What’s a Backup Appliance?
The concept of a backup appliance is rooted in the same idea as your toaster. Your toaster has one job – it toasts. In this same sense, a backup appliance has one job – it performs backup. More precisely, a backup appliance functions more generally as a data protection appliance. A backup appliance is a form of computer appliance – which in the words of a Wikipedia definition is
A computer appliance is generally a separate and discrete hardware component specifically designed to provide a specific computing resource, and which often resides on a dedicated hardware platform.
Because data protection is a broad term, a backup appliance should be able to function in more than one role. The two primary roles for a backup appliance are functioning as an on-premise backup appliance and functioning as an off-premise backup appliance. An off-premise backup appliance is in essence a disaster recovery appliance. Both of these roles will be discussed in the next two sections.
On-Premise Backup Appliance
An on-premise backup appliance simply performs a backup through the LAN (Local Area Network) at a single location. This LAN is typically a 1Gbps Ethernet although higher- and lower-speed LANs may be used as well.
Off-Premise Backup Appliance (Disaster Recovery Appliance)
An off-premise backup appliance, which may also be known as a disaster recovery appliance, is typically the target for replication software that transfers in the least number of bytes possible enough information so that disaster recovery protection is offered.
When an off-premise backup appliance is used by a single entity, then this is typically referred to as a single tenant private cloud. When an off-premise backup appliance is offered as in an SaaS (Software as a Service) model – in essence, a disaster recovery service, it is typically referred to as multiple tenant public cloud.
For an example of the single tenant private cloud approach, see the vaulting versions of this backup appliance. For an example of a multiple tenant public cloud approach, see this offering - Vault2Cloud (cloud backup.)
A Third Role for a Backup Appliance: Cross-Vaulting
A third role for a backup appliance is to take the two roles already discussed and have them operate concurrently. This is particularly effective for putting a backup appliance into a ROBO (Remote Office Branch Office) or any entity with two or more branches. In this situation, the backup appliance simultaneously acts as a on-premise backup appliance and as an off-premise backup appliance.
An example of this can be seen on this backup appliance page for those backup appliances with a suffix of “cv” – which stands for cross-vaulting.
