PowerScale OneFS 9.8.0.0 Backup and Recovery Guide

Full and differential replication

If a replication policy encounters an issue that cannot be fixed (for example, if the association was broken on the target cluster), you might need to reset the replication policy. If you reset a replication policy, SyncIQ performs either a full replication or a differential replication the next time the policy is run. You can specify the type of replication that SyncIQ performs.

During a full replication, SyncIQ transfers all data from the source cluster regardless of what data exists on the target cluster. A full replication consumes large amounts of network bandwidth and can take a long time to complete. However, a full replication is less strenuous on CPU usage than a differential replication.

A differential replication determines if files exist on the target. If the files do exist, the job compares the data in those files between source and target checking for differences. If a difference is found, the entire file is transferred from the source to the target. Any new files will also be fully transferred.A differential replication consumes less network bandwidth than a full replication; however, differential replications consume more CPU. Differential replication can be faster than a full replication if there is an adequate amount of available CPU for the replication job to consume.