ArcGIS Server is designed to be scalable; it can accommodate both small and large deployments. When you first begin building your site, you might want to start small and install all the components on a single machine. As you deploy your production site, or if your site needs to handle more users, you can add more GIS servers. You can also integrate your site into your existing IT infrastructure by using your own enterprise web server (for example, via ArcGIS Web Adaptor), database, or enterprise identity providers. ArcGIS Server can also be configured to support critical business operations through the use of high availability configurations.
This help book describes different ways you can architect your ArcGIS Server site to meet different capacity and availability requirements. The following terms are used when explaining each deployment scenario:
- Site—An ArcGIS Server site consists of several components, such as a GIS server and ArcGIS Web Adaptor. These components can optionally be distributed across multiple machines to increase computing power and redundancy. For a more detailed description, see Inside an ArcGIS Server site.
- GIS server—The main component of the site that does the work to satisfy requests issued to the GIS web services. A GIS server can generate maps, run tools, serve imagery, and perform many other operations offered by ArcGIS.
- Reverse proxy server—An optional third party component in your organization that is placed between a client and a server in a network infrastructure. Incoming requests are handled by the proxy, which interacts on behalf of the client with the desired server or service residing on the server. Most organizations set up a proxy server so that the site is not exposed directly to clients. For more information, see Using a reverse proxy server with ArcGIS Server.
- ArcGIS Web Adaptor—An optional component included with ArcGIS Server that allows you to configure a web entry point into your site. It integrates with your web server and distributes incoming requests among GIS servers. For more information, see About the ArcGIS Web Adaptor.
- Network load balancer (NLB)—A third party component that uses a distribution algorithm to load balance network traffic across a number of hosts, helping to enhance the scalability and availability of web services. It also typically provides high availability by detecting machine failures and automatically redistributing traffic to available machines.
- Server directories—A set of ArcGIS Server directories containing certain types of files that support your services. These files include map caches, search indexes, and geoprocessing job results. For more information, see About server directories.
- Configuration store—A file directory that contains configuration information about the site such as the list of GIS servers participating in the site. The configuration store must be available for your site to function. For more information, see About the configuration store.
- Data—Data supporting your web services, such as feature classes, tools, imagery, and locators. For more information, see Making your data accessible to ArcGIS Server.
The scenarios outlined in the following topics are presented as deployment guidelines for you to consider as you build your ArcGIS Server site. Although you could configure your site exactly as presented in one of the scenarios, these configurations are flexible and can be adjusted to fit specialized needs and hardware resources.