Google Linux, Networking & Scripting interview questions

The question that separates people who have debugged a hung rollout from people who have read about one. The interesting half is not the signal, it is PID 1.

A staple of every networking round, and the follow-up is always about TLS termination. Knowing which layer sees what decides most of the answer.

The oldest question in systems interviewing and still the best, because it is unbounded: the interviewer stops you when you run out of depth, and where you stop is the score.

The question that reveals whether someone knows what load average actually counts on Linux. It is not a CPU metric, and that single fact resolves the whole thing.

The classic ephemeral port exhaustion question. Most candidates know the phrase TIME_WAIT; far fewer know which side accumulates it and why the popular fix is dangerous.

The scripting round in disguise. The constraint is the question: it exists to see whether you stream or whether you load, and everything else is about whether the script is safe to run twice.

The two-syscall duet behind every process on the box. The follow-ups live in what survives the transition, and candidates who skip that fail the next question.

Everything top, htop and your APM agent display is derived from procfs anyway. Knowing the raw files turns any bare SSH session into a monitoring console.

Multiplexing removes application-level queuing and hands the problem to TCP. Here is where the blocking really lives, the loss math behind it, and the four levers that help.

Loss-based versus model-based congestion avoidance decides whether your WAN transfers fill the pipe or die on the first stray drop. Here is the operator's decision, not the RFC summary.

Anycast turns BGP convergence into your failover mechanism. Sessions stick to the site they landed on, monitoring must go per-site, and a route you cannot withdraw cleanly is worse than DNS.

Two different resources produce the same errno, and the second one is invisible unless you know to look. One command distinguishes them.

A beginner question with a senior follow-up hiding in it. Once you know a hard link is a second name for an inode, log rotation and backup behaviour both stop being mysterious.

Everyone recites the four letters. The scoring answer walks each packet across the wire and knows the places the exchange silently dies.

Interviewers use this to sort memorised trivia from people who have chased a slow lookup. Three roles, one bit, and the caching rules most candidates repeat incorrectly.

A routine cloud operation with three layers that can quietly disagree. The strong answer is an ordered procedure you could run during business hours, without a reboot.

The answer is yes, and then the real question starts. Asymmetric routing and silent drops punish anyone who treats the routing tables as one flat list.