Multiple cascaded backup process

摘要

Provided are a method, system, and a computer program product handling a backup process. An instruction initiates a new backup from a source volume to a target volume using one of a plurality of backup processes. A cascade includes a cascade source volume and at least one cascade target volume, and a write to a storage location in one of the cascade volumes causes a copying of the storage location to be written in the cascade source volume to each of the cascade target volumes in the cascade according to a cascade order in which the at least one cascade target volume and the cascade source volume are linked in the cascade. The cascade is modified to include the target volume of the new backup in response to determining that there is an existing cascade, else a new cascade using the backup process of the new backup is created.

主权项

1. A method of handling a backup process comprising:
receiving an instruction initiating a new backup from a source volume to a target volume using a specified backup process type comprising one of a clone and a snapshot, wherein the clone comprises a point-in-time copy, and wherein the target volume holds a complete copy of data on the source volume; determining, from a computer readable medium maintained by a storage volume controller, whether there is an existing cascade of volumes using the specified backup process type including the source volume of the new backup, wherein a cascade includes a cascade source volume from which data is written to at least one cascade target volume using a cascade backup process type comprising one of the snapshot and clone backup process types; modifying the determined existing cascade using the specified backup process type to include the target volume of the new backup in response to determining the existence of the cascade using the specified backup process type; and creating a new cascade using the specified backup process type of the new backup including the source volume and the target volume of the new backup in response to determining that there is not the existing cascade using the specified backup process type, wherein a cascade extending from one source volume will only copy data to target volumes in the cascade using the cascade backup process type with which the target volume was created so that data from a clone backup process type is not copied to a target volume created using the snapshot backup process type and vice versa.