You can use volume SnapMirror to replicate a deduplicated volume to a secondary storage system (destination).
Deduplication can be enabled, run, and managed only from the primary storage system. However, the FlexVol volume at the secondary storage system inherits all the deduplication attributes and storage savings through SnapMirror.
The shared blocks are transferred only once, therefore deduplication also reduces the use of network bandwidth.
The volume SnapMirror update schedule is not tied to the deduplication schedule.
The maximum volume size limit is imposed based on the lower maximum volume size limit of the source and destination volumes. When creating a SnapMirror relationship between two different storage system models, ensure that the maximum volume size with deduplication is set to the lower maximum volume size limit of the two models.
Example
A FAS3020 system supports a maximum volume size with deduplication of 2 TB, whereas a FAS3050 system supports 3 TB, and volume SnapMirror relationship is established from FAS3020 to FAS3050. In this configuration, ensure that the volume SnapMirror relationship is established for 2 TB (FAS3020).
After a failover, if the volume size on the FAS3050 system is increased to more than 2 TB, you will not be able to perform a new baseline transfer or resync between the storage systems, because the FAS3020 system has a maximum volume size with deduplication of 2 TB.
Starting from Data ONTAP 7.3.1, if the volume size was ever increased beyond the deduplication supported limit and later it was shrunk within the supported limit, then such volumes can be part of SnapMirror primary storage system and secondary storage system.
When configuring volume SnapMirror and deduplication, you should consider the deduplication schedule and the volume SnapMirror schedule. As a best practice, start volume SnapMirror transfers of a deduplicated volume after deduplication has completed (that is, not in the middle of the deduplication operation). This step is performed to avoid sending undeduplicated data and additional temporary metadata files over the network. If the temporary metadata files in the source volume are locked in Snapshot copies, these files also consume extra space in the source and destination volumes.