There were 2 rounds, first is initial round asking brief technical and behavioral questions. Second round is panel round of interviews which consists of 4 rounds each lasting to 45 mins.

This was with AWS, part of Amazon. The interviewers were from the San Francisco office. They switched the interviewer without notifying me, which I found unusual. The originally scheduled interviewer was in the interview, but lurked creepily without contributing anything. They told me that the original interviewer was there to "shadow", which was an obvious lie given his industry experience. The interviewer who did interview me had all the personality of a cardboard box, and asked only canned questions, including ones that were irrelevant. It was clear that neither of them had even glanced at my background. It's also clear that this wasn't a real interview--it was interview practice for an inexperienced interviewer. I expected better from AWS, but then again I'm not surprised either.