Compaq Parallel Database Cluster Model PDC/O2000 for Oracle8i and Windows 2000 Administrator Guide

Cluster Architecture 2-27
Active/Active Configuration Examples for
Redundant Fibre Channel Fabrics
This section describes examples of active/active configurations when two,
three, four, and five RA4000/RA4100 Arrays are present in one redundant
Fibre Channel Fabric of a four-node PDC/O2000 cluster. These examples
represent one method for configuring active/active configurations. They are
presented here to provide a relatively simple and consistent method for
building active/active configurations for redundant Fibre Channel Fabrics.
IMPORTANT: Figures 2-11 through 2-14 show active/active configurations for a
four-node cluster. Active/active configurations for clusters with two, three, five, or more
nodes are not described here. However, the illustrated active/active configuration
examples provided should supply sufficient information for building an active/standby
configuration in any PDC/O2000 cluster.
The active/active configuration examples shown in Figures 2-11 through 2-14
follow these configuration guidelines:
■ For every Fibre Host Adapter pair, the top or leftmost Fibre Host
Adapter in each node is connected to the odd-numbered Fibre Channel
SAN Switch (Fibre Channel SAN Switch #1). This is an active Fibre
Host Adapter.
■ For every Fibre Host Adapter pair, the bottom or rightmost Fibre Host
Adapter in each node is connected to the even-numbered Fibre Channel
SAN Switch (Fibre Channel SAN Switch #2). This is also an active
Fibre Host Adapter.
■ In each RA4000/RA4100 Array, the top (rack model) or right rear
(tower model) array controller is always the active controller.
■ In each RA4000/RA4100 Array, the bottom (rack model) or left rear
(tower model) array controller is always the standby controller.
■ The odd-numbered Fibre Channel SAN Switch (Fibre Channel SAN
Switch #1) is connected to the active array controller in each
odd-numbered RA4000/RA4100 Array (1, 3, and 5).
■ The odd-numbered Fibre Channel SAN Switch (Fibre Channel SAN
Switch #2) is connected to the standby array controller in each
even-numbered RA4000/RA4100 Array (2 and 4).