6.7

Table Of Contents
After each reboot, an ESXi host must be able to reach vCenter Server. vCenter Server requests the
key with the corresponding ID from the KMS and makes it available to ESXi.
If, after restoring connection to the KMS cluster, the virtual machine remains locked, see Unlock
Locked Virtual Machines.
2 If the connection is restored, register the virtual machine. If an error results when you attempt to
register the virtual machine, verify that you have the Cryptographic operations.RegisterVM
privilege for the vCenter Server system.
This privilege is not required for powering on an encrypted virtual machine if the key is available. This
privilege is required for registering the virtual machine if the key has to be retrieved.
3 If the key is no longer available on the KMS, a virtual machine alarm is generated and the following
message appears in the event log:
Virtual machine is locked because keys are missing on KMS cluster.
Ask the KMS administrator to restore the key. You might encounter an inactive key if you are
powering on a virtual machine that had been removed from the inventory and that had not been
registered for a long time. It also happens if you reboot the ESXi host, and the KMS is not available.
a Retrieve the key ID by using the Managed Object Browser (MOB) or the vSphere API.
Retrieve the keyId from VirtualMachine.config.keyId.keyId.
b Ask the KMS administrator to reactivate the key that is associated with that key ID.
c After restoring the key, see Unlock Locked Virtual Machines.
If the key can be restored on the KMS, vCenter Server retrieves it and pushes it to the ESXi host the
next time it is needed.
4 If the KMS is accessible and the ESXi host is powered on, but the vCenter Server system is
unavailable, follow these steps to unlock virtual machines.
a Restore the vCenter Server system, or set up a different vCenter Server system, then establish
trust with the KMS.
You must use the same KMS cluster name, but the KMS IP address can be different.
b Reregister all virtual machines that are locked.
The new vCenter Server instance retrieves the keys from the KMS and the virtual machines are
unlocked.
5 If the keys are missing only on the ESXi host, a virtual machine alarm is generated and the following
message appears in the event log:
Virtual machine is locked because keys are missing on host.
The vCenter Server system can retrieve the missing keys from the KMS cluster. No manual recovery
of keys is required. See Unlock Locked Virtual Machines.
vSphere Security
VMware, Inc. 171