1. A method, comprising: configuring, by a source storage system, a logical volume to comprise source regions of the source storage system that have a mapping between a host computer and the source storage system, the source regions storing source data; copying the source data from the source regions to target data in target regions of a target storage system, the target regions being in a one-to-one correspondence with the source regions; reconfiguring the logical volume so that the target regions have the mapping between the host computer and the source storage system; receiving, by the source storage system, a request to store an update to the one of the source regions, storing the update to the one of the source regions, and storing the update to the corresponding target region; and copying attributes and run-time information for the logical volume from the source storage system to the target storage system, and deleting the source data.