Live Sync I/O attaches Commvault plug-ins to each source VM, leveraging vSphere APIs for I/O Filtering (VAIO filters) to capture block-level I/O for each VM disk.

The Commvault plug-ins for each VM pass transaction records through daemons at the source ESX cluster (CVBLRH) to the Block-Level Replication (BLR) service. The BLR service at the source sends the collected data from the source ESX cluster to the BLR service at the destination cluster, updating the Recovery Point Store (RP Store) and passing updates through CVBLRT daemons to each destination VM.

The RP Store at the destination maintains recovery point data and metadata for each VM.

Commvault Filter Components

BLR Architecture - sites