Someone posted a question about what should they try to learn for an interview coming soon, but the company was asking for information that they didn't know about. Their resume indicated experience in development, but the job description asked for HA skills.
What should you do?
First don't panic. I'm of the opinion that if a company calls you, they see some potential in your resume. There is a reason they called you, assuming that some recruiter didn't "spice up" your skills. In any case, it's too late to become an expert.
My advice is that if you have time, hours even, read up on the topics in Books Online or somewhere like SQLServerCentral.com and see if you can pick up the general idea and talk about the overall process or technology. Be perfectly honest that you're not an expert and don't get drawn into making things up, trying to answer questions you don't know, or trying to sound more educated than you are.
Instead you should talk about what you know and how well you can learn things. When I've been in an area that I'm not familiar with, I steer the interview back to a comfortable place by drawing a parallel in how quickly I've learned something or learned to solve a problem. That way I can build some confidence in the interviewer that I can do the work, or learn how, and also manage the interview to keep me looking in a positive light.
Never forget that someone's impressions of you when the interview is over will stick in their mind and it's what they'll tell someone else. Or write down. If they think you're a positive person, maybe underqualified, but they have a positive impression of you, that's what they'll remember.
So be honest, and talk about things that showcase your skills. And remember that job descriptions always ask for everything, and talk about way more than most positions really need.
Or will accept.