NonStop NS14000 Series Planning Guide (H06.13+)

Figure 18 Sixteen Fibre Channel Ports, Eight FCDMs, Two VIO Enclosures

Daisy-Chain Configurations

When planning for possible use of daisy-chained disks, consider:

Requirements for Daisy-Chain

Daisy-Chained Disks Not

Recommended

Daisy-Chained Disks Recommended

All daisy-chained Fibre Channel disk

modules reside in the same cabinet and

are physically grouped together.

Many volumes in a large Fibre

Channel loop. The more volumes that

exist in a larger loop, the higher the

Cost-sensitive storage and applications

using low-bandwidth disk I/O.

potential for negative impact from a

failure that takes down a Fibre

Channel loop.

ID expander harness with terminators

is installed for proper Fibre Channel

disk module and drive identification.

Applications with a highly mixed

workload, such as transaction data

bases or applications with high disk

I/O.

Low-cost, high-capacity data storage

is important.

Fibre Channel ports for each Fibre

Channel loop are installed in a different

VIO enclosure for fault tolerance.

Two Fibre Channel disk modules

minimum, with four Fibre Channel disk

modules maximum per daisy chain.

80 System Configuration Guidelines