Round-robin and/or Failover configurations in ArcGIS Server for the Java Platform do not work as expected at version 9.3.1 Service Pack 1

Last Published: April 25, 2020


**This issue has been resolved in ArcGIS 9.3.1 Service Pack 2.**

In ArcGIS Server, Failover and Round-robin are two methods for configuring multiple Server Object Manager (SOM) machines.

After applying Service Pack 1 to ArcGIS Server 9.3.1 for the Java Platform, unexpected behavior is experienced with Round-robin and/or Failover in the Server environments.

With Round-robin, the request is always sent to the secondary host.

With Failover, if a failure occurs with the primary host SOM machine, the initial failover from the primary to a secondary SOM host works as expected. However, if the primary host machine becomes available again, the requests continue to go to the secondary host. If the secondary host goes down, then the requests do not failover back to the primary host machine.


Service Pack 1 has introduced a bug into the Round-robin and Failover mechanism.

For reference the bug number and synopsis are NIM052853 - Round-robin or failover configuration do not work as expected.


Below are two options for working around this issue:

If the version 9.3.1 Service Pack 1 has already been installed and this issue is occurring, please contact ESRI Technical Support.

  1. Front ArcGIS Server instances with a Network Load Balancer.
  2. Do not apply version 9.3.1 Service Pack 1 at this time if Round-robin or Failover is being used with ArcGIS Server. Please wait until version 9.3.1 Service Pack 2, where this issue is addressed, is available.

Article ID:000010872

  • ArcGIS Server

Receive notifications and find solutions for new or common issues

Get summarized answers and video solutions from our new AI chatbot.

Download the Esri Support App

Related Information

Discover more on this topic

Get help from ArcGIS experts

Contact technical support

Download the Esri Support App

Go to download options