An ArcGIS Server site is composed of one or more GIS server machines that have the GIS Server component installed. Web service requests for maps, address coordinates, geoprocessing jobs, and so on, are each assigned to an available machine within the site. That machine then does the work of drawing the map, finding the address coordinate, running the geoprocessing tool, and so on, and returns the result to the client. Essentially, GIS server machines are the work centers of your site.
If you need to expand your site, you can add additional machines to your site using ArcGIS Server Manager or ArcGIS for Desktop.
Criteria for adding a GIS server to a site
Before you add a GIS server to a site, you should ensure that it meets the following criteria:
- It must be running on the same operating system platform as the other GIS server machines in the site. It is recommended that you use the same operating system version and hardware resources for all GIS servers in your site. For example, if you have a site comprised of GIS servers, each running on Windows Server 2008 R2 with a 3 GHz processor and 8 GB of RAM, the GIS server you add to the site should also have the same operating system and hardware specifications.
- It must be at the same version number as the other GIS server machines in the site.
- It must have the same license applied to it as the other GIS server machines in the site.
- It must be able to read and write to the site's configuration store and server directories. See About the configuration store and About server directories to learn about this requirement.
- It must be running ArcGIS Server under the same ArcGIS Server account as all the other GIS servers in the site. This can be a domain account, or it can be a local account with a name and password that are identical on all GIS servers. See The ArcGIS Server account to learn more about this account.
- It must be able to communicate with all the other GIS servers in the site through the ports listed in Ports used by ArcGIS Server. This may require adjustment of firewall settings.
- It must be able to read any data referenced by services on the site. A good way to verify this is to check whether the machine has permissions to all the data storage locations registered with the site. See About registering your data with ArcGIS Server to learn more about these registered locations.
How to add GIS servers to your site
You can add GIS servers to your site using Manager or ArcGIS for Desktop. Follow the steps in the related topics below.