RAC architecture concepts

Oracle Real Application clusters (RAC) allows multiple instances to access a single Oracle database. These instances often run on multiple nodes. The Component Diagram with explanation shows all the components that inter-relate to each other and together make up THE “Oracle RAC architecture“.   RAC is the principal component for the Oracle Grid Architecture. It’s […]

Resource is in UNKNOWN state and srvctl Cannot Start/Stop the Resource

An Oracle RAC Service is in UNKNOWN state on instance 1 and it is impossible to stop or start it with srvctl. crs_stat -u ora.DBName.My-ServiceName.DBName1.srv NAME=ora.DBName.My-ServiceName.DBName1.srv TYPE=application TARGET=ONLINE STATE=UNKNOWN on Host1   Solution: The UNKNOWN state can often be resolved by bringing the resource offline using crs_stop. If the resource is not in Unknown state: Use […]

Useful Oracle RAC Commands

Download Brave : Secure, Fast & Private Browser with Adblocker Here is a FAQ and examples of useful Oracle RAC Commands I use for the administration of Oracle 19c, 18c and 12c Reak Application Cluster: 1- Shutdown and Start sequence steps of Oracle RAC components 2- Manage low level cluster resources: CRS, HAS, cluster 3- […]