Ah yes that old chestnut… SAN versus DAS – switch to DAS and save a load of money. It’s obvious right? Well I’m not sure. This is still a hot topic but the bottom line is that Exchange 2007 now gives us a lot more options about which storage we choose to support our Exchange data. ..and for many deployments it does now make sense to consider more cost effective storage since we can achieve similar levels of resilience at an often significantly reduced cost. This is going to be important in getting your project off the ground. This article on the subject is certainly worth reading; Storage Design for Exchange Server 2007 - How Microsoft IT Exceeds High-Availability Targets with Large Mailboxes at Low Costs Based on New Storage Designs.
The key to the storage argument is generally two-fold. Firstly you need to demonstrate that your chosen storage solution is the right one to meet the performance and availability requirements that you have of it but perhaps more crucially, if you are introducing something new to your organisation, it’s important to make sure that the solution is supportable from within your IT department. The last thing you need is for your manager to think that your cost cutting measures are going to lead to future supportability or resilience headaches.
Once your team are clear in which direction you want to go, and you have support from management, then you need to be able to show cost saving. The new ‘Exchange Server 2007 Mailbox Server Storage Cost Calculator’ is the place to start here. “…the Exchange 2007 Mailbox Storage Cost Calculator is designed to help you determine a portion of the mailbox server cost, namely the disk cost (purchase price and lifecycle power and cooling costs).” Like with server costs the information that is going to sway the decision is demonstrating cost saving in terms of data centre space, power consumption and supportability.