Database Management

DPA monitor fails to start on SQL AG listener with max allowed monitored database sessions exceeded

This involved SolarWinds DPA monitors failing to start for a SQL Server Availability Group listener because the monitored database session threshold was being exceeded. The reported error indicated max allowed monitored database sessions exceeded: 23 > 20 and referenced checking whether the instance was registered through multiple AG listeners.

First published date

6/24/2026 4:09 PM

Last published date

6/24/2026 4:09 PM

Overview

The issue was traced to DPA monitored-session limit settings in system.properties. Troubleshooting focused on confirming the correct file location, increasing the relevant session-limit values, and restarting the Ignite / DPA service. 

Product section

Database Performance Analyzer

Cause

The failure was tied to DPA monitored database session limits rather than a generic monitor startup issue.

Resolution

  • Confirm the correct system.properties file location on the DPA server.

  • Review the monitored session limit settings and make sure they are active (not commented out).

  • Recommended values used during troubleshooting:

    • com.confio.idc.database.datasource.maxAllowedSessions=25

    • com.confio.idc.database.datasource.maxAllowedSessionsForAg=30

  • Restart the Ignite / DPA service after updating the values.