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

Cluster Software Components 3-5
Compaq Confidential – Need to Know Required
Writer: John Blackburn Project: Compaq Parallel Database Cluster Model PDC/O2000 for Oracle8i and Windows 2000 Comments:
Part Number: 225082-002 File Name: d-ch3 Cluster Software Components.doc Last Saved On: 6/13/01 10:24 AM
Compaq StorageWorks Secure Path
for Windows 2000
Compaq StorageWorks Secure Path for Windows 2000 (Secure Path) must be
installed on each server (node) in the PDC/O2000. Secure Path monitors all
I/O paths to the storagesets in the shared storage subsystems. If any
component along an active I/O path fails, Secure Path detects this failure and
automatically reroutes I/O activity through the defined backup path. Failovers
are transparent and non-disruptive to applications.
Secure Path Manager is the client application used to manage multiple path
StorageWorks RAID array configurations. Secure Path Manager displays a
graphical presentation of the current multiple I/O path environment and
indicates the location and state of all configured storage units on each path. To
facilitate load balancing, Secure Path Manager provides the capability to move
storagesets from their configured paths to other paths during normal cluster
operation. Secure Path Manager can be run locally at the cluster nodes or
remotely at a management station.
Compaq Operating System Dependent Modules
Compaq supplies low-level services, called operating system dependent
modules (OSDs), which are required by Oracle8i Parallel Server. The OSD
layer monitors critical clustering hardware components, constantly relaying
cluster state information to Oracle8i Parallel Server. Oracle8i Parallel Server
monitors this information and takes pertinent action as needed.
For example, the OSD layer is responsible for monitoring the cluster
interconnect of each node in the cluster. The OSD layer determines if one of
the nodes is no longer responding to the cluster heartbeat. If the node still does
not respond, the OSD layer determines it is unavailable. The OSD layer evicts
the node from the cluster and informs Oracle8i Parallel Server. Oracle8i
Parallel Server recovers the part of the database affected by that node, and
reconfigures the cluster with the remaining nodes.
OSDs for Oracle8i Parallel Server
For a detailed description of how the OSD layer interacts with Oracle8i
Parallel Server, refer to the Oracle8i Parallel Server Setup and Configuration
Guide.
The OSD software is found on the Compaq Parallel Database Cluster
Clustering Software for Oracle8i on Microsoft Windows 2000 CD. This CD is
supplied in the cluster kit for the Compaq Parallel Database Cluster Model
PDC/O2000 for Windows 2000.