| 摘要 |
The invention provides for a method and apparatus for the rapid generation of a snapshot copy of the data stored in a RAID storage subsystem (100). In addition to the user's configured RAID logical units (110), the present invention provides for the definition within a RAID controller (102) of a logical RAID level-one device (104) having an operational half (106) comprising the user's defined logical unit(s) and having a non-operational mirror component (108). The user access data is stored on the RAID subsystem by direct access to the user's defined logical unit and when a user directs a snapshot copy request to the operational half (106) and user defined logical units (110), the RAID controller (102) responds by temporarily configuring available storage capacity (e.g. spare disk drives) in the RAID subsystem to perform the function of the non-operational mirror component (108) of the logical RAID level-one device (104). Restoring operation of the non-operational mirror component (108) further causes the RAID controller (102) to rebuild the content of the restored mirror component by copying the content of the user's configured device(s) to the temporary replacement mirror component (124). Following completion of the rebuild operation, the logical RAID level-one device (104) is restored to the status of having a non-operational mirror component (108). The data copied to the temporarily reconfigured available storage capacity is then returned to the user requesting the snapshot data for further processing as, for example, backup. <IMAGE> |
