🧩 ORA-07445 in RAC Environments

🧩 Introduction

ORA-07445 can appear in Oracle RAC (Real Application Clusters) environments when a process encounters a low-level exception, such as an access violation, on one of the cluster nodes. These errors may affect a single session or multiple nodes, impacting application availability. Understanding ORA-07445 in RAC is critical for DBAs managing high-availability systems.

Error Message Example:

ORA-07445: exception encountered: core dump [sigsegv] [addr:0x000000] [pc:0xabcdef]

The alert log often indicates the node and process affected.

Common Causes in RAC

Bugs in Oracle RAC inter-node communication.

Corruption in shared data or cache fusion.

Problematic SQL or PL/SQL execution in clustered nodes.

Incompatible OS patches or RAC library mismatches.

Memory corruption in SGA or PGA on a specific node.

Step 1: Identify the Node and Process

Check the alert logs for all nodes. Determine which node the error occurred on and the corresponding session or process.

Step 2: Examine Trace Files

Trace files provide stack details and help identify the offending SQL or PL/SQL operation. Locate them at:

$ORACLE_BASE/diag/rdbms/<db_name>/<SID>/trace

Step 3: Analyze RAC-Specific Issues

Look for issues in interconnect communication and cache fusion.

Check for known RAC bugs in Oracle Support using the first ORA-07445 argument.

Confirm OS patches and RAC library versions are consistent across nodes.

Step 4: Apply Fixes or Workarounds

Apply recommended patches for RAC or the Oracle version.

Adjust or optimize SQL causing repeated errors.

Reboot the affected node if memory corruption is suspected.

Engage Oracle Support for unknown or critical errors affecting multiple nodes.

Step 5: Monitor and Prevent Recurrence

Enable RAC diagnostics and health checks.

Monitor memory usage on each node.

Regularly check alert logs and apply cluster-wide patches.

Conclusion

ORA-07445 in RAC environments can disrupt clustered systems, but careful trace analysis, patching, and RAC-specific monitoring ensure high availability while resolving internal exceptions efficiently.