How To Fix ICM021 - Host Name Buffer Is Empty

SAP Error Message - Details

• Message type: E = Error

• Message class: ICM - Messages for ICM Monitor

• Message number: 021

• Message text: Host Name Buffer Is Empty

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

Unfortunately, there isn't any extra information in this error notice.

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Smart SAP Assistant

• What is the cause and solution for SAP error message ICM021 - Host Name Buffer Is Empty ?

  The SAP error message "ICM021 Host Name Buffer Is Empty" typically occurs in the Internet Communication Manager (ICM) when the system is unable to resolve a hostname or when the hostname buffer is not properly populated. This can happen due to various reasons, including configuration issues, network problems, or DNS resolution failures.
  Causes:
  
  Incorrect Hostname Configuration: The hostname specified in the SAP system configuration may be incorrect or not resolvable.
  DNS Issues: The Domain Name System (DNS) may not be able to resolve the hostname to an IP address.
  Network Connectivity Problems: There may be network issues preventing the SAP system from reaching the DNS server or the target host.
  ICM Configuration: The ICM may not be properly configured to handle the hostname or may have issues with its internal buffers.
  Missing or Incorrect Entries in the Hosts File: If the hostname is not correctly defined in the local hosts file, it may lead to this error.
  
  Solutions:
  
  
  Check Hostname Configuration:
  
  Verify that the hostname configured in the SAP system is correct. You can check this in transaction RZ10 or RZ11 for profile parameters related to the ICM.
  
  
  
  DNS Configuration:
  
  Ensure that the DNS server is correctly configured and reachable. You can test this by using command-line tools like nslookup or ping to see if the hostname resolves correctly.
  
  
  
  Network Connectivity:
  
  Check the network connectivity between the SAP system and the DNS server. Ensure that there are no firewall rules or network issues blocking access.
  
  
  
  Update Hosts File:
  
  If necessary, add the hostname and its corresponding IP address to the local hosts file (e.g., /etc/hosts on Unix/Linux or C:\Windows\System32\drivers\etc\hosts on Windows).
  
  
  
  ICM Configuration:
  
  Review the ICM configuration settings in the SAP system. Ensure that the parameters related to the hostname and buffer sizes are set correctly.
  
  
  
  Restart ICM:
  
  After making changes, restart the ICM to apply the new settings. This can be done through transaction SMICM.
  
  
  
  Check SAP Notes:
  
  Look for any relevant SAP Notes that may address this specific error. SAP frequently updates its knowledge base with solutions for known issues.
  
  
  
  Related Information:
  
  
  Transaction Codes: 
  
  RZ10 (Profile Parameters)
  RZ11 (Profile Parameter Maintenance)
  SMICM (ICM Monitor)
  
  
  
  Logs: 
  
  Check the ICM logs for more detailed error messages. You can find these logs in the SAP system under the dev_icm file.
  
  
  
  SAP Community: 
  
  Consider searching or posting in the SAP Community forums for additional insights or similar experiences from other users.
  
  
  
  By following these steps, you should be able to diagnose and resolve the "ICM021 Host Name Buffer Is Empty" error in your SAP system.