1. A method for replicating data to one or more online storage clouds comprising: providing a data replication cluster comprising at least a first host node and at least a first online storage cloud, wherein said first host node is connected to said first online storage cloud via a network and comprises a server, a cloud array application and a local cache and wherein said local cache comprises a buffer and a first storage volume and wherein said first storage volume comprises data cached in one or more buffer blocks of said local cache's buffer; requesting authorization to perform cache flush of the cached first storage volume data to said first online storage cloud; upon receiving approval of said authorization, encrypting said cached first storage volume data in each of said one or more buffer blocks with a data private key; assigning metadata comprising at least a unique identifier to each of said one or more buffer blocks; encrypting said metadata with a metadata private key; transmitting said one or more buffer blocks with the encrypted first storage volume data to said first online cloud storage; creating a sequence of updates of said metadata, encrypting said sequence with said metadata private key; and transmitting said sequence of metadata updates to said first online storage cloud.