New features in Oracle RAC 12c Release 1/Release 2

Here are the new features in Oracle 12c Release 1/Release 2 RAC or Clusterware.

• Oracle Flex ASM - This feature of Oracle Clusterware 12c claims to reduce per-node overhead of using ASM instance. Now the instances can use remote node ASM for any planned/unplanned downtime. ASM metadata requests can be converted by non-local instance of ASM.
• Flex ASM supports larger LUNs (up to 32PB) and more number of diskgroups (up to 511).
• ASM Disk Scrubbing - From RAC 12c (Release 1), ASM comes with disk scrubbing feature so that logical corruptions can be discovered. Also Oracle 12c ASM can automatically correct this in normal or high redundancy diskgroups (e.g. alter diskgroup disk_group_name scrub repair).
• Oracle ASM Disk Resync & Rebalance enhancements.
• Multi-purpose Installation.
• Application Continuity (AC) - is transparent to the application and in case the database or the infrastructure is unavailable, these new features which work on JDBC drivers, mask recoverable outages. This recovers database session beneath the application so that the outage actually appears to be delayed connectivity or execution. Transaction guard (improvements of Fast Application Notification).
• All SRVCTL commands have been enhanced to accept full-word options instead of the single-letter options.
• Simulate commands without executing it.
  srvctl stop database -d devdb -eval;
  crsctl eval modify resource resource_name -attr value;
• IPv6 Support - Oracle RAC 12c now supports IPv6 for Client connectivity, Interconnect is still on IPv4.
• New SYSRAC administrative privileges for separation of duties - Oracle Database 12c provides a new administrative privilege for tasks related to Oracle Real Application Clusters (Oracle RAC) operations.
• Grid Home Server - we can have a single Golden Oracle Home on one of the nodes and all other nodes to be a client of that Golden Home. We have to patch the Golden Oracle Home and the rest will take it from there.
• Per Subnet multiple SCAN - RAC 12c, per-Subnet multiple SCAN can be configured per cluster.
• Shared Password file in ASM - password file in diskgroup will be used by all nodes.
• Each RAC instance opens the Container Database (CDB) as a whole so that versions would be the same for CDB as well as for all of the Pluggable Databases (PDBs). PDBs are also fully compatible with RAC.
• Oracle installer (OUI) will run root.sh script across nodes. We don't have to run the scripts manually on all RAC nodes.
• Oracle Utility Cluster.
• New "ghctl" command for patching.
• Oracle Clusterware uses the Diagnosability Framework and ADR for recording diagnostic trace data and the Clusterware alert log.
• TAF is extended to DML transactions failover (insert/update/delete).
• Grid Infrastructure software optionally creates Grid Infrastructure Management Repository (mgmtdb) database, which is available ONLY on one node, to assists in management operations.

[[ srvctl commands in Oracle RAC 12c ]]

Related Oracle Articles:  What's New in Oracle Database 12c