@scottalanmiller said:
The first step, outside of the technical, would be to begin building a business case around the needs to understand the risk aversion financially. Once you have that you at least have solid numbers to talk to the business about rather than feelings.
This can be difficult but try to get a number on downtime. How much money is lost per minute, per hour, per day... something to that effect. This may not be a consistent number, the first five minutes of downtime might be worth zero but the first full day quite a lot. It varies by company. And you must take into account mitigation - like outages at night, time to send people to lunch, working from paper, etc.
Getting this gives us a real means of understanding the needs for availability.
I'm still trying to accumulate this info as I explained to them that they would be able to afford some downtime, and the cost for HA need to be justified against their lost, however they are more concerned with having the system up and working whenever needed, which so far appears to be all day, every day, at any time.