Recovery of file system data in file servers mirrored file system volumes

An apparatus comprising:

• a plurality of mirrored file system volumes, each having at least one snapshot including an entire consistent file system, each said snapshot having a consistency point value indicating a sequence in which each said snapshot was generated;
• a first comparison element capable of being coupled to a plurality of said consistency point values and capable of determining a most up-to-date mirrored file system volume of the plurality of mirrored file system volumes based on the consistency point values;
• and
• a second comparison element, responsive to an output of said first comparison element, said second comparison element being capable of being coupled (a) to a first snapshot associated with said most up-to-date mirrored file system volume and (b) to a second snapshot associated with a second said volume, said second comparison element being capable of providing a selection of file blocks that differ between said second volume and said most up-to-date mirrored file system volume.

An apparatus to maintain a plurality of mirrored file system volumes, the apparatus comprising:

• a first element capable of creating at least one snapshot for each mirrored file system volume of the plurality of mirrored file system volumes and including a consistency point value in said at least one snapshot indicating a sequence in which said at least one snapshot was generated;
• a second element capable of examining the snapshots of the plurality of mirrored file system volumes for consistency point values;
• and
• a third element capable of determining a most up-to-date said file system volume based on the consistency point values.