Lenovo DM120S, Installation And Cabling Manual, Page: 53 / 70

Chapter 10. Controller-to-stack cabling worksheet template
for quad-pathed 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 quad-pathed connectivity in an HA pair
configuration. You can also use the completed worksheet to walk yourself through cabling the quad-pathed
connections for your configuration.
About this 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 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 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 the “SAS cabling rules” section 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 the “How to read a worksheet to cable
controller-to-stack connections for quad-pathed connectivity” section.
Step 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
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