Compaq Infortrend manual Major Concerns

8.2Major Concerns

Most of the configuration options in this chapter are directly related to controller redundancy. Joining two controllers into a dual-active pair can eliminate most possible points of failure. Configuring a controller pair requires careful planning and proper setup and the requirements can be summarized as follows:

!Redundant Cache Coherency Channels (RCC):

1. RCC	FC channels can be manually assigned as
	the dedicated communications loops, two
	are recommended for path redundancy and
	sufficient bandwidth.

2.Drive + RCC Communications traffic distributed over drive loops

!Connection between Controllers:

Cabling between controllers, hardware link through a common backplane, Fibre hub or switch (for SAN applications and for those models that do not have by- pass chips)

!Channel Mode Assignment

According to the topological plan, your I/O channels can be designated as:

•Host

•RCC paths

•Drive

•Drive + RCC

!Host Channel Connection Type:

This depends on the way your RAID system is connected to the host computer(s). The host connection type can be:

•FC-AL

•Fabric (point-to-point)

!Controller Unique ID:

This ID will be used to generate Fibre ports’ node names, and is necessary for addressing the controller during the controller failover/failback operation.

!Dual-Loop:

1.Drive-sidedual loop provides data path redundancy. Firmware is capable of executing a load-sharing algorithm to optimize dual-loop

8-2 Infortrend