V11 SP8

OSDP C-Mode Optimized Block-Level Replication

By default, the OSDP C-Mode feature uses checksum block-level replication. However, you can enable optimized block-level replication, which is faster and more efficient than checksum block-level replication.

Replication methods replicate only blocks that changed after the most recent backup. To determine which blocks have changed, the checksum method reads the entire volume each time a backup job runs. This process can be time-consuming and resource-consuming.

The optimized block-level replication method does not read the entire volume. Instead, this method uses a block-level filter driver that monitors the volume and tracks which blocks change.

Replication Jobs That Always Use the Checksum Method

The following jobs always use the checksum method, even if optimized block-level replication is enabled. After these jobs run, subsequent jobs can use the optimized block-level replication method.

  • The first replication job after you select the Optimized for block level replication (Open Systems Data Protection C-Mode) check box at the client level.
  • The first replication job after you associate a subclient from one storage policy to another.
  • The first replication job after the driver updates are installed on the client computer.
  • The first replication job after a volume is resized (extended or shrunk).
  • Every full replication job for the file system agent.
  • On UNIX, the first replication job after a client computer is rebooted.
  • On Windows, the first replication job after a volume’s GUID changes.
  • On Windows cluster, the first replication job after a cluster failover that causes a shared volume’s GUID to change.