Oracle Load Balancing RAC

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In Oracle RAC we have 2 types of listeners 

Remote Listener 

Local Listener 

Remote Listener always updated with scan IP and local listener with Local VIP of the instance. When ever user process makes a connection request to the scan listener it uses LBA(load Balance Advisory ) to redirect the connection to the  local listener of the least node of the cluster in Round Robin fashion.

Oracle Load balancing is of 2 types 

client side and server side 

Client-side load balancing balances the connection requests across the listeners. With server-side load balancing

server-side load balancing, the SCAN listener directs a connection request to the best instance currently providing the service by using the load balancing advisory.

Note: In Oracle RAC the default  connection is dedicated connection , however we can specify shared connection during DBCA configuration




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