ArcGIS Server is designed to be scalable and to accommodate both small and large deployments. When you first begin building your site, you may 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 ArcGIS Server machines to the site. You can also integrate your site into your existing IT infrastructure by using your own enterprise web server (as with ArcGIS Web Adaptor), database, or organization-specific identity providers. ArcGIS Server can also be configured to support critical business operations through the use of high availability configurations. You can also create multiple ArcGIS Server sites in your ArcGIS Enterprise deployment, with each site serving a different purpose or simply hosting more services.
This section of the ArcGIS Server help describes the different configurations system architects can use to accomplish their organizations' unique needs and goals. These topics provide details on the ArcGIS Server site components of ArcGIS Enterprise, whether the site is federated with a portal or stands alone. The following terms are used when explaining each deployment scenario:
- Site—An ArcGIS Server site consists of one or more ArcGIS Server machines and ArcGIS Web Adaptor. These components can optionally be distributed across multiple machines to increase computing power and redundancy. Each machine in a server site participates on equal terms. For a more detailed description, see Inside an ArcGIS Server site.
- ArcGIS Server—The main component of the site that processes requests issued to its GIS web services. ArcGIS Server can generate maps, run tools, serve imagery, and perform many other operations.
- ArcGIS Web Adaptor—A software component that allows you to configure a web entry point into your site. It integrates with your web server and distributes incoming requests among ArcGIS Server machines. It's recommended you use ArcGIS Web Adaptor with your server site, unless you are deploying third-party load balancing components and can ensure they will handle each of the Web Adaptor's responsibilities. For more information, see About the ArcGIS Web Adaptor.
- 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 Use a reverse proxy server with ArcGIS Server.
- Network load balancer (NLB)—An optional 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 server directories.
- Configuration store—A file directory that contains configuration information about the site, such as the list of ArcGIS Server machines participating in the site. The configuration store must be available for your site to function. You are able to specify the configuration store location.
- Data—Data supporting your web services, such as feature classes, tools, imagery, and locators. For more information, see Make 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.