Handling Objections In Stroage Virtualization

Mark Teter, CTO of Advanced Systems Group, a Denver-based storage and server solution provider, on handling objections to storage thin provisioning:

EXTRA CAPACITY WILL BE THERE WHEN CUSTOMERS NEED IT: Some customers are concerned that they might over-commit the disk space to applications and then one of the applications runs out of capacity. When storage thin provisioning first came out, this was their primary concern. Their reaction is, why would I want to do that? You have to assure customers they can get extra capacity when they need it. And you have to tell them that thin provisioning will be the only way to manage storage in the future. For example, when replicating an Oracle database, you also replicate all the unused space. If storage capacity is only 20 percent utilized at the primary site, it will be 20 percent utilized at the replication site.

HELP CUSTOMERS WITH APPLICATION TESTING WHEN DEALING WITH WINDOWS NTFS: We tell customers that there is a case where a thin provisioning volume can swell in size because of the way Microsoft Windows deletes files. Microsoft's NT File System doesn't reuse released blocks of capacity from a deleted file when storing new data. Instead, it allocates new blocks, causing the volume to swell to its maximum size. For this, you have to test the applications. This is something we help clients with. If an application does this, it defeats the purpose of thin provisioning. We tell customers that this is an unusual situation.

DEMONSTRATE THE NEED TO BREAK OLD PURCHASING PRACTICES: We have had clients say that, because of the way budgets are handled on a yearly basis, they can only go to the bank once to make purchases, which they feel is not suitable for thin provisioning. We tell them they'd want thin provisioning anyway because of some of the side benefits. We also tell them they have to break the old habit of purchasing larger chunks of storage than they need. And thin provisioning gives the benefit of purchasing new disk technology at declining prices.

POSITION AS A VIABLE ALTERNATIVE TO MANAGING STORAGE IN THE DATA CENTER: At some point, you have to just point out the benefits. Thin provisioning is a feature that increases efficiency and management capabilities. But it's not a licensed software. It's built into the system. The answer is, don't use it for certain applications on certain volumes. You can turn it off for specific applications. That is, you just don't over-provision. You give the application a terabyte, and you know what? It's a terabyte.