What is a virtual appliance?
A virtual appliance is a virtual machine (VM) that a developer or application software vendor has optimized to include only the application and the OS components that are needed to run it. Going one step further, a VMware virtual appliance is any virtual appliance that runs on a VMware hypervisor. This distribution model ensures that the appliance provides a uniform and stable platform, thus simplifying testing, deployment and support.

The following steps will help you select, download and start an appliance using the VMware Virtual Appliance Marketplace, the company’s online virtual appliance store.

  1. Identify an appliance-hosting platform
    Think of the VMware virtual appliance as a prepackaged VM. You will need a physical machine as well as a hypervisor to host the VM. You can run virtual appliances on VMware’s vSphere, Workstation, Player and Fusion.
  2. Find VMware virtual appliances
    You can locate an appliance based on functionality, OS or application vendor. You can search for appliances directly at the VMware Virtual Appliance Marketplace or through your vSphere Client or Workstation management interface. The VMware Virtual Appliance Marketplace lists nearly 2,000 different appliances, and the number continues to grow. VMware’s site also allows users to post reviews of appliances, although the number of reviews is rather limited, which seems to be a weakness. Hopefully, with time, more reviews will be available to assist users with selecting appliances and help application vendors improve their products.
  3. Download the VMware virtual appliance
    Some appliances, such as the vSphere Management Assistant are available directly from VMware’s website. Other virtual appliances will force a redirect to the vendor’s website for downloading or registration. Some appliances are only available as torrents, which point to a target file, so you may need to install a BitTorrent client.
    Most appliances will come preconfigured with a default username and password, which you can typically find on the download page. The supplied credentials will allow you to access the VMware virtual appliance once it is running, so you can then create your own accounts. It is also important to pay attention to any licensing restrictions, such as the evaluation duration, that a vendor imposes on either the appliance’s OS or installed applications.
  4. Extract and install
    Once you have downloaded a VMware virtual appliance, it is time to install it. You will likely  download the file in a compressed format, such as .7z or .zip, that you will need to extract with  the appropriate utility. You are ultimately looking for a VMX (configuration file) or OVF file (Open Virtualization Format). This is the file you will select to start the appliance.
  5. Start it up the VMware virtual appliance
    Now for the fun part: powering it on. One of the great things about VMware virtual appliances is your ability to test them and tweak the settings, without worrying about breaking them since you can start over with a clean appliance. Did you download a Linux distro, but aren’t too thrilled with it? Dump it and download another appliance that better suits your needs.
    The ease of using appliances can allow you to focus on getting the absolute best tools, without investing large amounts of time to build the whole environment, only to find out it isn’t what you had hoped.

VMware vCenter Server Appliance is a tool for managing a virtual environment.