Hello @Brandon3,
Unfortunately, ndmpcopy doesn’t do deduplication or file-level checks.... it’s a straight copy operation. If the destination already has data, it won’t reconcile or skip duplicates, so you’ll want to plan around that.
A couple of clarifying questions that will help narrow down the best approach for you:
- What NetApp ONTAP platform are you running on (AFF, FAS, or ASA)?
- Which ONTAP software version are you currently using? Some features and behaviors differ between releases.
- What storage efficiency ratio are you seeing on the destination volume (deduplication, compression, compaction)?
- Is the destination volume already serving data to clients, or is it purely a replication target?
- Do you need this to be a one-time copy, or an ongoing sync/replication?
With those details, it’ll be easier to recommend whether ndmpcopy is the right tool, or if SnapMirror or XCP might be a better fit for your use case.
NDMP is a protocol designed for backups, and while you can still use it for copy operations you need to understand its limitations. For example, you could have a heap of deduplicated data on your source volume (even 2:1) that is going to your destination volume with either deduplication disabled or even post-process deduplication (e.g. FAS)......... it will fill up.
There is also a great KB article here which discusses the incremental copy feature of ndmpcopy What is the difference between levels 1 to 9 for an incremental copy - NetApp Knowledge Base which depending on your use case could help.