Controller-to-stack cabling worksheet template for multipathed connectivity

By completing the worksheet template, you can define the controller SAS port pairs you can use to cable controllers to stacks of disk shelves with IOM12 modules to achieve multipathed connectivity in an HA pair configuration. You can also use the completed worksheet to walk yourself through cabling the multipathed connections for your configuration.

About this task

• This procedure and worksheet template is applicable to cabling multipathed connectivity for a multipath HA or multipath configuration with one or more stacks.

  Examples of completed worksheets are provided for multipath HA and multipath configurations.

  A configuration with two quad-port SAS HBAs and two stacks of disk shelves with IOM12 modules is used for the worksheet examples.

• The worksheet template allows for up to six stacks; you need to add more columns if needed.
• If needed, you can refer to the SAS cabling rules section for information about supported configurations, the controller slot numbering convention, shelf-to-shelf connectivity, and controller-to-shelf connectivity (including use of port pairs).
• If needed, after you complete the worksheet, you can refer to the How to read a worksheet to cable controller-to-stack connections for multipathed connectivity section.

1. In the boxes above the gray boxes, list all SAS A ports on your system, and then all SAS C ports on your system in sequence of slots (0,1, 2, 3, and so on).

   Example

   For example: 1a, 2a, 1c, 2c

2. In the gray boxes, list all SAS B ports on your system, and then all SAS D ports on your system in sequence of slots (0,1, 2, 3 and so on).

   Example

   For example: 1b, 2b, 1d, 2d
3. In the boxes below the gray boxes, rewrite the D and B port list so that the first port in the list is moved to the end of the list.

   Example

   For example: 2b, 1d, 2d, 1b
4. Circle (designate) a port pair for each stack.

   When all port pairs are being used to cable the stacks in your system, circle port pairs in the order in which they are defined (listed) in the worksheet.

   For example, in a multipath HA configuration with eight SAS ports and four stacks, port pair 1a/2b is cabled to stack 1, port pair 2a/1d is cabled to stack 2, port pair 1c/2d is cabled to stack3, and port pair 2c/1b is cabled to stack 4.

   
   
   
   When not all port pairs are needed to cable the stacks in your system, skip port pairs (use every other port pair).

   For example, in a multipath HA configuration with eight SAS ports and two stacks, port pair 1a/2b is cabled to stack 1 and port pair 1c/2d is cabled to stack 2. If two additional stacks are hot-added later, port pair 2a/1d is cabled to stack 3 and port pair 1c/2d is cabled to stack 4.

   Note

   When you have more port pairs than you need to cable the stacks in your system, the best practice is to skip port pairs to optimize the SAS ports on your system. By optimizing SAS ports, you optimize your system's performance.

   
   
   
   You can use your completed worksheet to cable your system.