Sample Configuration with HP Serviceguard Extension for RAG and Oracle Real Application Clusters 11g release 2 using Cluster File System

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Capacity planning
Proper capacity planning helps ensure that sufficient resources are available to meet expected service
levels.
Processor capacity
In a cluster environment, cluster members maintain heartbeat traffic between nodes. Insufficient CPU
processing capacity affects application performance. A longer timeout means it takes longer to
reconfigure a cluster, and more time is needed before a node failure or network failure can be
detected.
Memory
Sufficient physical memory should be available for all processes. Insufficient memory may result in
swapping activities that affect CPU availability to components that have timed heartbeat
communications. In general, your systems should have enough memory to reduce paging activities, fit
the Oracle System Global Area (SGA) into the main memory, and allow for user processes.
Network: clients
Insufficient bandwidth on the client network limits availability to the client.
Network: cluster interconnect
Insufficient bandwidth from the cluster interconnect slows communication between cluster components.
Storage
Sufficient storage bandwidth and storage space are required to maintain optimal database service.
Adequate space should also be allocated to database archives for recovery purposes.
Failover time requirements
In a RAC configuration with SGeRAC, each node or can have concurrent access to the database. The
database service is accessible from all nodes, and each node provides a client connection endpoint
(IP address, port, and listener). When one node fails, clients can connect to another node for services.
The client connection endpoint does not need to fail-over for clients to have continued service.
However, even with an alternate connection endpoint available, for some failures—for example, node
or network failures—new client connections may not connect, or the database service may be
unavailable, until the cluster goes through reconfiguration and/or recovery.
The failover time is the time from when a failure occurs to when the service is once again available to
the client. A failover time requirement is important because of its effect on these processes:
How fast the clients reconnect:
• For a local LAN failover, client reconnection speed depends on how long it takes to detect the
failover, and on the local LAN failover scheme.
• For a failover to another node, client reconnection speed depends on whether clients are enabled
with Oracle Fast Application Notification (FAN), how fast cluster reconfiguration happens, how
soon the Virtual IP Address (VIP) address fails-over, and how soon the client connection times out.
How fast the cluster and RAC go through reconfiguration before database service resumes:
• For a node failure, the reconfiguration time depends on the SG
MEMBER_TIMEOUT setting, the
number of nodes, and the type of quorum device used.
• For cluster network interconnect failures, database service availability depends on how soon the
Real Application Cluster Interconnect traffic for both Global Cache Service and Global Enqueue