Patent ID: 7996636

Claim:
A computer-implemented method, comprising: assigning, by a processor executing a storage operating system of a computer, a first unique buffer tree identifier (bufftree ID) to a first volume of the computer and assigning a second unique bufftree ID to an ancestor volume of the first volume; accessing a data block of the first volume by the storage operating system, and in response, determining whether a data ID of the data block matches an expected data ID for the first volume; if the data ID of the data block matches the expected data ID, determining whether a volume ID of the data block matches the first unique bufftree ID of the first volume; if the volume ID of the data block matches the first unique bufftree ID of the first volume, determining that the data block is a correct data block; if the volume ID of the data block does not match the first unique bufftree ID of the first volume, determining whether the volume ID of the data block matches the second unique bufftree ID of the ancestor volume; if the volume ID of the data block match the second unique bufftree ID of the ancestor volume, determining that the data block is the correct data block; and if at least one of the data ID and the volume ID of the data block do not match, determining that the data block is an incorrect data block.