Meta Production Engineer interview questions

Got a call for 4 rounds of Interview 1st normal telephonic, 2nd coding challenge, 3rd will be my systems round and I am crossing finger for Menlo Park. In the first telephonic interview asked basic questions on networking and linux to check wether I have strong knowledge in both of those to proceed farther, then there were 2 coding challenges which I believe I did good and currently am looking forward for third round.

4 total interviews, Phone, coding, systems, onsite. I made it through the first phone interview and the coding interview, the systems stuff was really what got me, they asked a lot of hard questions and were very serious about making sure their hires knew linux inside and out.