Both vCenter Server and the vCenter Server Virtual Appliance (vCSA) provide centralized management of vSphere deployments...
in the enterprise. Despite performing the same function, however, the two do not install similarly, nor do they support the same features.
There is no clear-cut answer to which the better choice is for your VMware shop, but you can make a more informed decision by reading up on the pros and cons of the full version of vCenter Server and vCSA.
Limitations to the vCenter Server Virtual Appliance
The VMware vCenter Server Virtual Appliance installs on SUSE Linux Enterprise Server for VMware, a free version available to anyone with a vSphere license. VCSA versions 5.0.1 and later run a PostgreSQL database as opposed to the IBM DB2 database used in previous versions. VCSA only supports the PostgreSQL database, so if Microsoft SQL Server or IBM DB2 would more easily integrate in your infrastructure, vCSA is not your best bet.
The vCSA also does not support Linked Mode, a feature in which multiple instances of vCenter Server are linked together to manage massive environments. A single instance of vCenter Server can manage up to 300 hosts and 3,000 virtual machines (VMs). In Linked Mode, you can manage up to 1,000 hosts and 10,000 VMs across 10 vCenter Server instances. This setting also allows you to create global definitions for administration roles and search for inventory items across multiple vCenter Server instances.
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In addition, vCSA does not offer support for IPv6, though this feature is not as widely used as Linked Mode. Support does not change even if the appliance runs on top of SUSE Linux, an operating system that, by default, supports IPv6.
VMware vCenter Server vs. vCSA: Installation
After reading about the features vCSA does not support, you might be inclined to start with a full installation of vCenter Server. However, it is easier to install the vCSA than the full version.
Start by downloading the .VMDK and .OVF files for the appliance onto your computer. Next, from the vSphere Client, simply deploy vCSA by selecting the "Deploy OVF Template" option from the file menu.
The full version of vCenter Server does support more databases, Linked Mode and IPv6, but installation is a lengthier process that comes with more prerequisites. You first need a 64-bit installation of Windows Server 2008 R2 with a supported database, such as Microsoft SQL Server Express. There are other requirements, such as the Microsoft .NET 3.5 SP1 Framework or the Microsoft Windows Installer version 4.5. Finally, you need either a physical or a virtual server on which to install vCenter Server.
The bottom line
If you're looking for an easy way to get started with vCenter Server, look no further than the virtual appliance. Even though it runs on top of Linux, you don't have to be a Linux expert to master vCSA. Once deployed, the appliance offers an easily accessible interface that leads you through all the configuration steps.
On the other hand, you can manage a larger VMware environment with vCenter Server using Linked Mode. As such, the size of your data center may be the most compelling reason to opt for the full installation or the virtual appliance.