You could google "HA", click in the Wikipedia link that shows all the things "HA" may refer to, and deduct that the most logical thing in the list, given the context, would be this link: https://en.wikipedia.org/wiki/High_availability.
The statement about having poor deductive logic skills was the more insulting part of the post (compared to ignorance of an initialism, which I think you are correct in thinking is insignificant).