Unable to Assign TPM Module to VM Due to KMS Key Generation Error

Products

• VMware vCenter Server

Issue/Introduction

When attempting to assign a Trusted Platform Module (TPM) to a new or existing virtual machine (VM) in vCenter Server, the operation fails with a key generation error related to the Key Management Server (KMS).

Environment

- VMware vCenter Server 7.0 or later
- Third-party Key Management Server (KMS) configured as a key provider
- Attempting to create or modify VMs with TPM modules

Cause

This issue typically occurs when the KMS is unable to generate new keys. Common reasons include:

1. Exhausted key batch count in the KMS
2. Connectivity issues between vCenter Server and the KMS
3. Misconfiguration of the KMS or its integration with vCenter Server

Resolution

Follow these steps to troubleshoot and resolve the issue:

1. Check the KMS key batch count:
   a. Log in to your KMS management interface
   b. Locate the section for key batch or key pool management
   c. Verify the available key count
   d. If low or depleted, replenish the key batch according to your KMS vendor's instructions

2. Verify connectivity between vCenter Server and KMS:
   a. From the vCenter Server, ping the KMS server to ensure network connectivity
   b. Check firewall rules to ensure required ports are open between vCenter Server and KMS
   c. Verify SSL/TLS certificate validity if secure communication is used

3. Review KMS configuration in vCenter Server:
   a. Log in to the vCenter Server using the vSphere Client
   b. Navigate to Configure > Security > Key Providers
   c. Select your KMS provider and click "Edit"
   d. Verify all settings, including server address, port, and credentials
   e. Test the connection using the "Test Connection" button

4. Check vCenter Server logs for additional information:
   a. Access the vCenter Server via SSH or direct console
   b. Review the following log files for relevant error messages:
      - /var/log/vmware/vpxd/vpxd.log
      - /var/log/vmware/vpxd/vpxd-profiler.log

5. Consult KMS vendor documentation:
   a. Review your KMS vendor's documentation for specific troubleshooting steps
   b. Look for known issues or limitations related to key generation or VMware integration

6. If the issue persists, contact your KMS vendor's support for further assistance

After performing these steps, attempt to assign the TPM module to a VM again. If successful, the error should no longer occur.

Additional Information

• Connect a vCenter Server System to a Key Management Server (KMS) / Key Provider