Patent Number: 8,793,223

Title: Online data consistency checking in a network storage system with optional committal of remedial changes

Abstract: A network storage server includes a tool for detecting and fixing errors while the network storage server remains online (available for servicing client requests), which includes enabling a user to approve or disapprove remedial changes before the changes are committed. The technique bypasses the usual consistency point process for new or modified data blocks representing potential remedial changes. At a consistency point, dirty data blocks representing the potential remedial changes are written to a change log file residing outside the volume. The modified data blocks are written in sequential order to logical blocks of the change log file. In response to a user input indicating that a potential change should be committed, the corresponding modified data blocks are read from the change log file in the order in which they were written to the change log file, and they are written to persistent storage in that order.

Inventors: Cho; Yong (Campbell, CA), Palem; Maya (Sunnyvale, CA), Sukumar; Vignesh (Santa Clara, CA), Edwards; John K. (Sunnyvale, CA), Grunwald; David (Santa Clara, CA), Kahn; Andy (San Francisco, CA)

Assignee: NetApp, Inc.

International Classification: G06F 17/30 (20060101)

Expiration Date: 7/29/12018