ABS is the distributed block storage component of ACOS clusters. It provides storage services for replication objects. At the data layer, a replication object corresponds to one or more virtual volumes in ABS. Asynchronous replication of a protected object by the replication service is asynchronous replication of virtual machine data.
When the replication service asynchronously replicates a protected object, controller-manager on the target-side replication service creates a snapshot through AOC, and then uses the source-side replication service proxy to query ABS volume metadata and read protected object snapshot data. Finally, the data is written to ABS in the target cluster through the RPC protocol to complete data replication.
When failback is required for a protected object, controller-manager of the target-side replication service creates a replica object snapshot through AOC, and then reads the replica object snapshot data from ABS through the RPC protocol. Finally, the source-side replication service agent writes the data to ABS in the source cluster to complete data transmission back to the source.
