Honestly, you should talk to the pros. I would call a couple of storage vendors, give them the basic outline of what you want to do, and let them tell you how they would do it. You can even get more formal and issue a Request for Information (RFI) or even a Request for Quote (RFQ). If you're a biggish company, your purchasing people probably have an SOP and standard forms for how to issue an RFI/RFQ. For the big boy storage vendors, half a petabyte is commonplace. The bigger question may very well be what this is going to look like at a software level. Managing the data might be a bigger challenge than storing it. Is this going to be organized in some sort of big data solution like Hadoop? Is it just a whole bunch of files and a people are going to write R or SAS jobs to query against it? Sometimes the tool set that you want to use will drive your choices in how to build the infrastructure under it.