Configuring DataDomain Integration for existing jobs after upgrade to v8

After upgrade to Veeam B&R v8 you can leverage integration with DataDomain over DD Boost. 

You need to create new type of repository and map existing backup chain over this new repository.

If DD Boost is already enabled on the storage unit you have been backing up to:

1. Create new repository (Deduplicating storage appliance type) selecting the same storage unit with "Import existing backups automatically" checkbox enabled;
2. Go to the job setting, select "Map backup" and select backup chain from new repository;
3. Go to backups and find your backup chain on the CIFS/NFS repository, right click on it and select "Remove from backups";

If DD Boost isn't enabled on the storage unit you have been backing up to:

1. Create new storage unit through DataDomain console (Disk management -> DD Boost -> Storage Units);
2. Create new repository (Deduplicating storage appliance type) selecting the brand new storage unit;
3. Make a clone of your existing job and select new repository in the job settings.
4. Remove old job;

Due to DataDomain architectural limitation you cannot enable DD Boost on existing storage unit that's why you need to create a new storage unit. There is no instruments to migrate files from one storage units to another.
Keep in mind that Veeam will initiate active full however all data will be deduplicated by DD Boost on the proxy and you won't notice high network saturation between Veeam backup proxy and DataDomain server.
Also you need to remove old backup chain manually once you decide you no longer need it. In order to remove it go to backups and find your backup chain on the CIFS/NFS repository, right click on it and select "Remove from backups"