuration | |
SAS 4x AE cable | SAS adapter to a media expansion drawer or two SAS adapters to a disk expansion drawer in a unique JBOD configuration | |
SAS 4x AI cable | SAS adapter to internal SAS disk slots to the system external SAS port on your system | |
SAS 4x AT cable | PCIe SAS adapter in PCIe 12X I/O drawer to the internal SAS disk slots | |
SAS 4x EE cable | One disk expansion drawer to another disk expansion drawer in a cascaded configuration | |
SAS AA cable |
Top connectors on tri-port SAS adapter to tri-port SAS adapter | |
SAS YO cable |
SAS adapter | |
SAS X cable |
Two SAS adapters to a disk expansion drawer in a RAID configuration | |
SAS YI cable | System external SAS port to a disk expansion drawer |
Figure 4, Figure 5, Figure 6, and Figure 7 illustrate connecting a SAS adapter to one, two, three, or four disk expansion drawers. It is also possible to connect three disk expansion drawers by omitting one of the cascaded drawers shown in Figure 6. Disk expansion drawers can be cascaded only one level deep.
When attaching only hard disk drives, it is also possible to cascade a second disk expansion drawer off of two out of the three drawers for a maximum of five disk expansion drawers per adapter. See Figure 6. Disk expansion drawers can be cascaded only one level deep.
Figure 11 illustrates connecting a SAS adapter to internal SAS disk slots through the system external SAS port.
Figure 13, Figure 14, Figure 15, and Figure 16 illustrate connecting two SAS adapters to one, two, or four disk expansion drawers in a RAID configuration. It is also possible to connect three disk expansion drawers by omitting one of the cascaded drawers shown in Figure 15. Disk expansion drawers can be cascaded only one level deep.
When attaching only hard disk drives, it is also possible to cascade a second disk expansion drawer off of two out of the three drawers for a maximum of five disk expansion drawers per adapter. See Figure 6.
Figure 17, Figure 18, and Figure 19 illustrate connecting two SAS RAID adapters with HD connectors to one, two, or three disk expansion drawers in a multi-initiator HA mode.
Figure 20 illustrates connecting two pair of SAS RAID adapters with HD connectors to one disk expansion drawer in a multi-initiator HA mode.
Figure 21 illustrates connecting two SAS adapters to a disk expansion drawer in a unique JBOD configuration.
There are several possible configurations for attaching PCIe SAS adapters to the internal SAS disk slots in the PCIe 12X I/O drawer, and multiple ways of setting up the disk layout within the drawer. The disk unit partitions switch setting on the rear of the PCIe 12X I/O drawer controls the grouping of the disk units within the drawer. This will also affect the way the adapter or adapters are cabled to specific ports on the PCIe 12X I/O drawer. The desired switch position should be selected before attaching the AT cables. If the disk unit partitions switch is changed, the PCIe 12X I/O drawer must be powered off and on for the new position to be detected.
All internal disk units are attached using AT cables. There are also options where other external expansion drawers might be connected to these same SAS adapters. External disk expansion drawers are attached using YO cables for single adapter configurations or X cables for two adapter configurations. External media expansion drawers are attached using AE cables for single adapter configurations. External media expansion drawers are not supported for two adapter configurations.
For complete details and examples of these configurations within the PCIe 12X I/O drawer, see Configuring the 5802 disk-drive subsystem. Figure 22 illustrates the rear view of a typical connection from two PCIe SAS adapters to the PCIe 12X I/O drawer. Use the AT cable to attach from an adapter port to a SAS port on the PCIe 12X I/O drawer.