A Log Catchup gap in Nutanix Database Service (NDB) occurs when transaction logs are missing or corrupted, disrupting point-in-time restore (PITR) operations for cloning or database restoration via Time Machine. The NDB Time Machine Heal Snapshot feature addresses this by repairing snapshots to resolve such gaps.

Option A (By default the time machine auto-heal feature is enabled) is incorrect because the auto-heal feature is not enabled by default; it requires explicit configuration or manual invocation.

Option B (Manual Heal is only used when gaps in Log Catchup are detected once the operation has begun failing) is incorrect because manual heal can be initiated proactively or reactively, not solely after failure detection.

Option C is correct because a successful Time Machine Heal process restores the snapshot integrity, allowing PITR to span the previously gapped period.

Option D is correct as the auto-heal process, when enabled, runs every 5 minutes to detect and address healable conditions, aligning with NDB’s automated maintenance schedule.

Together, C and D reflect the operational mechanics of the Heal Snapshot feature.

References

Nutanix Database Service (NDB) User Guide, Chapter 5: Configuring Time Machines, Section: Healing Snapshot Gaps

Nutanix Support & Insights, Knowledge Base Article: "Resolving Log Catchup Gaps with Time Machine Heal"

Nutanix Certified Professional - Database Automation (NCP-DB) v6.5 Blueprint, Section 5: Protect Databases Using Time Machine