6.0.3

Table Of Contents
Table 54. Certificate Modes for ESXi Hosts
Certificate Mode Description
VMware Certicate Authority (default) By default, the VMware Certicate Authority is used as the
CA for ESXi host certicates. VMCA is the root CA by
default, but it can be set up as the intermediary CA to
another CA. In this mode, users can manage certicates
from the vSphere Web Client. Also used if VMCA is a
subordinate certicate.
Custom Certicate Authority Some customers might prefer to manage their own external
certicate authority. In this mode, customers are
responsible for managing the certicates and cannot
manage them from the vSphere Web Client.
Thumbprint Mode vSphere 5.5 used thumbprint mode, and this mode is still
available as a fallback option for vSphere 6.0. Do not use
this mode unless you encounter problems with one of the
other two modes that you cannot resolve. Some vCenter 6.0
and later services might not work correctly in thumbprint
mode.
Using Custom ESXi Certificates
If your company policy requires that you use a dierent root CA than VMCA, you can switch the certicate
mode in your environment after careful planning. The recommended workow is as follows.
1 Obtain the certicates that you want to use.
2 Remove all hosts from vCenter Server.
3 Add the custom CA's root certicate to VECS.
4 Deploy the custom CA certicates to each host and restart services on that host.
5 Switch to Custom CA mode. See “Change the Certicate Mode,” on page 167.
6 Add the hosts to the vCenter Server system.
Switching from Custom CA Mode to VMCA Mode
If you are using custom CA mode and decide that using VMCA works beer in your environment, you can
perform the mode switch after careful planning. The recommended workow is as follows.
1 Remove all hosts from the vCenter Server system.
2 On the vCenter Server system, remove the third-party CA's root certicate from VECS.
3 Switch to VMCA mode. See “Change the Certicate Mode,” on page 167.
4 Add the hosts to the vCenter Server system.
N Any other workow for this mode switch might result in unpredictable behavior.
Retaining Thumbprint Mode Certificates During Upgrade
The switch from VMCA mode to thumbprint mode might be necessary if you encounter problems with the
VMCA certicates. In thumbprint mode, the vCenter Server system checks only whether a certicate exists
and is formaed correctly, and does not check whether the certicate is valid. See “Change the Certicate
Mode,” on page 167 for instructions.
vSphere Security
166 VMware, Inc.