RBS allows you to backup and restore between a Luna Remote Backup HSM and a hosted primary Luna HSM, where the two are distant from each other, while separating the backup responsibility from HSM partition ownership. That is, the person responsible for administering the Backup workstation (with attached Luna Remote Backup HSM) does not have Owner/User authentication (black PED Key) for the primary HSM's partition.
RBS is not a standalone feature. It is a service that facilitates certain scenarios when backing-up HSM partitions or restoring onto those partitions, using a backup HSM that is distant from the primary HSM and its host or client.
RBS is run on the computer that hosts the Luna Remote Backup HSM, only. Running RBS also requires running pedClient on that computer, as well as on the distant primary - the paired instances of pedClient form the communications link that makes RBS possible.
Examples of the primary HSM might be:
See "Prepare RBS to Support Backup / Restore".