What is a Software Appliance?

A new breed of appliance is emerging. Not unlike their kitchen counterparts, the goal in using these appliances is to plug them in and use them, not to spend hours installing them, configuring them, tuning them and maintaining them.

These appliances are built using software.

Software Appliances

Software appliances are a hot topic. Many consider them a significant trend in the technology industry. Leading the trend, Red Hat recently announced an Appliance Operating System, based on our proven Red Hat Enterprise Linux (RHEL) and virtualization support, that promises to simplify the effort required to deploy and maintain software appliances in production.

A further benefit is that your software supplier may assume responsibility for updating not only their packages, but the entire operating environment for the application, thereby removing that burden from your Information Technology staff. In the future, you’ll be able to move these standard appliances among machines while they are in use, even moving them into a "cloud" computing environment provided on the Internet, thus providing capacity on demand as well as disaster recovery capability.

Evolution of Computer Appliances

Past computer appliances have included custom chipsets and hardware with proprietary operating systems, such as routers. Other examples include applications bundled with hardware and software in a "sealed" configuration, such as firewalls, file servers, email filters and search appliances.

The virtual appliance takes the concept a step further and bundles the operating system with the application and other services in a single package. Virtualization technology enables the package to run on a variety of platforms supporting virtual machines and to share hardware with other appliances.

Red Hat’s Implementation

Red Hat will provide a software development kit and Appliance Operating System for Independent Software Vendors (ISVs), enabling them to configure their application, the middleware and the operating system as a single unit in the form of a system image. This image can be executed as a virtual client in multiple virtualized environments, including those provided by RHEL, VMware, Amazon (EC2), Microsoft’s Viridian (when available) and SUN.

Since the development kit is based on RHEL, certified applications will run unchanged on the Appliance Operating System. Application and system updates can be delivered as a unit, rather than as a rebuild, reinstall, or complex upgrade. Other benefits for ISVs include reduced development costs and reduced support costs, advantages they can pass on to their customers.

Future Applications

Appliance operating systems promise great benefits in those environments in which stability is preferred, low service costs are required, and applications are not changing rapidly. An example is a small business or branch office environment. Using appliances, a firewall, router, file server, backup suite, and accounting package can share a single hardware platform. Each application can be encapsulated in its own virtual machine and serviced and maintained using a replacement strategy, rather than a reintegration at the local server.

This approach enables the timing of the various system upgrades to occur on different schedules and serves to limit integration testing requirements. It also enables different applications to use different versions or patch levels of the operating system without causing conflicts. The encapsulation provided by the virtual hypervisor will even allow different operating systems to co-reside on the server: a Linux operating system and application can easily coexist with a Windows operating system and application.

Next Steps for CIOs

If you are the Information Technology leader for a small or medium sized business, ask your software vendors whether they are considering an appliance strategy for their applications. Using software appliances could make both your application deployment and ongoing support easier and simpler. Think about how virtual appliances could simplify some of the operational issues you face. Consider how appliances will allow you to access applications that aren’t available on the operating system you are using today. Or, how appliances may allow you to extend the life of applications that are nearing the end of support on available hardware.

CIOs in larger enterprises should be asking their architects and software developers the same questions. Consider which of your internally developed and deployed applications could benefit from an appliance strategy.

The Red Hat Appliance Operating System is expected in the first half of 2008. Availability will be announced on www.redhat.com. Interested ISVs and others should contact appliance-info@redhat.com.