Recovery-chain based retention for multi-tier data storage auto migration system

A computing system comprising:

• a media server;
• a network;
• and
• one or more client computers coupled to the media server via the network, each configured to generate data for one or more data images to be backed up in a multi-tier storage system;
• wherein the media server is configured to:
• identify first backup data that is qualified to migrate from a first tier to a second tier of the multi-tier storage system based on a time-based retention policy;
• responsive to determining the first backup data corresponds to a recovery chain stored on the first tier, wherein the recovery chain comprises at least one full backup data:
• prevent migration of the first backup data on the first tier,
• responsive to determining:
• the recovery chain is not expired;
• and
• the recovery chain includes at least a second backup data that is not qualified to migrate from the first tier to the second tier based on the time-based retention policy;
• and
• migrate the first backup data from the first tier to the second tier, responsive to determining the recovery chain is expired, wherein determining the recovery chain is expired comprises determining a new full backup operation has been performed and corresponding new full backup data is stored on the first tier.

A non-transitory computer-readable storage medium storing program instructions for defining a lifecycle policy for each of one or more data images, wherein the program instructions are executable by the processor to:

• identify first backup data that is qualified to migrate from a first tier to a second tier of a multi-tier storage system based on a time-based retention policy;
• responsive to determining the first backup data corresponds to a recovery chain stored on the first tier wherein the recovery chain comprises at least one full backup data:
• prevent migration of the first backup data on the first tier, responsive to determining:
• the recovery chain is not expired;
• and
• the recovery chain includes at least a second backup data that is not qualified to migrate from the first tier to the second tier based on the time-based retention policy;
• and
• migrate the first backup data from the first tier to the second tier, responsive to determining the recovery chain is expired, wherein determining the recovery chain is expired comprises determining a new full backup operation has been performed and corresponding new full backup data is stored on the first tier.