Serverless backup is a method of offloading backup procedures from a server so that the time ordinarily devoted to backup functions can be used to carry out other server tasks. Ordinarily, the amount of time that a server can devote to processing requests from applications is limited by the backup window - the amount of time that must be reserved for data backup. Serverless backup is a storage area network (SAN) solution that is designed to lead to lower hardware costs and improved time-effectiveness, scalability, and fault tolerance. A number of companies, including Legato, Veritas, EMC, and Computer Associates offer or are developing serverless backup products.
Serverless backup enables disk-to-tape or disk-to-disk backup without depending on server resources or network bandwidth. The Legato, Veritas, and CA products are based on a process known as disk imaging. These applications use an intelligent agent, which makes a snapshot copy of pointers to the data. The snapshot copy consists of an image of the pointers, which indicate the location of the data. The intelligent agent and backup procedures communicate through the Network Data Management Protocol (NDMP). The EMC version is based on something called a Fastrax data movement platform and Hewlett Packard's OpenView OmniBak II backup application. Proprietary software within the hardware platform is used, first, to mark logical backup objects, and then to back up data on the list.