iSCSI vs FC – Is It Still A One Sided Debate?

I went on a trip this past weekend with one of my good buddies who happens to be a very knowledgeable Network Engineer. We were discussing some on the technologies his company was implementing in their environment, and got on the topic of their new VDI rollout and how a decision was made to use iSCSI vs FC SAN for their shared storage for their ESX backend.

Back when I got started on ESX, it seemed like all the architects preached FC SAN storage if it were at all possible. Speed, reliability and  scalability were just a few of the many arguments for it. Sure it was costly, but it was the best option out there.

But these days, technology is growing at a rapid pace. You can spend your whole day browsing tech sites and blogs reading about new technologies and products being released by multiple vendors. All these new technologies create more choices, and create different approaches to designs that used to be one-sided debates.

Back to my buddy’s company. Their VDI team actually decided to go with iSCSI over FC SAN for their storage. Their reasoning had a lot to do with what we deal with everyday. First and foremost was cost. Lets face it, FC SAN is one of the most expensive solutions to shared storage. Fiber switches, HBAs, SAN devices; the cost starts to add up, and very quickly. NAS and iSCSI have always been cheaper solutions, but in the past have been less superior options than FC SAN. But even that is changing.

These days, network companies are coming out with faster and faster switches. With switches commonly available in up to 10gbps speeds, FC SAN is no longer the fastest game in town. Before, Fiber was the way to get a reliable and speedy connections between your host and your storage. Now with copper moving into new speeds, that is no longer the case. Security and speed as well as scalability are now available through the deployments of dedicated iSCSI networks, creating new design and deployment options for companies.

As a colleague pointed out to me today, an advantage of using iSCSI is that since it is network traffic over copper, it makes it easier to troubleshoot and exam the traffic during any issues, via sniffers, etc. FC makes things a lot more difficult to track down issues on the fiber network between the host, the switches and the SAN devices, since you cannot just break into the fiber to catch the packets.

All and all, I think iSCSI deployments will become a lot more popular and you will see a lot of companies lean that way versus FC SAN storage. This isn’t to say FC is now the wrong way to go, because it’s not. It’s a tried and proven solution for shared storage. I just think that during these tighter economical times, that companies will explore cheaper yet reliable solutions and I think iSCSI will be one implemented a lot.

What are your thoughts on things? Are you using FC or iSCSI? Which do you prefer and why?