The Future

Physical backup and restore has been ignored for a long time. With file systems continuing to increase in size exponentially, the ability of a physical backup strategy to scale with increasing disk bandwidth makes it an interesting strategy. In the WAFL context, where snapshots provide the ability to discover recently changes blocks very efficiently, incremental image backups become a possibility. We are working on an implementation of incremental backup and will soon be able to answer questions about its performance. The image dump/restore technology also has potential application to remote mirroring and replication of volumes.