Initial interview began with 15 minute screening by HR. Once you pass that they will invite you in for the 1st/2nd rounds of face to face interviews consisting of 2-3 hours each. They ask you tech questions from fundamentals of DNS to Email MTA methodology and process. Then they grill on a the basic of networking and OS stuff. They have been known to interview many candidates for one position. But the HR is very cordial, organized, and keep up up to date of their decision process.
