What is Oracle RAC architecture?
The Oracle RAC option with Oracle Database enables you to cluster Oracle databases. Oracle RAC uses Oracle Clusterware for the infrastructure to bind multiple servers so they operate as a single system. Oracle Clusterware is a portable cluster management solution that is integrated with Oracle Database.
How does Oracle RAC work?
Oracle Real Application Clusters (RAC) allow customers to run a single Oracle Database across multiple servers in order to maximize availability and enable horizontal scalability, while accessing shared storage.
What are Oracle RAC components?
Oracle RAC consist of three components: The Oracle clusterware software (CRS) Software to create and manages the communication between the cluster of nodes. The relational database (RDBMS)
What is RAC configuration?
Oracle Real Application Cluster (RAC) is a “share-everything” database architecture that can provide high availability and load balancing. A typical configuration for an Oracle RAC contains two or more Oracle RAC nodes that are clustered together and share the same storage.
What are the background processes in Oracle RAC?
In an Oracle RAC environment, the ACMS per-instance process is an agent that contributes to ensuring a distributed SGA memory update is either globally committed on success or globally aborted if a failure occurs.
What is CSSD and Crsd in Oracle RAC?
Oracle Cluster Synchronization Services daemon (CSSD) Cluster Ready Services daemon (CRSD), which is the main engine for maintaining availability of resources. Event Manager daemon (EVMD)
What are the four main daemons in RAC?
This includes start, stop, monitor, and failover operations. The crsd process generates events when the status of a resource changes.
What is Oracle RAC vs grid?
Thus, RAC is an integral part of Grid computing, but it is not the sum total of it. The goal of Grid computing is to supply high availability information sharing supported by an architecture with sufficient resource allocation such that users can rely on getting as much information or processing as they need on demand.
What is RAC startup sequence?
1) INIT : INIT is the very first file to be checked to be start at the time of the operating system boot,it is system and service manager for the Linux , Aix or any other Linux flavor. This service start and stop through script which is stored in the /etc/init. d directory .
What is Nodeapps in Oracle RAC?
Nodeapps are a standard set of Oracle application services that are automatically launched for RAC (Real Application Cluster). The following service are lunched by nodeapps: •Virtual IP (VIP) •Oracle Net Listener. •Global Services Daemon (GSD)
What is CSSD in RAC?
Oracle Cluster Synchronization Services daemon (CSSD)
What is a node in Oracle RAC?
Oracle Real Application Clusters (RAC) One Node is an option to the Oracle Database Enterprise. Edition that was introduced with Oracle Database 11g Release 2. It provides enhanced high availability. for single instance Oracle Databases, protecting them from both, planned and unplanned downtime.
What is Private IP in Oracle RAC?
Private IP addresses are required by Oracle RAC to provide communication between the cluster nodes. Depending on your private network configuration, you may need one or more IP addresses. You can configure the private IP addresses for high availability using the PrivNIC or MultiPrivNIC agents.
Can I configure Oracle RAC on a single database cluster?
However, you can configure Oracle RAC on an Oracle Extended Cluster, which is an architecture that provides extremely fast recovery from a site failure and allows for all nodes, at all sites, to actively process transactions as part of a single database cluster.
What are Oracle RAC processes and their identifiers?
The Oracle RAC processes and their identifiers are as follows: In an Oracle RAC environment, the ACMS per-instance process is an agent that contributes to ensuring a distributed SGA memory update is either globally committed on success or globally aborted if a failure occurs.
What are service performance rules in Oracle RAC?
In Oracle RAC databases, the service performance rules that you configure control the amount of work that Oracle Database allocates to each available instance for that service. As you extend your database by adding nodes, applications, components of applications, and so on, you can add more services.
What is the Oracle RAC infrastructure?
The Oracle RAC infrastructure is also a key component for implementing the Oracle enterprise grid computing architecture. Having multiple instances access a single database prevents the server from being a single point of failure.