Determine what is actually growing
Start with current usable capacity, cleanable space, recent growth rate, and filesystem status. Distinguish logical backup growth from physical consumption and identify whether the change is gradual or sudden.
Look for workload and retention changes
Check whether new backup clients, longer retention, larger full backups, replication changes, or application behavior changed around the start of the growth. Capacity problems are often symptoms of upstream policy changes.
Understand cleaning before forcing actions
Data Domain space reclamation depends on its filesystem and cleaning behavior. Do not delete data or repeatedly force maintenance simply because a dashboard shows high utilization. First understand retention, expired data, cleanable space, and the expected effect of cleaning.
Protect replication and recovery requirements
Capacity remediation should not undermine recovery objectives. Before shortening retention or deleting backup sets, confirm business retention requirements, replicated copies, compliance constraints, and restore dependencies.
Plan before the filesystem becomes critical
High utilization leaves less operational margin. Build a trend from recent growth, estimate time to thresholds, and decide whether the right answer is policy correction, workload cleanup, additional capacity, or architecture changes.
This article is a general troubleshooting framework. Validate commands and procedures against your platform version, vendor documentation, support requirements, and change-control process before making production changes.