By default, the Auto Deploy server provisions each host with certificates that are signed by VMCA. You can set up the Auto Deploy server to provision all hosts with custom certificates that are not signed by VMCA. In that scenario, the Auto Deploy server becomes a subordinate certificate authority of your third-party CA.


  • Request a certificate that meets your requirements from your CA.
    • Key size: 2048 bits or more (PEM encoded)
    • PEM format. VMware supports PKCS8 and PKCS1 (RSA keys). When keys are added to VECS, they are converted to PKCS8
    • x509 version 3
    • For root certificates, the CA extension must be set to true, and the cert sign must be in the list of requirements.
    • SubjectAltName must contain DNS Name=<machine_FQDN>
    • CRT format
    • Contains the following Key Usages: Digital Signature, Non Repudiation, Key Encipherment
    • Start time of one day before the current time
    • CN (and SubjectAltName) set to the host name (or IP address) that the ESXi host has in the vCenter Server inventory.
  • Name the certificate and key files rbd-ca.crt and rbd-ca.key.


  1. Back up the default ESXi certificates.
    The certificates are located at /etc/vmware-rbd/ssl/.
  2. From the vSphere Web Client, stop the Auto Deploy service.
    1. Select Administration, and click System Configuration under Deployment.
    2. Click Services.
    3. Right-click the service you want to stop and select Stop.
  3. On the system where the Auto Deploy service runs, replace rbd-ca.crt and rbd-ca.key in /etc/vmware-rbd/ssl/ with your custom certificate and key file.
  4. On the system where the Auto Deploy service runs, update the TRUSTED_ROOTS store in VECS to use your new certificates.
    vecs-cli entry delete --store TRUSTED_ROOTS --alias
    vecs-cli entry create --store TRUSTED_ROOTS --alias
    				rbd_cert --cert /etc/vmware-rbd/ssl/rbd-ca.crt
    C:\Program Files\VMware\vCenter Server\vmafdd\vecs-cli.exe
  5. Create a castore.pem file that contains what's in TRUSTED_ROOTS and place the file in the /etc/vmware-rbd/ssl/ directory.
    In custom mode, you are responsible for maintaining this file.
  6. Change the certificate mode for the vCenter Server system to custom.
  7. Restart the vCenter Server service and start the Auto Deploy service.


The next time you provision a host that is set up to use Auto Deploy, the Auto Deploy server generates a certificate using the root certificate that you just added to the TRUSTED_ROOTS store.