Oracle DBA Interview Questions and Answers - RAC Oracle RAC Interview Questions and Answers How does starts first if voting disk & OCR resides in ASM Diskgroups? You might wonder how CSSD, which is required to start the clustered ASM instance, can be started if voting disks are stored in ASM? This sounds like a chicken-and-egg problem: without access to the voting disks there is no CSS, hence the node cannot join the cluster. But without being part of the cluster, CSSD cannot start the ASM instance. To solve this problem the ASM disk headers have new metadata in 11.2: you can use kfed to read the header of an ASM disk containing a voting disk. The kfdhdb.vfstart and kfdhdb.vfend fields tell CSS where to find the voting file. This does not require the ASM instance to be up. Once the voting disks are located, CSS can access them and joins the cluster. What is gsdctl in RAC? list gsdctl commands in Oracle RAC? GSDCTL stands for Global Service Daemon Control, we can use gsdctl commands to start, stop, and obtain the status of the GSD service on any platform. The for gsdctl are:- $ gsdctl start -- To start the GSD service $ gsdctl stop -- To stop the GSD service $ gsdctl stat -- To obtain the status of the GSD service Log file location for gsdctl: $ ORACLE_HOME/srvm/log/gsdaemon_node_name.log What is RAC? RAC stands for Real Application cluster. It is a clustering solution from Oracle Corporation that ensures high availability of databases by providing instance failover, media failover features. Oracle RAC is a cluster database with a shared cache architecture that overcomes the limitations of traditional shared-nothing and shared-disk approaches to provide a highly scalable and available database solution for all the business applications. Oracle RAC provides the foundation for enterprise grid computing. What is Oracle RAC One Node? Oracle RAC one Node is a single instance running on one node of the
Oracle DBA Interview Questions and Answers - RAC Oracle RAC Interview Questions and Answers How does starts first if voting disk & OCR resides in ASM Diskgroups? You might wonder how CSSD, which is required to start the clustered ASM instance, can be started if voting disks are stored in ASM? This sounds like a chicken-and-egg problem: without access to the voting disks there is no CSS, hence the node cannot join the cluster. But without being part of the cluster, CSSD cannot start the ASM instance. To solve this problem the ASM disk headers have new metadata in 11.2: you can use kfed to read the header of an ASM disk containing a voting disk. The kfdhdb.vfstart and kfdhdb.vfend fields tell CSS where to find the voting file. This does not require the ASM instance to be up. Once the voting disks are located, CSS can access them and joins the cluster. What is gsdctl in RAC? list gsdctl commands in Oracle RAC? GSDCTL stands for Global Service Daemon Control, we can use gsdctl commands to start, stop, and obtain the status of the GSD service on any platform. The for gsdctl are:- $ gsdctl start -- To start the GSD service $ gsdctl stop -- To stop the GSD service $ gsdctl stat -- To obtain the status of the GSD service Log file location for gsdctl: $ ORACLE_HOME/srvm/log/gsdaemon_node_name.log What is RAC? RAC stands for Real Application cluster. It is a clustering solution from Oracle Corporation that ensures high availability of databases by providing instance failover, media failover features. Oracle RAC is a cluster database with a shared cache architecture that overcomes the limitations of traditional shared-nothing and shared-disk approaches to provide a highly scalable and available database solution for all the business applications. Oracle RAC provides the foundation for enterprise grid computing. What is Oracle RAC One Node? Oracle RAC one Node is a single instance running on one node of the
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