How the Application Server Communicates with the Database Server

There are two types of server devices supported for use in the Aptify environment:

• Aptify Database Server: A computer that is running Microsoft SQL server and runs all of Aptify's server components. It stores the Aptify databases.
• Aptify Application Servers: These are optional servers that can download and execute Process Flow Runs from the Aptify Database Server. An Application Server has the Aptify Desktop client application and the Application Server component installed. One or more Application Servers on the network can run Scheduled Tasks and reduce the workload of client computers.

The following is an overview of how an Application Server communicates with an Aptify Database Server:

1. A system administrator installs and configures the Application Server component on a network computer.
   • The installation process adds the Aptify Asynchronous Processor to the computer's Windows Services.
   • Do not install the Application Server component on the computer that is running the Aptify Database Server.
   • In general, Aptify does not recommend installing the Application Server component on the computer that is running the Aptify database server in a production environment. However, you can install the Application Server on the database server in a test environment if you want to use this functionality but do not have another computer available for testing.
   • The organization's Aptify Database Server must already be installed and running before you add Application Servers to the system.
   • See Installing an Application Server for installation details.
      
2. Once installed, the Application Server polls the database server at regular intervals.
   • The Application Server is looking for Process Flow Run records with a Status of Pending.
   • Asynchronous Process Flows triggered by an Event Handler or a Scheduled Task create pending Process Flow Run records.
   • See How to Create a Process Pipeline for general information on creating Process Flows and configuring Event Handlers.
   • See Creating a Scheduled Task for information on creating Scheduled Task records.
   • The Polling Interval parameter determines how often the Application Server polls the database server. See About the Application Server Polling Interval for details.
      
3. The Application Server locates pending Process Flow Runs and downloads them from the database server.
   • When the Application Server downloads a Process Flow Run, the run record is automatically updated: the Status field changes to In-Progress, the Task Sent To Server check box is selected, and the Application Server's name appears in the Client Machine Name field.
   • An Application Server configured to process only targeted Process Flow Runs will only download runs where its name is specified in the Application Server field. The Application Server will not execute untargeted runs (that is, Process Flow Run records that have the Application Server field blank).
   • The Maximum Threads parameter determines the maximum number of Process Flow Runs the Application Server can execute concurrently. See About the Maximum Worker Threads Setting for details.
      
4. The Application Server executes the Process Flow specified by the Process Flow Run.
5. The Application Server updates the Process Flow Run record with the process results.
   • The record's Status field changes to Complete (if the run was executed without error) or Error (if an error occurred during execution).
   • The Application Server populates the Process Flow Result Code field with the appropriate result if the Process Flow Run completed without error. The available Result Codes depend upon the configuration of the Process Flow.
   • If the Result Code corresponds to a successful result, the Success check box is selected. Users designate specific Result Codes as successful during Process Flow configuration.
      
6. The Application Server continues to poll the database server at regular intervals, as specified by the Polling Interval parameter