Backing out of Deduplication

[soreilly2010]

Hi We are going to be starting to use Deduplication on our TSM 6.2 windows server 24TB Sequential Disk stgpool

The question I was asked and I can't find the answer - what happens if we need to back out and turn dedup off. What happens to the data that was already processed?

Anyone done this before / know how TSM handles this?

[soreilly2010]

If you turn data deduplication off for a storage pool by updating the storage pool definition, new data that enters the storage pool is not deduplicated.
Deduplicated data, which was in the storage pool before you turned off data deduplication, is not reassembled. Deduplicated data continues to be removed due to normal reclamation and deletion. All information about data deduplication for the storage pool is retained.
To turn off data deduplication for a storage pool, use the UPDATE STGPOOL command and specify DEDUPLICATE=NO.
If you turn data deduplication on for the same storage pool, duplicate-identification processes resume, skipping any files that have already been processed. You can change the number of duplicate-identification processes. When calculating the number of duplicate-identification processes to specify, consider the workload on the server and the amount of data requiring data deduplication.