VERITAS Storage Foundation 4.1 for Oracle RAC HP Serviceguard Storage Management Suite Extracts, December 2005

Storage Foundation for Oracle RAC Overview
Storage Foundation for Oracle RAC Overview
Storage Foundation for Oracle RAC provides a complete I/O and communications stack to
support Oracle RAC. This software also monitors and manages the startup and shutdown
of instances. The following section describes the overall data and communications flow of
the Storage Foundation for Oracle RAC stack.
Data Stack Overview
Oracle
RAC
Instance
Oracle
RAC
Instance
LGWR
ARCH
CKPT
DBWR
ODM ODM
CFSCFS
CVM CVM
Redo
Log
Files
Archive
Storage
Data
and
Control
Files
Disk I/O Disk I/O
LGWR
ARCH
CKPT
DBWR
The diagram above details the overall data flow from an instance running on a server to
the shared storage. The various Oracle processes making up an instance (such as DB
Writer, Log Writer, Checkpoint, and Archiver) read and write data to storage via the I/O
stack shown in the diagram. Oracle communicates via the Oracle Disk Manager (ODM)
interface to the VERITAS Cluster File System (CFS), which in turn accesses the storage via
the VERITAS Cluster Volume Manager (CVM). Each of these components in the data stack
is described in this chapter.
4 VERITAS Storage Foundation for Oracle RAC Installation and Configuration Guide