Converting an Oracle 12c Clusterware Standard Cluster to an Oracle Flex Cluster

The following is a summarized procedure in how to convert from Oracle 12c standard Cluster to Oracle New Flex cluster.

 

  1. Execute the following command to check your current cluster mode:

crsctl get cluster mode status

    cluster is running in “standard” mode

  1. Run the command to check that GNS is configured with fixed IP:

srvctl config gns

** if GNS  is not configured then you need to do so by executing the following command as “root” after making sure that GNS IP entry is added in DNS server:

srvctl add gns -vip vipname | ip_address

                 srvctl start gns

 

  1. Set the mode of the cluster to “flex” by executing the below command as “root”:

crsctl set cluster mode flex

Cluster mode set to “flex”

 

  1. Stop/Start the cluster so the new mode takes affect:

 crsctl stop crs

                   crsctl start crs

Status of cluster mode is “FLEX”

 

Important Final Remarks:

  • The cluster conversion is one direction from standard===> Flex  ONLY.

 

  • GNS is required with fixed IP address for Flex setup.

 

  • Oracle Flex cluster works ONLY with Oracle Flex ASM, while Oracle Flex ASM can work with either standard or Flex cluster.

 

                   Oracle Flex Cluster Architecture

 

oracle-flex-architecture