An Incremental Replication of a SyncIQ policy only transfers the portions of files that have changed since the last run. Therefore, the amount of data replicated, and bandwidth consumption is significantly reduced in comparison to the initial replication.
Similar to the Initial Replication explained above, at the start of an incremental replication, the scheduler processes create the job directory. Next, the coordinator starts a process of collecting changes to the dataset, by taking a new snapshot and comparing it to the previous snapshot. The changes are compiled into an incremental file with a list of LINs that have been modified, added, or deleted.
After all the new modifications to the dataset are logged, workers read through the file and start to apply the changes to the target cluster. On the target cluster, the deleted LINs are removed first, followed by updating directories that have changed. Finally, the data and metadata are updated on the target cluster.
As all updates complete, the coordinator creates the job report, and the replication is complete.