Replication Task and Periodic Snapshot Task Confusion - Schedule


Aug 16, 2012
In "Replication Tasks" I choose a Periodic Snapshot Task. In its description it states:

Help: Periodic Snapshot Tasks

Snapshot schedule for this replication task. Choose from previously configured Periodic Snapshot Tasks. This replication task must have the same Recursive and Exclude Child Datasets values as the chosen periodic snapshot task. Selecting a periodic snapshot schedule removes the Schedule field.

What does this mean? The Schedule field for the Replication Task isn't "removed" when I choose the Periodic Snapshot Task, nor is the one in the Periodic Snapshot Task so not sure which schedule it's going to use. I am assuming it used the "Periodic Snapshot Task" schedule and if so then what happens in the cycle? Does the Periodic Snapshot Task trigger the replication task when it's completed?

***** UPDATE
I ran some tests and if you setup a Replication Task that uses an associated snapshot, the Periodic Snapshot Task schedule will be used, so when that time comes and snapshot is taken and then replicated
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Sep 18, 2020
I wound up not using replication for other technical reasons between my two Truenas systems, but from what I remember, the replication task requires a periodic snapshot task in order to replicate the data between the zfs file systems. If you already have a periodic snapshot task configured and in use on a schedule, you can use that as the scheduled periodic snapshot task the replication task requires and not have to create a new snapshot task for the replication task. Current snapshot tasks should show up in the dropdown for the replication task setup. This would be in place of the replication setup creating a new snapshot task and schedule to work with.