• This article assumes that you have read the vSphere Upgrade Guide. This guide contains definitive information. If there is a discrepancy between the guide and this article, assume that the guide is correct.
• Because each environment is different, many upgrade decisions require knowledge and understanding beyond the scope of this article. For more information on your installation, see vSphere Upgrade Guide.
• Review the VMware vSphere 5.5 Release Notes for known issues or special installation notes.
• Operating systems prior to Windows 2008 are not supported for installing vCenter Server 5.5. A new installation of a supported operating system should be used, as upgrading is not supported. For more information, see VMware support for guest operating system upgrade (2018695).
• If the environment has SRM, replication needs to be disabled prior to running the upgrade.

• How vCenter Single Sign-On affects vCenter Server upgrades
• Hardware requirements for vCenter Server, the vSphere Web Client, vCenter Inventory Service, and vCenter Single Sign-On
• vCenter Server software requirements
• vSphere Web Client software requirements
• Identity Sources for vCenter Server with vCenter Single Sign-On
• Prerequisites for the vCenter Server Upgrade

How to vCenter Single Sign-On affects vCenter Server upgrades

• A Simple Install upgrade installs or upgrades a single vCenter Server and related components.
  
  
• If you upgrade to vCenter Server 5.5 from a vCenter Server version that does not include vCenter Single Sign-On, vCenter Single Sign-On recognizes existing local operating system users. In addition, the user [email protected] can log in as an administrator user to vCenter Single Sign-On and vCenter Server. If your previous installation supported Active Directory users, you can add the Active Directory domain as an identity source.
  
  
• If you upgrade vCenter Single Sign-On and vCenter Server, vCenter Single Sign-On recognizes existing local operating system users. In addition, the user [email protected] 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).
  
  
• For more information on the Simple Install upgrade, see Methods of upgrading to vCenter Server 5.5 on a Windows operating system (2053130).
  

• 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 [email protected] 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.
  
  
• For more information on the custom upgrade, see Methods of upgrading to vCenter Server 5.5 on a Windows operating system (2053130).

• Minimum hardware requirements for Simple Install deployment of vCenter Single Sign-On, the vSphere Web Client, vCenter Inventory Service, and vCenter Server
• Minimum hardware requirements for vCenter Single Sign-On, running on a separate host machine from vCenter Server
• Minimum hardware requirements for vCenter Inventory Service, running on a separate host machine from vCenter Server
• Minimum hardware requirements for vCenter Server
• Hardware requirements for VMware vCenter Server Appliance

• Installing vCenter Server on a network drive or USB flash drive is not supported.
• For the hardware requirements of your database, see your database documentation. The database requirements are in addition to the vCenter Server requirements if the database and vCenter Server run on the same machine.

Hardware Requirements for the vSphere Web Client server component

• vCenter Server requires the Microsoft .NET 3.5 SP1 Framework. If it is not installed on your system, the vCenter Server installer installs it. The .NET 3.5 SP1 installation might require Internet connectivity to download more files.
  
  
• If your vCenter Server host machine uses a non-English operating system, install both the Microsoft .NET Framework 3.5 SP1 and Microsoft .NET Framework 3.5 Language Pack through Windows Update. Windows Update automatically selects the correct localized version for your operating system. The .NET Framework installed through the vCenter Server installer includes only the English version.
  
  
• vCenter Server 5.5 removes support for Windows Server 2003 as a host operating system. For more information, see the VMware Compatibility Guide.
  
  
• vCenter Server 5.5 removes support for Windows Server 2008 SP1 as a host operating system. Upgrade Windows Server 2008 SP1 hosts to SP2 before upgrading vCenter Server to version 5.5. For more information, see the VMware Compatibility Guide and the Microsoft Software Lifecycle Policy.
  
  Note: The preceding link was correct as of September 19, 2013. If you find the link is broken, provide feedback and a VMware employee will update the link.
  
  
• If you plan to use the Microsoft SQL Server 2008 R2 Express database that is bundled with vCenter Server, Microsoft Windows Installer version 4.5 (MSI 4.5) is required on your system. You can download MSI 4.5 from the Microsoft Web site. You can also install MSI 4.5 directly from the vCenter Server autorun.exe installer.
  
  
• The VMware vCenter Server Appliance can be deployed only on hosts that are running ESX version 4.x or ESXi version 4.x or later.
  

vSphere Web Client software requirements

• For information about setting up and configuring syslog and a syslog server and installing vSphere Syslog Collector, see the vSphere Installation and Setup Guide.
• For related information on the above recommendations, see the Providing Sufficient Space for System Logging section in the vSphere Upgrade Guide.
  

Identity Sources for vCenter Server with vCenter Single Sign-On

vCenter Server version 5.1 and version 5.5 uses vCenter Single Sign-On for authentication. For a list of supported identity sources with vCenter Single Sign-On 5.1, see the vSphere 5 .1 documentation. vCenter Single Sign-On 5.5 supports the following types of user repositories as identity sources, but supports only one default identity source:

• Active Directory versions 2003 and later
  
  SSO allows you to specify a single Active Directory domain as an identity source. The domain can have child domains or be a forest root domain. This is shown as Active Directory (Integrated Windows Authentication) in the vSphere Web Client.
  
  
• Active Directory over LDAP
  
  SSO supports multiple Active Directory over LDAP identity sources. This identity source type is included for compatibility with the SSO service included with vSphere 5.1. This is shown as Active Directory as an LDAP Server in the vSphere Web Client.
  
  
• OpenLDAP versions 2.4 and later
  
  SSO supports multiple OpenLDAP identity sources. This is shown as OpenLDAP in the vSphere Web Client.
  
  
• Local operating system users
  
  Local operating system users are local to the operating system where the SSO server is running. The local operating system identity source exists only in basic SSO server deployments and is not available in deployments with multiple SSO instances. Only one local operating system identity source is allowed. This is shown as localos in the vSphere Web Client.
  
  
• vCenter Single Sign-On system users
  
  Exactly one system identity source named vsphere.local is created when you install Single Sign-On. This is shown as vsphere.local in the vSphere Web Client.
  

• For further information on identify sources, see the vSphere Installation and Setup Guide.
  

Prerequisites for the vCenter Server Upgrade

Before proceeding with the vCenter Server upgrade, ensure you prepare the vCenter Server system and the database.

Understanding and preparing for the upgrade

• vCenter Server 5.5 requires SSO and Inventory Service. Install or update these components in this order: vCenter Single Sign-On, the vSphere Web Client, Inventory Service, and vCenter Server. For more information, see the How vCenter Single Sign-On Affects vCenter Server Upgrade section in the vSphere Upgrade guide.
  
  
• Review the vSphere 5.5 Release Notes for known issues or special installation notes.
  
  
• See Update sequence for vSphere 5.5 and its compatible VMware products (2057795) for information on the sequence in which the vSphere 5.5 and its compatible VMware products need to be updated.
  
  
• If your vSphere installation is in a VMware View environment, see the Upgrading vSphere Components Separately in a Horizon View Environment section in vSphere Upgrade guide.
  
  
• Verify that your existing database is supported for the vCenter Server version that you are upgrading to. For more information, see the VMware Product Interoperability Matrix.
  
  
• Ensure that your vCenter Server database is prepared and permissions are correctly set. For more information about preparing vCenter Server databases, see the vSphere Installation and Setup guide.
  
  
• Close all instances of the vSphere Web Client.
  
  
• Stop the VMware VirtualCenter Server service.
  
  
• Run the vCenter Host Agent Pre-Upgrade Checker, and resolve any issues.
  
  
• Ensure that no processes are running that conflict with the ports that vCenter Server uses. For more information, see Required ports for vCenter Server 5.5 (2051575).
  

System Prerequisites

• Verify that your system meets the requirements listed in Hardware requirements for vCenter Server, the vSphere Web Client, vCenter Inventory Service, and vCenter Single Sign-On and vCenter Server software requirements.
  
  
• Ensure that the required ports are open. For more information, Required ports for vCenter Server 5.5 (2051575).
  
  
• If your vSphere system includes VMware solutions or plug-ins, ensure they are compatible with the vCenter Server version that you are upgrading to. For more information, see the VMware Product Interoperability Matrix .
  
  
• Before you upgrade any vCenter Server that belongs to a Linked Mode group, remove it from the Linked Mode group. Upgrading vCenter Servers that are members of a Linked Mode group can cause the upgrade to fail, and can leave vCenter Servers in an unusable state. After you upgrade all members of a Linked Mode group to version 5.5, you can rejoin them.
  
  
• If you do not intend to use evaluation mode, ensure that you have valid license keys for all purchased functionality. License keys from vSphere versions prior to version 5.0 are not supported in vCenter Server 5.x. If you do not have the license key, you can install in evaluation mode and use the vSphere Web Client to enter the license key later.
  
  
• Verify that the system on which you are upgrading vCenter Server is not an Active Directory primary or backup domain controller.
  
  
• Either remove any ESX Server 2.x or 3.x hosts from the vCenter Server inventory or upgrade these hosts to version 4.0 or later.
  
  
• Before you install or upgrade any vSphere product, synchronize the clocks of all machines on the vSphere network. For more information, see Synchronizing Clocks on the vSphere Network section in the vSphere Installation and Setup guide.
  
  
• Verify that the fully qualified domain name (FQDN) of the system where you will upgrade vCenter Server is resolvable. To check that the FQDN is resolvable, run this command in the command prompt:
  
  nslookup your_vCenter_Server_fqdn
  
  If the FQDN is resolvable, the nslookupcommand returns the IP and name of the domain controller machine.
  
  
• The installation path of the previous version of vCenter Server must be compatible with the installation requirements for Microsoft Active Directory Application Mode (ADAM/AD LDS). The installation path cannot contain non-ASCII characters, such as commas (,), periods (.), exclamation points (!), pound signs (#), at signs (@), or percentage signs (%). If your previous version of vCenter Server does not meet this requirement, you must perform a clean installation of vCenter Server.
  
  
• Back up your vCenter Server databases and SSL certificates
  
  
  • Take a full backup of the vCenter Server database and the vCenter Inventory Service database. For the vCenter Server database, see the vendor documentation for your vCenter Server database type. For the Inventory Service database, For more information, see Back Up the Inventory Service Database on Windows and Back Up the Inventory Service Database on Linux sections in the vSphere Installation and Setup guide.
  • If you are using MSQL Express database, please ensure that your database size is less than 10GB and that your backup can be restored.
    After the upgrade check the %temp%\VCDbUpgrade.log for any errors
    
    
  • Back up the SSL certificates that are on the vCenter Server system before you upgrade to vCenter Server 5.5. The default location of the SSL certificates is %allusersprofile%\Application Data\VMware\VMware VirtualCenter.
    
    
• Ensure that SSL certificate checking is enabled for all vSphere HA clusters. If certificate checking is not enabled when you upgrade, HA fails to configure on the hosts. For more information, see Configure SSL Settings in the Sphere Web Client in the vCenter Server and Host Management Guide.
  
  
• Ensure that all SSL certificates are still valid within the environment and have not yet expired. Default VMware Certificates are valid for 10 years, however, Certificate Authority (CA) signed certificates can very. If custom, CA signed SSL certificates have been used and need replacing, For more information, see Implementing CA signed SSL certificates with vSphere 5.x (2034833).
  
  
• If the vCenter Server 4.x environment that you are upgrading includes Guided Consolidation 4.x, uninstall Guided Consolidation before upgrading to vCenter Server 5.5.
  
  
• Before the vCenter Server installation, in the Administrative Tools control panel of the vCenter Single Sign-On instance to which you want to register vCenter Server, verify that these services are started:
  
  • VMware Certificate Service
  • VMware Directory service
  • VMware Identity Manager Service
  • VMware KDC service
  • tcruntime-C-ProgramData-VMware-cis-runtime-VMwareSTSService
    
    
• You must log in as a member of the Administrators group on the host machine, with a user name that does not contain any non-ASCII characters.
  
  
• The data migration tool is not supported for vCenter Server versions 5.1 and later. You cannot directly migrate an existing vCenter Server to a different machine during an upgrade to version 5.1.x or 5.5. You can migrate an existing vCenter Server to a different machine during an upgrade to version 5.0, and then perform an in-place upgrade from version 5.0 to version 5.1.x or 5.5.
  
  
  

Network Prerequisites

• Verify that DNS reverse lookup returns a fully qualified domain name when queried with the IP address of the vCenter Server. When you upgrade vCenter Server, the installation of the web server component that supports the vSphere Web Client fails if the installer cannot look up the fully qualified domain name of the vCenter Server from its IP address. Reverse lookup is implemented using PTR records. To create a PTR record, see the documentation for your vCenter Server host operating system
  
  
• If you use DHCP instead of a manually assigned (static) IP address for vCenter Server, ensure that the vCenter Server computer name is updated in the domain name service (DNS). Test this is by pinging the computer name. For example, if the computer name is host-1.company.com, run this command in the Windows command prompt:
  
  ping host-1.company.com
  
  If you can ping the computer name, the name is updated in DNS.
  
  
• Ensure that the ESXi host management interface has a valid DNS resolution from the vCenter Server and all vSphere Web Clients. Ensure that the vCenter Server has a valid DNS resolution from all ESXi hosts and all vSphere Web Clients.
  
  
• If you want to use Active Directory as an identity source, verify that it is set up correctly. The DNS of the SSO server host machine must contain both lookup and reverse lookup entries for the domain controller of the Active Directory. For example, pinging mycompany.com should return the domain controller IP address for mycompany. Similarly, the ping -a command for that IP address should return the domain controller hostname. Avoid trying to correct name resolution issues by editing the hosts file. Instead, make sure that the DNS server is correctly set up. For more information about configuring Active Directory, see the Microsoft Web site. Also, the system clock of the vCenter Single Sign-On Server host machine must be synchronized with the clock of the domain controller.

Prerequisites for all vCenter Server databases

• If your database server is not supported by vCenter Server, perform a database upgrade to a supported version or import your database into a supported version. See Supported Database Upgrades.
  
  
• If vCenter Server is using a database hosted on a Microsoft SQL Server with Windows Authentication, while the Profile Driven Storage service is configured to start with the local system account, manually reconfigure the service to run as a service account after upgrade or reconfigure the service before upgrade takes place . For more information see Profile Driven Storage service fails to start after upgrading to vCenter Server 5.5 (2081420)
  
  
• Perform a complete backup of the vCenter Server database before you begin the upgrade. To remove the DBO role, you can migrate all objects in the DBO schema to a custom schema. For more information, see Migrate objects from DBO schema to custom schema and add new roles instead of db_owner in MSDB and VCDB (1036331).
  
  
• You must have login credentials, the database name, and the database server name that will be used by the vCenter Server database. The database server name is typically the ODBC System database source name (DSN) connection name for the vCenter Server database.
  
  
• When you upgrade to vCenter Server 5.5, ensure that the upgraded version supports your database. For a list of the specific database versions supported for the version of vCenter Server that you are upgrading to, see the VMware Product Interoperability Matrix.
  
  Note: vCenter Server Appliance 5.5 uses a PostgreSQL for the embedded database. For external databases, the vCenter Server Appliance supports only Oracle databases, in the same versions shown in the VMware Product Interoperability Matrix for the version of vCenter Server that you are upgrading.

Prerequisites for Microsoft SQL databases

• To use a newly supported Microsoft SQL database, such as Microsoft SQL 2008, you do not need to perform a clean installation of vCenter Server if your existing database is also Microsoft SQL Server. For example, you can upgrade a Microsoft SQL Server 2000 database to Microsoft SQL Server 2005 or Microsoft SQL Server 2008 and then upgrade vCenter Server 4.0 or higher to vCenter Server 5.5. When you migrate the database from Microsoft SQL Server 2000 to Microsoft SQL Server 2005 or higher, set the compatibility level of the database to 90.
  
  
• JDK 1.6 must be installed on the vCenter Server machine. In addition, sqljdbc4.jar must be added to the CLASSPATH variable on the machine where vCenter Server is to be upgraded. If it is not installed on your system, the vCenter Server installer installs it. The JDK 1.6 installation might require Internet connectivity.
  
  
• Your system DSN must be using the SQL Native Client driver.
  
  
• Grant these permissions to the vCenter user in the vCenter Server database:
  
  GRANT ALTER ON SCHEMA :: <schema> to <user>;
  GRANT REFERENCES ON SCHEMA :: <schema> to <user>;
  GRANT INSERT ON SCHEMA :: <schema> to <user>;
  GRANT CREATE TABLE to <user>;
  GRANT CREATE VIEW to <user>;
  GRANT CREATE Procedure to <user>;
  
  Grant these permissions to the user in the MSDB database:
  
  GRANT SELECT on msdb.dbo.syscategories to <user>;
  GRANT SELECT on msdb.dbo.sysjobsteps to <user>;
  GRANT SELECT ON msdb.dbo.sysjobs to <user>;
  GRANT EXECUTE ON msdb.dbo.sp_add_job TO <user>;
  GRANT EXECUTE ON msdb.dbo.sp_delete_job TO <user>;
  GRANT EXECUTE ON msdb.dbo.sp_add_jobstep TO <user>;
  GRANT EXECUTE ON msdb.dbo.sp_update_job TO <user>;
  GRANT EXECUTE ON msdb.dbo.sp_add_category TO <user>;
  GRANT EXECUTE ON msdb.dbo.sp_add_jobserver TO <user>;
  GRANT EXECUTE ON msdb.dbo.sp_add_jobschedule TO <user>;
  

Prerequisites for Oracle databases

• To use a newly supported Oracle database, such as Oracle 11g, you do not need to perform a clean installation of vCenter Server if your existing database is also Oracle. For example, you can upgrade your existing Oracle 9i database to Oracle 10g or Oracle 11g and then upgrade vCenter Server 4.x to vCenter Server 5.5.
  
  
• The JDBC driver file must be included in the CLASSPATH variable.
  
  
• Either assign the DBA role or grant the following permissions to the user:
  
  grant connect to <user>
  grant resource to <user>
  grant create view to <user>
  grant create any sequence to <user>
  grant create any table to <user>
  grant create materialized view to <user>
  grant execute on dbms_job to <user>
  grant execute on dbms_lock to <user>
  grant unlimited tablespace to <user> # To ensure sufficient space
  
  After the upgrade is complete, you can optionally remove these permissions from the user profiles create any sequence and create any table.
  
  By default, the RESOURCE role has the CREATE PROCEDURE, CREATE TABLE, and CREATE SEQUENCE privileges assigned. If the RESOURCE role lacks these privileges, grant them to the vCenter Server database user.