Patent attributes
An incremental backup is made of a source volume on a production host to on premise secondary storage. The incremental backup includes a bitmap specifying locations of blocks that have changed since a last backup of the source volume, and data of the changed blocks. First checksums are calculated from data of the changed blocks. The incremental backup, including the changed blocks and the bitmap, are moved to cloud storage. The changed blocks are merged, at the cloud storage, with the last backup of the source volume to generate a synthetic full backup of the source volume. The bitmap is consulted to identify locations of the changed blocks. Second checksums are calculated from data written to the locations on the synthetic full backup. The first and second checksums are compared. If the first and second checksums do not match, an indication is generated that the synthetic full backup is corrupt.
