What is a geodata service?
A geodata service allows you to access a geodatabase through a local area network (LAN) or the Internet using ArcGIS for 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 ArcSDE 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 ArcSDE geodatabases to manage data in its Los Angeles and New York offices. Once created, each office can publish its ArcSDE geodatabase on the Internet using a geodata service. The geodata services can then be used to create replicas for the ArcSDE 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 for Desktop environment before attempting these operations with ArcGIS for Server.
Preparing the geodatabase in ArcGIS for 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 ArcSDE geodatabase or a file geodatabase. You can create any 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 ArcSDE geodatabase. See Preparing data for replication for additional information.
Publishing a geodata service
You publish a geodatabase to ArcGIS for Server by right-clicking it in ArcCatalog or the Catalog window in ArcGIS for 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 application or web service.