As Linux establishes itself as a mainstream operating system, and open source tools and applications prove their enterprise readiness, a growing number of organizations are talking publicly about their open source deployments and direction. Recently, Mok Choe, CTO at Union Bank in Monterrey Park, Calif., spoke with Network World Senior Editor Jennifer Mears about the financial institution’s decision to scrap proprietary Unix systems for commodity servers running Red Hat Linux. Here is an edited transcript of their conversation:

Give me some background on your move to Linux and open source.

We were faced with having to do an upgrade of our Web infrastructure last year, which gave us an opportunity to really look at our architectural direction. We decided to head in the direction of horizontal scaling using commodity hardware and open source tools. There are multiple drivers behind this thing. Cost is clearly one of them. First and foremost always is the reliability and performance. The second thing is we wanted to be able to scale much easier than we do today. Since we run on big boxes, at some point to scale you have to buy another big box. Instead of that, we wanted to be able to rapidly manage capacity by adding or subtracting commodity hardware.

Had you been using any open source software previously?

On a smaller scale, a Linux deployment did exist, but in very small, departmental solutions.

How did you decide that it was time to look at a broader deployment of Linux and open source?

That was part of the overall architectural direction that we decided upon for our Web applications. From the enterprise perspective, it was a big decision. Going with the commodity hardware was a big decision. Going with open source was a big decision.

So you determined that open source had reached a point that you felt comfortable bringing it into larger production environments?

Yes, we have a number of people who have had experience with Linux, including myself in my previous job, so we were rather comfortable going with that decision. We did make sure that we are meeting all the compliance requirements, so both internal and external regulatory bodies were consulted.

How did you go about that?

Since we are going the open source route, everything must be open, so to speak. All the documentation that’s required has been satisfied, and we have an internal arm auditing our use of open source tools.

You were running AIX servers, WebSphere and Oracle databases. Was there reluctance among the bank’s management on the business side to move away from proprietary best-of-breed?

I wouldn’t call it reluctance. But we did do a lot of education upfront. We started really small and proved the maturity of the technology, as well as covering all the processes from the enterprise project management perspective, as well as from the risk management perspective.

A year or two ago I would think the move to open source would have been a harder sell.

Yes, but now, even in a highly regulated space like banking, there are a number of solutions that take advantage of open source tools. As a matter of fact, let’s say you go to a contract on IBM’s WebSphere, you will actually find open source components in there. That’s a fact.

Do you know how much you’ll save once you make the transition?

Yes, we did a complete multiyear ROI analysis, but I don’t want to give specific numbers. Any savings has to do with our overall approach, so we didn’t separate Linux over AIX, for example, [and say that] is giving us this much savings. It was our existing architectural approach vs. what we’re building.

Previously, your architecture was centered on big SMP [symmetric multi-processing] systems?

Yes, we use systems running on RISC-based processors. But we decided to put together a plan and we did an ROI analysis across all of the infrastructure, as well as the applications, in our Web space — from the server to the network to security to load balancing and to the applications themselves. What we’re doing now is beginning to move in the direction of our new architectural road map. We are currently tackling the server infrastructure, the network infrastructure and the security infrastructure. Linux is part of that initiative.