WebTitan - web filtering appliance

It is essential in this day and age, that organizations plan for the possibility of disaster. This is essential regardless of the size of the organization. In fact, it could be considered to be more important for smaller organizations as large companies have significant resources to specifically deal with redundancy, backup and disaster recovery. In contrast, smaller companies will often struggle with maintaining off-site backups for the different appliances deployed. Often, each appliance will have its own backup schema making automation difficult if not impossible and requiring specialist knowledge by the person tasked with maintaining backups.

A virtual appliance encapsulates all of the required "bits" for that server in an image file. It is possible to back up the image file on a nightly basis and to automatically copy the image to an off-site facility using the Internet. As the appliances within the organization become virtual, the mechanism for backing them up becomes standard across all appliances. Eventually, an automated task can perform the backup operation for all of the virtual images. In the event of a disaster, the image can be redeployed and the only loss to the organization will be the data produced since the last backup, which will often be inconsequential. By using virtual server images, the organization can even redeploy its server pool without needing to replace much hardware. Several companies offer a "hot standby" site which can be tailored to virtual server images, allowing staff to resume work almost immediately.

It is also far easier to manage duplicated server applications using virtual servers. If the organization has five or six server applications such as an email security gateway, web content filter gateway, CRM application and so on, replicating these applications can require five or six additional appliances. Using virtual servers, it is possible to replicate all of the server applications with as few as two physical systems.

Redundancy can also be a core requirement when an organization is geographically dispersed. Each branch office will require its own email security server, domain server and so on. Generally, distributing the applications to each of the remote offices will require a different appliance for each application. Virtualization is almost essential in this case as it allows each branch office to deploy a single hardware system with multiple virtual appliances instead of multiple physical appliances. The head office administrator can thus spread the virtual appliance suite based on each appliance and based on demand rather than on geography. New servers can be deployed and load-balanced with virtual machines at each outpost based purely on real time requirements.

Backing up a virtual image is relatively straightforward in comparison to backing up a live system disk. Being able to represent the entire system as a virtual image has many advantages, particularly in terms of nightly backups or in the event of a restore from archive. Should a given system fail, which is not at all unusual, the images which were backed up can be immediately redeployed on another virtual machine with little or no down-time. Another virtual server can be quickly instantiated with the saved image. By using virtual appliances, the availability of the system can be maintained without the need for expensive, redundant appliances or systems. Once the server has been repaired or replaced, the virtual machines can again be migrated off the temporary server with the minimum of fuss or down-time. Take for example the case where the branch office is in Hawaii and the head office is in San Francisco. If the server in Hawaii breaks down, the administrator in head office can relocate the virtual appliance images to another  server, possibly even in another location such as the LA office. He or she can also arrange for a local supplier to provide a new server to the Hawaii office or to repair the existing server. Once the server is once again available, the virtual appliance image  can be migrated back to the Hawaiian office again with no down-time and no expensive travel time.