Data consistency between virtual machines

Data consistency between a primary virtual machine and a recovery virtual machine may employ a resync engine to detect differences in data blocks stored on both virtual machines. For example, the resync engine may calculate a signature (e.g., hash value) for a primary data block and a corresponding signature for a recovery data block, and compare the signature and the corresponding signature to identify a difference between the primary data block and the recovery data block. In some instances, by identifying a difference between the primary data block and the recovery data block, a data block (e.g., primary data block or recovery data block) may be identified to be transferred from a virtual machine to another virtual machine.