Specifications

If you upgrade vCenter Single Sign-On and vCenter Server, vCenter Single Sign-On recognizes existing local
operating system users. In addition, the user [e-mail] can log in to vCenter Single Sign-
On and vCenter Server as an administrator user. If your previous installation included an Active Directory
domain as an identity source, that identity source is still available after the upgrade. Because vCenter Server
supports only one default identity source, users might have to specify the domain when they log in
(DOMAIN\user).
Custom Upgrade
A custom upgrade might install different vCenter Server components on different machines or install a
second vCenter Server system on the same machine. You also use Custom Install to upgrade an
environment that is installed in different locations.
If you upgrade to vCenter Server 5.5 from a vCenter Server version that does not include vCenter Single
Sign-On, and you install vCenter Single Sign-On on a different machine than vCenter Server, vCenter Single
Sign-On does not recognize existing local operating system users. The user [e-mail] can
log in to vCenter Single Sign-On and vCenter Server as an administrator user. If your previous installation
supported Active Directory users, you can add the Active Directory domain as an identity source.
If you are upgrading vCenter Server from a version that includes vCenter Single Sign-On in multisite mode,
and if the different vCenter Server systems use Linked mode, you must resynchronize first. You can then
upgrade all vCenter Single Sign-On instances and maintain Linked Mode functionality. Linked Mode is
required for a single view of all vCenter Server systems. Multisite vCenter Single Sign-On is supported only
if all nodes are the same version.
If you are upgrading vCenter Server from a version that includes vCenter Single Sign-On in high availability
mode, you must upgrade all of the vCenter Single Sign-On high availability instances. Perform the upgrade
first, and configure high availability by protecting both vCenter Server and vCenter Single Sign-On with
VMware HA or VMware Heartbeat after the upgrade is complete.
NOTE When you install the vCenter Single Sign-On component that is included with vCenter Server version
5.5 in multiple locations, the VMware Directory Service is updated for all vCenter Single Sign-On instances
if you make a change in one location.
vCenter Single Sign-On Deployment Modes
vCenter Server provides several ways to deploy vCenter Single Sign-On to best serve your vSphere
environment
You can deploy vCenter Single Sign-On in one of three modes.
To choose the right mode for your environment, consider the way you use vCenter Server.
Table 3‑1. Choosing a vCenter Single Sign-On Deployment Mode
vCenter Server Deployment Single Sign-On Deployment Mode
Single vCenter Server Basic vCenter Single Sign-On
Multiple local vCenter Servers Basic vCenter Single Sign-On
Multiple remote vCenter Servers Basic vCenter Single Sign-On
Chapter 3 Preparing for the Upgrade to vCenter Server
VMware, Inc. 33