ArcGIS Data Store Startup Failure – "Connection to localhost:9876 refused" and "No valid connection to configuration store established"

Error Message

When attempting to start ArcGIS Data Store, users may encounter the following error messages:

• Error encountered: No valid connection to configuration store established.
• Extended error message: Connection to localhost:9876 refused. Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections.

This issue prevents the ArcGIS Data Store service from starting properly, potentially impacting related services and the overall ArcGIS Enterprise environment.

Cause

The primary cause of this error is that ArcGIS Data Store cannot connect to its internal PostgreSQL database, due to one or more of the following reasons:

• The service account running ArcGIS Data Store lacks sufficient file system permissions to access or manage the PostgreSQL postmaster.pid file.
• A stale or orphaned postmaster.pid file is left in the PostgreSQL data directory after an improper shutdown or crash.
• PostgreSQL is not listening on the expected port (9876), or the network/firewall configurations are blocking access.
• File system permissions are misconfigured, preventing proper initialization of the PostgreSQL service embedded within ArcGIS Data Store.

Solution or Workaround

Verify and Correct Directory Permissions

Ensure that the ArcGIS Data Store service account has full access (read, write, execute) to the PostgreSQL data directories

  cd /home/arcgis/arcgis/datastore/
  chmod -R 700 pgdata
  chmod -R 700 pgsql10.10

Avoid using chmod -R 777, which is overly permissive and does not guarantee service functionality or security.

Flush Firewall Rules (If Necessary)

If the error mentions connection refusal on port 9876, ensure that firewall rules are not blocking required ports:

iptables --flush

Then verify that PostgreSQL is listening:

netstat -aon | grep 9876

Check for Zombie PostgreSQL Processes

Make sure no leftover PostgreSQL processes are interfering:

ps -ef | grep postmaster

Terminate any orphaned processes before restarting the service.