Converting a SaaS application to a VMware virtual appliance can involve a lot of preparatory work before the application is ready to go into VMware Studio.
How long does it take to convert a SaaS application to a VMware virtual appliance?
If the Software as a Service (SaaS) application is already configured in a way that's compatible with virtual appliance architecture, a few clicks will convert it to a distributable template that can be used as a VMware virtual appliance. However, most developers want to convert applications that were never written for virtual appliance form, which takes a little more work.
More on VMWare virtual appliances
Understanding different types of virtual appliances
VMware's Virtual Appliance Marketplace
An application that wasn't originally written for the appliance format needs to be genericized, or stripped of all unique information. This will prepare the application and operating system for use as an appliance, or template.
Genericizing the operating system allows it to work in a dynamic environment. Ensure that the IP address selection is Dynamic Host Configuration Protocol, that it doesn't rely upon a fixed domain name system server and that the OS has been hardened and secured. That includes blocking non-essential traffic with the firewall, resetting remote-access applications to default passwords, requiring password changes on first login and flushing unnecessary users or testing configurations from the OS.
Genericizing the application is a similar process: First reset the configuration and access credentials, then secure the application down to the minimum required privilege settings. Next, create a wizard to allow people to set a password, configure additional users and define database backups. Finally, wipe out any licensing that was applied to the original application; the new wizard should ask for a new license if required.
Once you finish genericizing the OS and application, use VMware Studio to turn the virtual machine into a virtual appliance in a painless process. VMware Studio is a free tool that configures VMs, vApps and virtual appliances for VMware's hypervisor platforms, like vSphere and vCloud. You can create the virtual appliance in Studio via a command-line interface, Web interface or, for those using the open-source developer environment Eclipse, an Eclipse plug-in.
This was first published in June 2013