Chapter 9. MetroCluster expansion cabling  133
About these procedures
The following general information applies to the procedures that are described in this IBM 
RedbooksÂŽ publication:
ň° The use of SAS optical cables in a stack that is attached to FibreBridge 6500N bridges is 
not supported.
ň° Disk shelves that are connected with SAS optical cables require a version of disk shelf 
firmware that supports SAS optical cables. Best practice is to update all disk shelves in the 
storage system with the latest version of disk shelf firmware.
ň° The cable QSFP connector end connects to a disk shelf or a SAS port on a controller.
ň° The QSFP connectors are keyed; when oriented correctly into a SAS port, the QSFP 
connector clicks into place and the disk shelf SAS port link LED, labeled LNK (Link 
Activity), illuminates green. Do not force a connector into a port.
ň° The terms node and controller are used interchangeably.
9.2.2  Installing a new system with SAS disk shelves by using SAS optical 
cables
You can install a new system that has SAS disk shelves by using all SAS optical cables for 
shelf-to-shelf, controller-to-shelf, controller-to-patch panel, and patch panel-to-shelf 
connections.
Before you begin
The following prerequisites must be met before you begin:
ň° You ordered and received the appropriate type, number, and length of SAS optical cables 
that are required for your configuration.
ň° Your system must have the appropriate number of available SAS ports on each controller. 
If you are using SAS HBAs, your system must have the appropriate number of supported 
SAS HBAs installed.
ň° You must determine the controller SAS ports that you are cabling by completing the SAS 
cabling worksheet in the Universal SAS and ACP Cabling Guide.
ň° You must check the Interoperability Matrix Tool to verify that your system meets all 
configuration requirements for the SAS optical cable.
ň° You must check the Data ONTAP High Availability and MetroCluster Configuration Guide 
for 7-Mode to verify that your system meets all of the applicable stretch MetroCluster 
requirements as defined in the MetroCluster installation section.
Steps
Complete the following steps from either node:
1. Properly ground yourself.
2. Install the platforms.
For more information about installing the platforms, see the Installation and Setup 
Instructions that came with your platform.
Note: Do not revert disk shelf firmware to a version that does not support SAS optical 
cables.