How To: Configure failover/round-robin with the Java Web ADF
Failover and round-robin are techniques used to provide a backup server in case one server in a configuration goes down. As a Web application is designed in Eclipse or Creator, additional GIS servers that the application use can be specified and whether they act in a failover or round-robin mode. Instructions provided describe how to configure failover/round-robin with the Java Web ADF.
There are two types of applications that can be set up to utilize ArcGIS Server in failover or round-robin scenario:
1. Web Application (must be an ArcGIS Server Local connection):
Edit the application's facesconfig.xml file to allow connection to multiple SOMs in a failover or round-robin fashion. This is done by adding more hosts to the managed-property 'hosts' and adding a new managed-property called 'clusterType'. For example, add the following to the facesconfig.xml file:
<!—- Edit the hosts managed-property values --> <managed-property> <property-name>hosts</property-name> <list-entries> <!—- Add values for your SOM servers --> <value>arcgis1.esri.com</value> <value>arcgis2.esri.com</value> </list-entries> </managed-property> <!—- Add a new clusterType managed-property --> <managed-property> <property-name>clusterType</property-name> <value>roundrobin</value> </managed-property>
2. Web Service Handler (WSH):
a) Using ArcGIS Server Manager, go to the ‘Services’ tab and select ‘Configure Services Handler’.
b) Select the ‘Export’ tab.
c) Under ‘Export Web Services’, select the type of service to export (REST or Web).
d) Fill in the appropriate GIS Server credentials to connect to.
e) Select the ‘Yes’ radio button under ‘Do you have additional GIS Servers in your site that you would like to use for a failover or round-robin configuration?’ and add the appropriate GIS Servers.
f) Once complete, export the application and deploy it to a supported application server.
Note: The username and password used must be able to connect to all the GIS Servers in the cluster for both application types.