Both have pluses and minuses depending once again on what you are attempting to accomplish. What is your RPO (recovery point objective) and RTO (recovery time objective) for your DR plan? Does it vary by application or is it uniform for the entire company? What type of DR plan are you implementing? One that works in the case of a major disaster, or one that lets you recover individual files easily and without system admin intervention?
Downsides for each of these solutions can be (not always) a lack of highly granular recovery that comes with continuous data protection (CDP). There are variations of these types of solutions that offer a CDP-like recovery. Server replication typically requires agents on every server and a "collector" that captures all of the replicated data locally or remotely. This can add to your server and admin costs. The SAN-based solution can be fabric based or array based. Fabric based can be appliance based, intelligent switch based, or combinations of the two. The fabric- or array-based solution tends to be simpler at the cost of less granularity for recovery than the server-based solution. Unfortunately, like all generalizations, this one is not always true.
My suggestion is to pick the solution that you are most comfortable implementing and operating, the one that best fits your DR plan objectives, and the one that best meets your budget constraints.
Dig Deeper on SAN technology and arrays
Related Q&A from Marc Staimer
Network File System and Common Internet File System/Server Message Block were designed to work with any operating system, but NFS remains dominant in... Continue Reading
Object storage has unique features, including erasure coding and multi-copy mirroring, which may make it better suited to data protection than more ... Continue Reading
Why would you attach NAND flash storage directly to the memory channel? Isn't RAM much faster than NAND? Marc Staimer discusses this and more in this... Continue Reading