ferrus wrote:So I could turn on deduplication on the Tier1 DAS storage - without a negative effect on the Tier2 Datadomain copy?
Correct. Just don't forget to disable it in the backup copy.
ferrus wrote:Between Local 16TB+ and Local, which would you expect to be better in this environment?
I believe that the Backup and Backup Copy setting should match, so it should be one that works best for both?
Correct. Worth trying both to see which one works better on average. Or think of which backup storage is involved in restores more frequently or has lower RTO, since 'Local target' is good for your primary backup storage and 'Local 16TB+' for secondary.