For guest level backups, the data will be de-duplicated.
For image level backups, Avamar uses Data Domains fixed segmentation size mode for performance reasons. If the data is allocated to the disk along the same block boundaries, the data will have excellent (though not perfect) de-duplication. However, if the data is written to the new VM at an offset compared with the copy on the other VM, the deduplication will be poor because the shift in alignment makes all the blocks on the new VM look like new data to the de-duplication algorithm.
Please do note that DDBoost will sometimes send duplicate segments on purpose to ensure that data is stored contiguously on disk on the appliance. This is for performance reasons. These duplicate segments are cleaned up automatically during the weekly cleaning cycle.
If the data was de-duplicated, deleting serverA will not recover very much (if any) space. If you review the Avamar DPN Summary report for the time period when the data was copied to server2, you should be able to see whether there was a large jump in the bytes sent value. If there was a large jump, deleting serverA may recover some space. If there wasn't a significant ingest of new bytes, you'd be better off keeping the backups for serverA around since they're not costing you much additional capacity.
ionthegeek
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June 11th, 2021 07:00
For guest level backups, the data will be de-duplicated.
For image level backups, Avamar uses Data Domains fixed segmentation size mode for performance reasons. If the data is allocated to the disk along the same block boundaries, the data will have excellent (though not perfect) de-duplication. However, if the data is written to the new VM at an offset compared with the copy on the other VM, the deduplication will be poor because the shift in alignment makes all the blocks on the new VM look like new data to the de-duplication algorithm.
Please do note that DDBoost will sometimes send duplicate segments on purpose to ensure that data is stored contiguously on disk on the appliance. This is for performance reasons. These duplicate segments are cleaned up automatically during the weekly cleaning cycle.
If the data was de-duplicated, deleting serverA will not recover very much (if any) space. If you review the Avamar DPN Summary report for the time period when the data was copied to server2, you should be able to see whether there was a large jump in the bytes sent value. If there was a large jump, deleting serverA may recover some space. If there wasn't a significant ingest of new bytes, you'd be better off keeping the backups for serverA around since they're not costing you much additional capacity.