When an aggregate with compressed data is copied by using the aggr copy command, the copy of the data at the destination storage system inherits all the compression attributes and storage savings of the original data.
Data ONTAP 8.1 can read volumes that contain data compressed by Data ONTAP 8.0.1, but Data ONTAP 8.0.1 cannot read volumes that contain data compressed by Data ONTAP 8.1. If the source storage system is running Data ONTAP 8.1 and the destination storage system is running an earlier version of Data ONTAP, the following operations take place at the destination storage system after the aggregate copy operation is complete and the aggregate is online:
Attempts to bring these volumes online fail.
For more information about aggregate copy, see the Data ONTAP Data Protection Online Backup and Recovery Guide for 7-Mode.