Over the past few years hardware appliances have become the preferred form factor for deploying specialized IT solutions. Appliances are preconfigured, easy to deploy and simple to manage, and usually offer a compact form factor.
However, the rapid adoption of appliances, particularly for security solutions, has led to appliance bloat -- racks of multicolored boxes, each performing a specialized function. As enterprises deploy more appliances, the ease-of-use and management benefits that make security appliances popular are at risk of being overwhelmed by the complexity and cost involved with managing a large number of point solutions.
One solution is to use virtual appliances. They let enterprises install hardware-free appliances on existing virtualized server infrastructure. Virtualization technology, such as that of VMware, transforms a mix of industry-standard x86 servers and their associated processors, memory, disk and network components into a pool of logical computing resources that can be dynamically allocated to different virtual machines (each of which might be running an entirely different operating system, applications and services).
Commercial virtual appliances are just starting to appear. VMware's virtual appliance marketplace lists commercial virtual appliances certified to meet VMware's production-ready criteria.
Many of today's hardware appliances are based on standard x86 server hardware running a customized operating system and specialized applications that lend themselves well to transformation into a virtual appliance. Everything about a virtual appliance -- operating system, application, user interface -- is the same as with a physical appliance, except that it requires no dedicated, physical infrastructure.
The benefits are the same as those realized by traditional server virtualization -- server and storage capacity can be increased without investing in additional hardware -- but virtual appliances can also take advantage of the data center's virtualized failover, backup, change management and disaster recovery features, generating further efficiencies. In addition, virtual servers can be deployed for scalability or redundancy purposes on an as-needed basis at zero incremental cost.
Virtual appliances offer many additional benefits, including:
* Streamlined product evaluations: Instead of waiting to get hardware in-house for evaluation, you can download a trial virtual appliance and begin using it in a matter of hours without having to interact with the vendor or reseller.
* Simpler, more powerful lab environments: Virtual appliances make it easy to set up multiple appliances on a single server for testing purposes. You can try new products and modules, test configuration changes and evaluate different server configurations. You also can take a snapshot of your production environment and run it in a lab environment. Applying patches and upgrades can be performed at low cost in the lab environment on an identical snapshot of your production system.