In this paper, the authors are to enhance the data storage security during disaster. So that IaaS (Infrastructure-as-a-Service) methodology will be implemented here. This is to provide prior security for the storage devices during malware attacks and also during disaster. In this paper, they have discussed about the data partitioning and data security during transfer of data. Related papers are taken survey and its advantage and disadvantages are discussed. Basically massive computation power and storage capacity of cloud computing systems allow scientists to deploy computation and data intensive applications without infrastructure investment, where large application data sets can be stored in the cloud.