How To Fix CLB453 - HTTP client: listen failed with exception &1

SAP Error Message - Details

• Message type: E = Error

• Message class: CLB - SAIL: Common messages

• Message number: 453

• Message text: HTTP client: listen failed with exception &1

What causes this issue?

The method LISTEN has been called at the HTTP client and it returned the
exception &syst-msgv1&.

System Response

The method in process will be cancelled.

How to fix this error?

If this is the first time you receive this error, try again later. The
reason might be that the server is offline for a short time.
If the error continues, ask your system administrator to check the
system availability.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CLB453 - HTTP client: listen failed with exception &1 ?

  The SAP error message CLB453 with the description "HTTP client: listen failed with exception &1" typically indicates an issue with the HTTP client configuration or network settings in the SAP system. This error can occur in various scenarios, such as when the system is trying to establish a connection to an HTTP server or when it is attempting to listen for incoming HTTP requests.
  Causes:
  
  Port Conflicts: The specified port for the HTTP client may already be in use by another application or service.
  Network Configuration Issues: There may be firewall rules or network settings that prevent the SAP system from establishing a connection.
  Insufficient Permissions: The user or service account running the SAP application may not have the necessary permissions to bind to the specified port.
  Incorrect Configuration: The HTTP client configuration in the SAP system may be incorrect, such as an invalid hostname or port number.
  Resource Limitations: The system may be running out of resources (e.g., file descriptors, memory) that are required to create new connections.
  
  Solutions:
  
  Check Port Availability: Ensure that the port specified for the HTTP client is not being used by another application. You can use tools like netstat to check for port usage.
  Review Network Settings: Verify that there are no firewall rules or network policies blocking the connection. Ensure that the SAP system can reach the target server.
  Adjust Permissions: Make sure that the user or service account running the SAP application has the necessary permissions to bind to the specified port.
  Validate Configuration: Double-check the HTTP client configuration in the SAP system. Ensure that the hostname, port, and other settings are correct.
  Monitor System Resources: Check the system resources to ensure that there are enough available resources for the HTTP client to function properly. If necessary, increase the limits on file descriptors or memory.
  Restart Services: Sometimes, simply restarting the SAP application or the underlying services can resolve transient issues.
  
  Related Information:
  
  SAP Notes: Check SAP Notes for any known issues or patches related to this error message. SAP frequently updates its knowledge base with solutions for common problems.
  Logs: Review the application logs (e.g., dev_http, dev_w0) for more detailed error messages that can provide additional context about the issue.
  SAP Community: Engage with the SAP Community forums to see if other users have encountered similar issues and what solutions they found effective.
  
  If the problem persists after trying the above solutions, consider reaching out to SAP support for further assistance.