A geodata service allows you to access a geodatabase through a local area network (LAN) or the Internet using ArcGIS Server. The service exposes the ability to perform geodatabase replication operations, make copies using data extraction, and execute queries in the geodatabase. A geodata service can be added for enterprise geodatabases and file geodatabases.
Geodata services are useful in situations where you need to access geodatabases in remote locations. For example, a company may want to set up enterprise geodatabases to manage data in its Los Angeles and New York offices. Once created, each office can publish its enterprise geodatabase on the Internet using a geodata service. The geodata services can then be used to create replicas for the enterprise geodatabases. With geodatabase replication, the geodata services can also be used to periodically synchronize the changes in each geodatabase over the Internet.
Before working with geodata services, you should have a basic understanding of how geodatabases, geodatabase replication, and data extraction work. The topic Understanding distributed data is a good starting point. Additionally, it's helpful to have some experience performing replication and data extraction in the ArcGIS Desktop environment before attempting these operations with ArcGIS Server.
Preparing the geodatabase in ArcGIS Desktop
The first step in publishing any GIS service is to create the GIS resource that it will reference. For geodata services, the resource is either an enterprise geodatabase or a file geodatabase. You can create either of these types of geodatabases using ArcCatalog. See An overview of geodatabase design for more information.
If you plan on using your geodata services for geodatabase replication, you must make sure that the data is configured properly and is from an enterprise geodatabase. See Preparing data for replication for additional information.
Publishing a geodata service
As of 10.5, you must license your ArcGIS Server as an ArcGIS GIS Server in order to publish geodata services.
You publish a geodatabase to ArcGIS Server by right-clicking it in ArcCatalog or the Catalog window in ArcGIS Desktop and choosing the option to share it as a geodata service. Once published, the geodata service can be used for synchronizing replicas or working with a geodatabase in a web app or web service.