VCenter Server is the central management component in a vSphere environment. Without vCenter Server, ESX and ESXi hosts are simply hypervisors with the ability to run virtual machines, commonly referred to as guests. When coupled with appropriate host licensing, vCenter Server can significantly extend the capabilities of the ESX and ESXi hosts it manages. Some of the extended capabilities that vCenter Server includes are VMotion, Storage VMotion, High Availability, and Distributed Resource Scheduling. Keep in mind that vCenter Server does not enable these features but rather leverages these capabilities when hosts are assigned licenses that include those features. You should become familiar with vCenter Server's requirements as well as the proper installation method. A well-configured vCenter Server installation provides a solid administrative platform to manage vSphere to its fullest potential.
Prepare for Installation
One of most important components of the vSphere environment is vCenter Server. vCenter Server acts as a central management point for managing ESX and ESXi hosts, and additional components like the Guided Consolidation Service, vCenter Update Manager, and user permissions. Installing vCenter Server can be broken into three steps.
- Ensure that your system is capable of running vCenter Server.
- Install vCenter Server and any additional components.
- Perform basic configuration of vCenter Server and some additional components.
As of this writing, vCenter Server is available only for Microsoft Windows systems. This has been a sore subject for administrators in IT shops that primarily run operating systems other than Windows. VMware has listened, and currently there is a technical preview of vCenter Server for Linux, available for download at http://www.vmtn.net/ as a virtual appliance.
vCenter Server must operate on the Microsoft Windows platform. What else does it require? To ensure that vCenter Server can accommodate the performance necessary to efficiently manage ESX and ESXi hosts, VMware has provided some preliminary requirements for the hardware, operating system, and database required to support vCenter Server.
Identify Hardware Requirements
VMware vCenter Server can be installed on a physical or virtual machine that meets the requirements listed in Table 3.1
Table 3.1: Hardware Requirements
|Processor||2.0GHz or greater Intel or AMD x86 based processor. It is a best practice to use a faster processor if the vCenter Database runs on the same server.|
|Memory||2GB of RAM. Again, it is a best practice to use more RAM if the database
is running on the same server.
The VMware vCenter Management Webservices require from 128MB to 1.5GB of additional memory. The memory is allocated at system startup.
|Database||A minimum of 1GB of additional storage is required in addition to the
storage required for the operating system installation.
If the VMware vCenter Update Manager service is installed on the same
system, an additional 22GB of space is required to accommodate storage
If Microsoft SQL Server 2005 Express is installed as the database, 2GB of disk space is required during the installation, with 1.5GB reclaimed after the installation is complete.
|Networking||A 100MB network connection can be used, but a 1GB network connection is recommended.|
Meeting these requirements will ensure proper operation of vCenter Server and any additional components. When designing the environment, give additional thought to future growth or scalability of vCenter Server.
Identify Operating System Requirements for vCenter Server and vSphere Client
Due to the fact that vCenter Server was developed to operate on a Windows platform, VMware supports this product on only a limited number of operating system configurations. Some operating systems, such as Windows 2000, are no longer supported, or are referred to as end of life, while others, such as 64-bit versions, are not yet supported 100 percent natively. Additionally, some operating systems were not originally designed for this type of workload, such as Windows 2003 Web Edition. Table 3.2 lists the operating systems for which VMware vCenter Server is supported, their versions, and supported Internet Protocol modes.
Table 3.2: Operating System Requirements for vCenter Server
|Windows XP Pro (SP2 or greater, x86)||Yes||Yes|
|Windows 2003 Server (SP1 or greater x86)||Yes||Yes|
|Windows 2003 Server R2||Yes||Yes|
|Windows 2003 Server x64||Yes||Yes|
|Windows Server 2008 x86||Yes||Yes||Yes|
|Windows Server 2008 x64||Yes||Yes||Yes|
VMware has tested the operating systems in Table 3.2 and certified their use for vCenter Server. Older operating systems, such as Windows NT 4.0, Windows 2000, and Windows 2003 without any service pack, have failed to meet the minimum requirements of vCenter Server.
To manage VMware vCenter Server, you use vSphere Client to configure, manage, and monitor the environment. vSphere Client was developed using Microsoft .NET technologies and is also limited to Microsoft operating systems. Table 3.3 lists the operating systems on which vSphere Client may be installed to manage a vCenter Server.
Table 3.3: vSphere Client System Requirements
|Windows XP Pro (SP2 or greater, x86)||Yes||No||Yes|
|Windows 2003 Server (SP1 or greater x64)||Yes||No||Yes|
|Windows 2003 Server (SP1 or greater x86)||Yes||No||Yes|
|Windows 2003 Server R2||Yes||No||Yes|
|Windows 2003 Server x64||Yes||No||Yes|
|Windows 2003 Server Standard and Web Edition x86 or x64||Yes||No||Yes|
|Windows Vista Business with SP1||Yes||Yes||Yes|
|Windows Vista Enterprise with SP1||Yes||Yes||Yes|
|Windows Vista Business with SP1 x64||Yes||Yes||Yes|
|Windows Vista Enterprise with SP1 x64||Yes||Yes||Yes|
|Windows Server 2008 x86||Yes||Yes||Yes|
|Windows Server 2008 x64||Yes||Yes||Yes|
There are also some best practices with regard to the domain membership of a server running vCenter Server. Following these guidelines will ensure installation and operation run more smoothly:
- Microsoft strongly recommends that vCenter Server be joined to a Microsoft Windows domain. This will provide better security and domain capabilities to services that require it.
- vCenter Server 4.0 adds the ability to use distributed vCenter Servers, referred to as Linked Mode vCenter Servers. If you are using Linked Mode vCenter Servers, the individual vCenter Servers may be in different domains, provided there is a two-way trust between the two domains.
In addition to vSphere Client, vSphere Web Access may be used to manage the vCenter Server installation, and it has some minimum requirements as well. The following browsers have been tested by VMware to verify proper operation of vSphere Web Access:
Microsoft Windows Internet Explorer 6.x
Microsoft Windows Internet Explorer 7.0
Mozilla 1.x for Windows/Linux
Mozilla Firefox 2.0.x
Mozilla Firefox 3.0.x
Ensuring that the hardware and software requirements are met will ensure that the configuration used for vCenter Server, vSphere Client, and vSphere Web Access will provide a trouble-free installation and management platform for the vSphere environment.
Identify Database Requirements
At the heart of VMware vCenter Server and its ancillary components lie a number of databases. Separate databases are recommended for vCenter Server and ancillary components, such as vCenter Update Manager, although it is not required for each additional component to be installed using a separate database. Separate databases add levels of separation of the data and can result in better performance levels. These databases do not have to be on the same machine as vCenter Server, nor do they have to reside on the same remote server. It is possible to have a vCenter instance installed on one server, with its SQL database residing on another server, while having the vCenter Update Manager database on a third server. The choices are wide and depend on your operational needs. The default installation will load vCenter and required databases on the same system. The vCenter Server installation routine includes Microsoft SQL Server 2005 Express Edition.
If you accept the defaults, the instance of Microsoft SQL Server 2005 Express that is bundled with vCenter Server is used, and user authentication defaults to the rights of the user account performing the installation. If another supported database is used, administrative credentials are required.
Note: Although not required, as a best practice, ensure that the database service on either the local or remote machine is also running as a domain account to aid in authentication if you are using any edition of Microsoft SQL Server 2005.
The following databases are supported for vCenter Server and vCenter Update Manager installations.
- Microsoft SQL Server 2005 Express
- Microsoft SQL Server 2005 Standard Edition SP2
- Microsoft SQL Server 2005 Enterprise Edition SP2
- Microsoft SQL Server 2005 Enterprise Edition SP2 x64
- Microsoft SQL Server 2008 Standard Edition
- Microsoft SQL Server 2008 NN Enterprise Edition
- Microsoft SQL Server 2008 Enterprise Edition x64
- Oracle 10g Standard Edition, Release 1 (10.1.0.3.0)
- Oracle 10g Enterprise Edition, Release 1 (10.1.0.3.0)
- Oracle 10g Standard Edition, Release 2 (10.2.0.1.0)
- Oracle 10g Enterprise Edition, Release 2 (10.2.0.1.0)
- Oracle 10g Enterprise Edition, Release 2 (10.2.0.1.0) x64
- Oracle 11g Standard Edition
- Oracle 11g Enterprise Edition
Identify Networking Requirements
Because vSphere is not a single stand-alone server, application, or isolated computing system, the pieces of the puzzle will require some form of communication between them. There are many possible configuration scenarios depending on the environment in which vSphere is being deployed.
A vCenter Server must be able to communicate with each host and each vSphere client. Furthermore, if a remote database server is utilized rather than a local instance of the database, the required TCP/IP ports for that database installation are also required.
If an instance of vCenter Server is installed on Windows Server 2008, you must either disable the Windows Firewall or make an exception to allow communication between all of the required pieces of the environment.
vCenter Server requires several ports to be open when you select a default installation. Each of these ports will be used for a different portion of the overall communications path. To enable proper communication between each of the components, consult a network engineer to ensure the appropriate ports are open for communication.
Web ports that are required to be open include the following:
- Port 80 is required for the purpose of redirecting nonsecure requests to vCenter Server on a secure port.
- Port 443 is the default port used to communicate with vSphere Client and to look for data from vSphere Web Access Client and other VMware Software Development Kit (SDK) applications such as the VI Toolkit. You can change this port, but vSphere Client and any SDK applications must use the vCenter Server name, followed by the nondefault port number.
- Port 8080 is the port used by Web Services HTTP.
- Port 8443 is the port used by Web Services HTTPS.
Directory Services ports that are required to be open include the following:
- Port 389 is the standard port number used for Lightweight Directory Access Protocol (LDAP) services. This port is used for the Directory Services component of vCenter Server. It must be available to vCenter Server, even if vCenter Server is not part of a Linked Mode Group. You can change from port 389 to any available port ranging from 1025 to 65535. This is the normal LDAP port that the vCenter Server Active Directory Application Mode (ADAM) instance listens on.
- Port 636 is also used when using vCenter in Linked Mode. This is the Secure Sockets Layer (SSL) port of the local vCenter Server ADAM Instance. It is the preferred port number, but it can also be changed to any available port ranging from 1025 to 65535.
Host and client ports that are required to be open include the following:
- Port 902 is used for multiple tasks. It is used to manage ESX and ESXi hosts and send data to them. vCenter Server also receives a heartbeat at regular intervals from hosts on port 902 over User Datagram Protocol (UDP). This port must not be blocked between vCenter Server and hosts, or between hosts. Port 902 is also used for providing remote console access to virtual machines from vSphere Client.
- Port 903 is used in the same fashion as 902: it provides remote console access of virtual machines to vSphere Client. These ports must be open for proper communication to occur between vCenter Server and vSphere Client, as well as from vSphere Client and the ESX and ESXi hosts.
Identify Authentication Requirements
Initial authentication in vCenter Server is handled through local user accounts on the system that vCenter Server is installed on. Authentication to managed ESX and ESXi servers is handled through vCenter Server as hosts are added to the vSphere configuration. Additionally, local accounts on each host may be created. Accounts local to ESX and ESXi hosts do not have permissions in the vCenter Server interface, even though they may have elevated privileges at the host level.
Installing and Configuring vCenter Server
VCenter Server installation requirements
VCenter database installation in SQL Server 2005, Oracle
VCenter Server installation steps and components
Printed with permission from Wiley Publishing Inc. Copyright 2009. VMware vSphere 4 Administration Instant Reference by Scott Lowe, Jason W. McCarty and Matthew K. Johnson. For more information about this title and other similar books, please visit Wiley Publishing Inc.
This was first published in June 2010