Load Generators Deployed in GCP Fail to Connect or Go Non-Operational in LRE via MI Listener

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Applies To:

1. LoadRunner Enterprise (LRE) 2022 R2 and later
2. LRE Patch 03 and Load Generator Patch 04
3. Environments using MI Listener for communication between cloud-based Load Generators (e.g., GCP, AWS) and on-premises LRE instance

Issue:

When attempting to connect Load Generators (LGs) deployed in Google Cloud Platform (GCP) to an on-premises LoadRunner Enterprise (LRE) instance through an MI Listener, the following issues may occur:

1. Only some of the Load Generators can be added successfully.
2. Successfully added Load Generators intermittently appear as Non-Operational.
3. Result collation fails after test execution.
4. Some LGs display the error 'Host configuration is not valid' during registration.

Cause:

These issues can occur due to one or more of the following reasons:

1. Network instability or latency between the GCP Load Generators and the MI Listener causing connection timeouts.
2. Insufficient connection timeout settings in the Agent configuration on the Load Generator.
3. Temporary unavailability or downtime of MI Listener services.
4. Mismatched patch levels between the LRE server and Load Generators.
5. Firewall or proxy rules intermittently blocking communication ports.
6. Agent service type configuration issues (Service vs. Process mode).

Steps:

Follow the steps below to verify and stabilize communication between the GCP-based Load Generators and the LRE instance:

1. Verify Environment Compatibility and Patches

Ensure the following combinations are supported and consistent across components:

• LRE 2022 R2 + Patch 03
• LRE Load Generator 2022 R2 + Patch 04

Mismatched versions can cause connection and operational issues.

2. Verify MI Listener Configuration

• Confirm that IIS or any other web server is not installed on the MI Listener, as it can occupy required ports (typically 443).
• Ensure the MI Listener service is running and healthy. If the service stops, connected Load Generators may go into a Non-Operational state.

3. Validate Network Connectivity

From each Load Generator VM, run the following command to verify connectivity:

• Test-NetConnection -ComputerName <MIListener_FQDN> -Port 443

Confirm that firewall rules allow outbound TCP 443 traffic from the GCP network to the MI Listener.

4. Adjust Agent Connection Timeout

• Launch the following tool on each Load Generator:
    <LRE root>\launch_service\bin\AgentConfig.exe
• Navigate to Settings → Enable Firewall Agent.
• Increase Connection Timeout to at least 60 seconds (120 seconds recommended for cloud environments).
• Apply and confirm all settings.

5. Test Agent Operation Mode

• Try running the agent both as a Service and as a Process to identify which mode provides more stable connectivity.
• Restart the Load Generator service after switching modes.

6. Recover Non-Operational Hosts

If Load Generators appear as Non-Operational in the LRE Administration interface:

• Verify MI Listener service status.
• Restart the MI Listener service if it has stopped.
• In LRE Administration → Load Generators, select the host and click Check Host.
• Wait for the status to update to Operational.

7. Validate Result Collation

If result collation fails after test execution:

• Confirm that MI Listener is reachable during collation.
• Check LRE logs under:
    %ProgramData%\Micro Focus\LoadRunner Enterprise\Logs

• Restart MI Listener and retry collation if communication was interrupted.

   

Additional Info:

1. Monitor MI Listener performance and resource usage, especially if multiple cloud Load Generators are connected simultaneously.
2. Consider increasing the connection timeout further for high-latency environments (up to 180 seconds).
3. Periodically restart the MI Listener to clear stale connections.

These issues typically occur due to communication latency or MI Listener service interruptions between cloud-based Load Generators and the on-premises LRE instance. Ensuring consistent patch versions, adjusting timeout settings, and maintaining stable MI Listener availability usually resolves the problem.

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