Oracle RAC Classroom Training and Certification Classes

The Clusterware is installed on each node (on an Oracle Home) and on the shared disks (the voting disks and the CSR file)

OCFS, ASM, Raw devices and Third party cluster file system such as GPFS or Veritas

The Cluster Verification Utility (CVU) is a validation tool. It is used to verify all the major components at different stages of deployment in an RAC environment.

• Cluster Interconnect (HAIP)
• Shared Storage (OCR/Voting Disk)
• Clusterware software

Clusterware is software that provides various interfaces and services for a cluster. It capabilities include:

• Allow the cluster to be managed as a whole
• Protect the integrity of the cluster
• Maintain a registry of resources across the cluster
• Deal with changes to the cluster
• Provide a common view of resources

GNS stands for Grid Naming service which is an alternative service to DNS. It acts as a sub domain in DNS but is managed by Oracle. With GNS the connection is routed to the cluster IP and manages internally.

In a RAC environment, it is the combining of data blocks to complete the requirements for a transaction (DML, Query of Data Dictionary). The data blocks are shipped across the interconnect from remote database caches to the local node.

When database nodes in a cluster are unable to communicate with each other, they may continue to process and modify the data blocks independently. If the same block is modified by more than one instance, synchronization/locking of the data blocks does not take place and blocks may be overwritten by others in the cluster. This state is called split brain.

It is used to ship data blocks from one instance to another for cache fusion.

Configuring Network Time Protocol (NTP) or using Cluster Time Synchronization Service (CTSS)

Spfiles, ControlFiles, Datafiles and Redolog files should be created on shared storage.

All processing will show down to the CPU speed of the slowest server.

Datafiles, Redo logfiles and Spfiles

• CLUSTER_DATABASE
• CLUSTER_DATABASE_INSTANCE
• INSTANCE_TYPE (RDBMS or ASM)
• ACTIVE_INSTANCE_COUNT
• UNDO_MANAGEMENT

OLR, OCR and ASM Metadata