When upgrading to vSphere 6.5, it is important to understand changes in component behavior for version 6.5 that can affect the upgrade process.

Understanding changes from previous versions of vSphere can assist in your upgrade planning. For a complete list of new features in vSphere 6.5, see the Release Notes for version 6.5 releases.

vCenter Server Upgrade Methods

vSphere supports multiple methods for upgrading vCenter Server to version 6.5.

Supported Migration Path from vCenter Server for Windows to vCenter Server Appliance
You can migrate from an existing vCenter Server for Windows configuration to a vCenter Server Appliance 6.5 deployment using a graphical user interface-based installer or a command line interface-based installer. See Differences between Upgrading and Migrating vCenter Server on Windows.
Support for Command Line Interface (CLI) Deployments of vCenter Server Appliance
You can upgrade an existing vCenter Server Appliance deployment to version 6.5 using a CLI. See CLI Upgrade of the vCenter Server Appliance and Platform Services Controller Appliance.
VMware Update Manager Changes
You can use a graphical user interface (GUI) when upgrading vCenter Server deployments using VMware Update Manager.
Simple Upgrade Process from vCenter Server 5.5 Replaced
Upgrading from vCenter Server 5.5 to vCenter Server 6.5 with an embedded Platform Services Controller instance replaces the vCenter Server5.5 simple upgrade process. The upgrade process migrates your vCenter Server 5.5 services to a vCenter Server 6.5 deployment with an embedded Platform Services Controller instance.
Custom Upgrade Process from vCenter Server 5.5 Replaced
Upgrading from vCenter Server 5.5 to vCenter Server 6.5 with an external Platform Services Controller instance replaces the vCenter Server 5.5 Custom or separate upgrade process. When you upgrade your custom or distributed vCenter Server 5.5 instance, the upgrade process includes any vCenter Server 5.5 services that are deployed separately from vCenter Server. You do not need to upgrade them separately.
During the process of upgrading to vCenter Server 6.5 with an external Platform Services Controller deployment, any vCenter Server 5.5 services that are deployed on a separate VM or physical server from the vCenter Server are migrated to the same VM or physical server as the vCenter Server instance. vCenter Server components can no longer be deployed individually. For more details on service migration during upgrade, see Distributed vCenter Server 5.5 for Windows Services Relocation During Upgrade or Migration
Upgrade Order and Mixed Version Environment Behavior
You cannot upgrade multiple vCenter Server instances or Platform Services Controller instances concurrently, and upgrade order matters. See Upgrade or Migration Order and Mixed-Version Transitional Behavior for Multiple vCenter Server Instance Deployments.

Changes in Supported Deployment Types

Changes from previous versions of vSphere can affect your deployment type.

VMware Platform Services Controller Changed from vCenter Server 5.5
The VMware Platform Services Controller contains common infrastructure services such as vCenter Single Sign-On, VMware certificate authority, licensing, and server reservation and registration services.
You can deploy a Platform Services Controller instance on the same virtual machine (VM) or physical server as vCenter Server, which is vCenter Server with an embedded Platform Services Controller instance. You can also deploy a Platform Services Controller instance on a separate machine or physical server, which is vCenter Server with an external Platform Services Controller instance.
vCenter Server Component Services Deployment Changed from vCenter Server 5.5
vCenter Server component services are deployed in either the vCenter Server or Platform Services Controller group of services. vSphere common services can no longer be upgraded individually.
vCenter Server 5.5 services that are deployed individually before the upgrade are migrated to the appropriate service group during the upgrade process. The upgrade software migrates, upgrades, and configures existing vCenter Server 5.5 services as needed.
For more details about service deployment, see About the vCenter Server for Windows Upgrade Process.
Enhanced Linked Mode Topology Changes from vCenter Server 5.5
The implementation of Linked Mode has changed starting with vSphere 6.0. You no longer need to join vCenter Server instances to Linked Mode groups. You can access the replication functionality provided by Linked Mode in vSphere 5.5 by registering multiple vCenter Server instances to the same Platform Services Controller or joining Platform Services Controller instances in the same vCenter Single Sign-On domain.
To enable high availability between the vCenter Server instances in a single vCenter Single Sign-On domain, the vCenter Server instances must use the same site name.

Unlike the original Linked Mode, Enhanced Linked Mode is available and supported on vCenter Server on Windows and vCenter Server Appliance.

Topology Changes After Upgrade or Migration
You can change your deployment topology after upgrade or migration to vCenter Server 6.5. You cannot change your deployment type during upgrade or migration. For information on supported topology changes, see Changing a vCenter Server Deployment Type After Upgrade or Migration.

Mixed IPv4 and IPv6 Upgrade and Migration

  • Upgrade and migration from vCenter Server 6.0 to 6.5 is supported for pure IPv4 or pure IPv6 management networks only.
  • Upgrade and migration from vCenter Server 5.5 to 6.5 supports only IPv4. You can reconfigure the target deployment to IPv6 after upgrading or migrating.
  • Upgrade and migration from a mixed mode IPv4 and IPv6 environment transfers configurations depending on the source deployment configuration.
    Table 1. Transfer of networking configuration settings for mixed mode IPv4 and IPv6 deployments
    Source configuration Settings transferred during upgrade or migration Settings not transferred during upgrade or migration
    DHCPv6 and AUTOv6 DHCPv6 AUTOv6
    DHCPv4 and DHCPv6 DHCPv4 DHCPv6
    DHCPv4 and AUTOv6 DHCPv4 AUTOv6
    DHCPv4 and Static IPv6 Static IPv6 DHCPv4
    Static IPv4 and AUTOv6 Static IPv4 AUTOv6
    Static IPv4 and DHCPv6 Static IPv4 DHCPv6
    Static IPv4 and Static IPv6 Static IPv4 and Static IPv6 -

Changes Affecting VMware Services

Changes affecting VMware services may affect your upgrade planning.

Embedded PostgreSQL Database Replaces Embedded Microsoft SQL Server Express Database for vCenter Server 6.0
The vCenter Server 6.0 embedded Microsoft SQL Server Express database is replaced with an embedded PostgreSQL database during the upgrade to vCenter Server 6.5. The maximum inventory size that applied for Microsoft SQL Server Express still applies for PostgreSQL.
vCenter Inventory Services Removed for vCenter Server 6.5
vCenter Inventory Services are no longer needed for vCenter Server 6.5. The upgrade process migrates the data and removes the vCenter Inventory Services.
Using Oracle for vCenter Server External Database
For information about supported database server versions, see the VMware Product Interoperability Matrix at http://www.vmware.com/resources/compatibility/sim/interop_matrix.php.
VMware vSphere Syslog Collector
Starting with vCenter Server 6.0 for Windows, vSphere Syslog Collector is included in the vCenter Server group of services. vSphere Syslog Collector continues to function exactly as for vCenter Server 5.5. However, it is no longer used for vCenter Server Appliance.
VMware Syslog Service
Starting with vCenter Server Appliance 6.0, vSphere Syslog Service is a support tool for logging that is included in the vCenter Server group of services.