How To Fix CSM_VMC025 - Number of VMs in "sticky" mode

SAP Error Message - Details

• Message type: E = Error

• Message class: CSM_VMC - Messages for VM Container Monitoring

• Message number: 025

• Message text: Number of VMs in "sticky" mode

What causes this issue?

"Sticky" mode means that a Java virtual machine has been permanently
assigned to a user context. If a VM has this operating mode, all
requests for the assigned user context can only be processed in this VM.
As a result, this VM, provided the associated Java session (and the user
context too) is not closed, is not available to other transactions and
users. (The ABAP analogon is the PRIV mode of work processes.)
A VM enters the "sticky" mode if within a client request the memory size
of the user context (Java session) exceeds the defined value
<DS:KENO.E43B6C44FA33B04DE10000000A42425B>Memory parameters</>).
You can control the behavior in the VMC system administration (SM53) by
setting the value in the view "Sitzungen".
You can find more information in the online documentation
<DS:KENO.001560AA0E081DEB91FD8250BEB8055A>VMC System Administration</>
(transaction SM53).

System Response

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

How to fix this error?

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CSM_VMC025 - Number of VMs in "sticky" mode ?

  The SAP error message CSM_VMC025 indicates that the number of virtual machines (VMs) in "sticky" mode has reached its limit. This typically occurs in environments where SAP systems are deployed on virtualized infrastructure, such as SAP HANA on VMware or other cloud platforms.
  Cause:
  The "sticky" mode refers to a configuration where certain VMs are bound to specific physical hosts or resources to ensure performance consistency and reduce latency. The error message CSM_VMC025 suggests that the maximum number of VMs that can be in this sticky mode has been exceeded. This can happen due to:
  
  Resource Limitations: The infrastructure may have a predefined limit on the number of VMs that can be in sticky mode.
  Configuration Issues: Incorrect settings in the virtualization management layer or SAP configuration.
  Increased Load: An unexpected increase in the number of VMs being deployed in sticky mode due to scaling or other operational changes.
  
  Solution:
  To resolve the CSM_VMC025 error, consider the following steps:
  
  Review Configuration: Check the configuration settings for the virtualization environment to ensure that the limits for sticky VMs are appropriate for your workload.
  Increase Limits: If possible, increase the limit for the number of VMs allowed in sticky mode. This may require changes in the virtualization management settings or consultation with your infrastructure team.
  Reconfigure VMs: If certain VMs do not require sticky mode, consider reconfiguring them to operate in a non-sticky mode to free up capacity.
  Monitor Resource Usage: Use monitoring tools to keep track of VM usage and performance to prevent hitting limits in the future.
  Consult Documentation: Refer to the SAP and virtualization platform documentation for specific guidelines on managing sticky VMs and understanding the limits imposed by your infrastructure.
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may provide additional insights or patches related to this error.
  Virtualization Documentation: Review the documentation for your specific virtualization platform (e.g., VMware, Hyper-V) for best practices on managing VM configurations and limits.
  SAP Community: Engage with the SAP Community forums to see if other users have encountered similar issues and what solutions they have implemented.
  
  By following these steps, you should be able to address the CSM_VMC025 error and optimize your SAP environment's performance.