Skip to main content
Install and maintain

Controller-to-stack cabling worksheet template for quad-pathed connectivity - shelves with IOM1/IOM12B2 modules

Contributors
PDFs

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/IOM12B modules to achieve quad-pathed connectivity in an HA pair or single-controller configuration. You can also use the completed worksheet to walk yourself through cabling the quad-pathed connections for your configuration.

About his task

  • This procedure and worksheet template is applicable to cabling quad-pathed connectivity for a quad-path HA or quad-path configuration with one or more stacks.

    Examples of completed worksheets are provided for quad-path HA and quad-path configurations.

    A configuration with two quad-port SAS HBAs and two stacks of disk shelves with IOM12/IOM12B modules is used for the worksheet examples.

  • The worksheet template allows for up to two stacks; you need to add more columns if needed.

  • Quad-pathed connectivity for controller-to-stack connections consists of two sets of multipathed cabling: the first set of cabling is referred to as “multipathed”; the second set of cabling is referred to as “quad-pathed”.

    The second set of cabling is referred to as “quad-pathed” because completing this set of cabling gives you the quad-pathed connectivity from a controller to a stack in an HA pair or single-controller configuration.

  • Disk shelf IOM ports 1 and 3 are always used for multipathed cabling and IOM ports 2 and 4 are always used for quad-pathed cabling, as designated by the worksheet column headings.

  • In the worksheet examples, port pairs are designated for multipathed cabling or quad-pathed cabling to the applicable stack.

    Each port pair designated for multipathed cabling is encircled by an oval that is the color associated with the stack it is cabled to. Each port pair designated for quad-pathed cabling is encircled by a rectangle that is the color associated with the stack it is cabled to. Stack 1 is associated with the color blue; stack 2 is associated with the color orange.

  • If needed, you can refer to SAS cabling rules and concepts for information about the controller slot numbering convention, shelf-to-shelf connectivity, and controller-to-shelf connectivity (including the use of port pairs).

  • If needed, after you complete the worksheet, you can refer to How to read a worksheet to cable controller-to-stack connections for quad-pathed connectivity.

drw worksheet quad pathed template nau
Steps

  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).

    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).

    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.

    For example: 2b, 1d, 2d, 1b

  4. Identify the two sets of port pairs to connect to stack 1 by drawing an oval around the first set of port pairs and a rectangle around the second set of port pairs.

    Both sets of cabling are needed to achieve quad-pathed connectivity from each controller to stack 1 in your HA pair or single-controller configuration.

    The following example uses port pair 1a/2b for the multipathed cabling and port pair 2a/1d for the quad-pathed cabling to stack 1.

    drw worksheet qpha slots 1 and 2 two 4porthbas two stacks set1 circled nau

  5. Identify the two sets of port pairs to connect to stack 2 by drawing an oval around the first set of port pairs and a rectangle around the second set of port pairs.

    Both sets of cabling are needed to achieve quad-pathed connectivity from each controller to stack 1 in your HA pair or single-controller configuration.

    The following example uses port pair 1c/2d for the multipathed cabling and port pair 2c/1b for the quad-pathed cabling to stack 2.

    drw worksheet qpha slots 1 and 2 two 4porthbas two stacks nau

  6. If you have a quad-path (single-controller) configuration, cross out the information for controller 2; you only need controller 1 information to cable the controller-to-stack connections.

    The following example shows that the information for controller 2 is crossed out.

    drw worksheet qp slots 1 and 2 two 4porthbas two stacks nau