Cluster verification failures due to hostname resolution issues

Description: The cluster verification utility (CVU) reports failures in several prerequisite checks due to inconsistent hostname resolution across cluster nodes when both IPv4 and IPv6 are enabled.

List of Failed Tasks:

• ASM Integrity: Checks the integrity of Oracle Automatic Storage Management (ASM) across the cluster nodes.
  • Severity: Critical
  • Status: Verification failed
• Node Connectivity: Tests connectivity between all cluster nodes.
  • Subnets tested: IPv4 subnet1, IPv4 subnet2
  • Severity: Critical
  • Status: Verification failed
• Hosts File: Checks the consistency of the hosts file across cluster nodes.
  • Severity: Critical
  • Status: Verification failed

Error:

PRVG-13632 : Host "<host-name>" resolves to IP address "<IPv4 address>" on the majority of cluster nodes but to address "<IPv6 address>" on nodes "<host-name>".

PRVG-13632 : Host "<host-name>" resolves to IP address "<IPv6 address>" on the majority of cluster nodes but to address "<IPv4 address>" on nodes "<host-name>".

Cause: With dual IP stack enabled, hostnames resolve to both IPv4 and IPv6 addresses, which are not consistent across all cluster nodes. This inconsistency causes the CVU checks to fail.

Solution: This is a known issue (Bug 37015893). The fix is included in the 19.26.0.0.250121 (January 2025) Oracle Clusterware (OCW) Release Update (RU) and applies to both Grid Infrastructure (GI) and RDBMS homes.

Workaround:

• Recommended: Upgrade the database to version 19.26 or later to include the fix, and then retry the operation.
• Alternative (not recommended): Disable the dual stack on the admin network of the compute nodes and retry the operation.