Abstract: Described are techniques used in performing data replication processing. Data is replicated on a recovery site from a production site. When a disaster occurs, the state of the replication processing is determined and a restart copy of the data is made available from the recover site. Processing continues based on whether protection mode is desired such that the system executes using the recovery site as the restart with a replicated copy of the data. Data is propagated from the recovery site to the production site to resume operations and replication processing originating from the production site.

Abstract: Method and apparatus are disclosed for maintaining a logical volume identifier database, to track logical volume identifiers associated with logical volumes stored among a plurality of storage elements in a computer storage system. The database may include descriptive information for respective logical volumes, such as users authorized to access the logical volume or the user which created the logical volume.