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How does Oracle RAC failover work?
Oracle RAC provides failover with the node VIP addresses by configuring multiple listeners on multiple nodes to manage client connection requests for the same database service. When a client issues a connection request using SCAN, the three SCAN addresses are returned to the client.
How does RAC scanning work?
Answer: SCAN provides a single domain name via DNS), allowing and-users to address a RAC cluster as-if it were a single IP address. SCAN works by replacing a hostname or IP list with virtual IP addresses (VIP). SCAN is part of the 11g release 2 movement toward “RAC Virtualization”.
What is LREG?
LREG (Listener Registration) is an Oracle background process created when you start an Oracle 12c or higher database instance. The Listener Registration process attempts register the information about the database instance and services if the listener is running.
Does SQL Developer use JDBC?
Database vendors offer JDBC drivers as free downloads. SQL Developer supports the following JDBC drivers. Microsoft SQL Server and Sybase:jTDS driver version 1.2. Download here.
What is ONS service in Oracle RAC?
Oracle Notification Service (ONS) allows for Oracle RAC to communicate the status for the nodes, which are typically UP and DOWN events, to the Oracle Universal Connection Pool (UCP). Distributed Transaction Processing (DTP) is a feature that was introduced in Oracle 10gR2.
What is fan in Oracle RAC?
Fast Application Notification (FAN) is a high availability notification mechanism that Oracle RAC uses to notify other processes about cluster configuration and service-level information, including status changes such as UP or DOWN events. FAN UP and DOWN events can apply to instances, services, and nodes.
How to connect to an Oracle RAC database using scans?
Oracle recommends that you configure Oracle RAC database clients to use the SCAN to connect to the database instead of configuring the tnsnames.ora file. Clients configured to connect to the cluster using node VIP addresses for Oracle RAC releases earlier than Oracle Database 11g Release 2 can continue to use their existing connection addresses.
Can you clone a RAC database to a standalone database?
Cloning from a RAC database to standalone database, can be done either using ACTIVE CLONE or by taking a RMAN backup from RAC database and restoring in standalone database.
Can a production RAC be converted to a non RAC?
Converting RAC instances to non-RAC instances temporarily, so the production DB can continue running while troubleshooting of RAC issues is in progress. In all cases, the Clusterware should be shutdown on other nodes to avoid conflicts of the operations.
What’s the default port identifier for Oracle RAC?
If you do not specify a port number, then the default value of 1521 is used for the TCP port identifier. The service_name is the name of a dynamic database service. The client then uses one of the returned SCAN VIP addresses to contact a SCAN listener.