Using Serviceguard Extension for RAC, 5th Edition, June 2007

Introduction to Serviceguard Extension for RAC
Serviceguard Extension for RAC Architecture
Chapter 120
Serviceguard Extension for RAC Architecture
This chapter discusses the main software components used by
Serviceguard Extension for RAC in some detail. The components are:
• Oracle Components
— Custom Oracle Database
• Serviceguard Extension for RAC Components
— Group Membership Services (RAC)
• Serviceguard Components
— Package Manager
—Cluster Manager
— Network Manager
•Operating System
— Volume Manager Software
—HP-UX Kernel
Group Membership Daemon
In addition to the Serviceguard daemon processes mentioned in Chapter
3 of the Managing Serviceguard user’s guide, there is another daemon
that is used by Oracle to enable communication with Serviceguard
Extension for RAC:
• cmgmsd—Group Membership Daemon for RAC 9i or later
This HP daemon provides group membership services for Oracle Real
Application Cluster 9i or later. Group membership allows multiple
Oracle instances to run on the same cluster node. GMS is illustrated in
Figure 1-2 on page 18.