A replication log is the record of data being replicated to the object store. Each protected domain uses a single replication log for all the VMs belonging to the protected domain.
The shared non-volatile memory resource in the protected site that is dedicated for the use of JetStream DR software. Exposed to the DRVA(s) as an iSCSI LUN, or VMDK-based virtual disk, the replication log volume is used to maintain replication logs as well as garbage collection metadata and other metadata created by the JetStream DR software.