I was told I would get questions on computational science basics. The question was simple, string manipulation. It was so simple that I thought there was a trick. The interviewer however was blank. He was polite, but it felt like talking to the wall. After the coding he asked knowledge questions, and I don't even know how he thought I would know these considering my resume. If you apply to SRE position, don't study the huge book they give you, just prepare with coding exercises, especially strings.