Hello Dean
I will try to answer some of your questions:
1. What sort of replica do I need to create i.e. two way, one way, check out for the interstate users to be able to edit each day and then synchronise at night (or when they finish their edits).
It depends... If editions will be done in both central and replicated geodatabases, you will need a "two-way" replica. However, if editions will be done only by those editors against the replicated database.. I will recommend one-way, child to parent replica (replica is permanent, editions move from child to parent).
3. Do I need to create the replica on a regular basis or is it just a set and forget process?
With one-way or two-way replicas, it will be a "set and forget" process....
4. How do I automate the synchronisation process?
You can create a Python script and schedule it. The Python script can launch the "Synchronize..." tool in ArcToolBox.
5. Is there anything else that I need to know to ensure a simple implementation?
- it is not needed to create a replica with all the feature classes in the geodatabase; however, once you have created the replica there is no way for "editing" the replica including or removing new datasets; so be careful about which feature classes you include/exclude in the replica.... If you need to change these, you will need to "unregister" the replica and recreate again.
- use the ArcMap toolbar better than the ArcToolBox tools for replica creation . You can create an mxd with all the feature classes you are going to replicate; error messages are more descriptive using the ArcMap toolbar.
- if you create a python script for automate the sync. process. try to log the result.
Hope this helps
Jesús de Diego