ArcGIS Server Cloud Builder on Amazon Web Services (AWS) gives you various options for your ArcGIS Server site architecture. For example, you can choose to put multiple GIS server instances in your site to handle large processing loads, and you can choose to put the geodatabase on its own instance to isolate it from the GIS server tier. This topic discusses the architecture options available when building your site with Cloud Builder. It also explains architecture guidelines and limitations if you're building an ArcGIS for Server site manually using the AWS Management Console.
Architectures available with Cloud Builder
ArcGIS Server Cloud Builder on Amazon Web Services allows you to build a simple site with one GIS server to a complex site with many GIS servers. It also allows you to include an enterprise geodatabase and determine where the enterprise geodatabase is placed.
A GIS server without an enterprise geodatabase
You can use Cloud Builder to create an ArcGIS Server site running on Windows or Linux without an enterprise geodatabase. Such a site can have one or many GIS servers. All the participating GIS servers must use the same operating system. In all cases, the GIS server or servers are placed beneath an Amazon load balancer.
A GIS server with an enterprise geodatabase on the same EC2 instance
You can optionally choose to create a site that has an enterprise geodatabase running on the same EC2 instance as ArcGIS Server. If the site contains multiple GIS servers, the enterprise geodatabase runs on just one of those servers.
If you built your ArcGIS Server site on Linux, the enterprise geodatabase runs on PostgreSQL. If you build your ArcGIS Server site on Windows, the enterprise geodatabase can run on Microsoft SQL Server Express or SQL Server Standard.
Running the enterprise geodatabase on the same EC2 instance as ArcGIS Server can help you save hardware costs (the hourly fees you pay to Amazon for use of the instances). This architecture also reduces latency between the server and the database. However, when you run the server and the database on the same EC2 instance, you are sharing hardware resources and run a greater risk of site disruption if either component is overloaded or goes offline.
A GIS server with an enterprise geodatabase on its own EC2 instance
You can choose to create a site that has an enterprise geodatabase running on its own EC2 instance, separate from the ArcGIS Server EC2 instances. If you built your ArcGIS Server site on Linux, the enterprise geodatabase runs on PostgreSQL. If you built your site on Windows, the enterprise geodatabase runs on SQL Server Standard. If you choose to create a site with an Amazon Relational Database Service (RDS) for Microsoft SQL Server, it will always run on an instance separate from your ArcGIS Server instances.
Running the enterprise geodatabase on a separate instance from ArcGIS Server can result in increased fees for instance usage. However, separating the GIS server and database tiers gives you more freedom to adjust or fix one tier without affecting the other.
Architectures available when building your site manually
When you build your site manually using the AWS Management Console, you can launch one or many EC2 instances running ArcGIS for Server. If you launch multiple instances, you must also launch an Amazon load balancer and add the instances to it. All GIS server instances you add beneath the load balancer must be identical.
Each GIS server instance beneath the load balancer operates independently of the other instances. In other words, each instance has its own configuration store, server directories, logs, and so forth. This limits the types of things you can do with the server, such as asynchronous geoprocessing or distributed map caching jobs. If you want a genuine distributed architecture that can do those things, use Cloud Builder to create your site.
When you build your site manually using the AWS Management Console, you can also launch one EC2 instance running ArcGIS for Server, Portal for ArcGIS, and ArcGIS Data Store.
There are three Esri Amazon Machine Images (AMIs) you can choose when launching instances for your site, or you can use a custom AMI that you have derived from one of these three AMIs. All the AMIs include ArcGIS for Server, Portal for ArcGIS, ArcGIS Data Store, and a database management system in which you can create geodatabases. When you build a site using the AWS Management Console, you must use a geoprocessing tool or Python to create the geodatabases.
Do I need to install the ArcGIS Web Adaptor?