POINT-IN-TIME COPY WITH CHAIN CLONING

摘要

A method and system for storage copy with chain cloning are provided, including providing a volume with one or more snapshots in the form of a dependency chain, where the volume and one or more snapshots are volume nodes in the dependency chain and providing associated metadata required to maintain the one or more snapshots; cloning the dependency chain to create at least one a sparse copy chain including sparse copies of the volume and the one or more snapshots resulting in sparse volume nodes, resulting in a lattice structure of the dependency chain of volume nodes and one or more sparse copy chains of cloned volume nodes.

主权项

1. A method for storage copy with chain cloning, comprising:
providing a volume with one or more snapshots in the form of a dependency chain, wherein the volume and one or more snapshots are volume nodes in the dependency chain and providing associated metadata required to maintain the one or more snapshots; cloning the dependency chain to create at least one a sparse copy chain including sparse copies of the volume and the one or more snapshots resulting in sparse volume nodes, resulting in a lattice structure of the dependency chain of volume nodes and the at least one or more sparse copy chain of cloned volume nodes; defining mappings to a volume node from source and target volume nodes in the dependency chain and sparse source and sparse target volume nodes in the at least one sparse copy chain; and defining metadata for each volume node including a state indicating if the data is on the target volume node and a high water mark to indicate which of the dependency chain and at least one sparse copy chains to go to if it is not on the target volume node.