Network Storage Best Practices…

I am about to consolidate the plethora of data scattered throughout my network onto one NAS device. I am a firm believer in not putting all my eggs in one basket so I want to create a second NAS device that “mirrors” the other. This way in case of emergency I can simply failover to the second. I have done lots of reading about DFS and the like. I don’t think DFS is what I should be looking into. With my situation I was looking for some direction from other people. What would you guys do?

TIA.