Explain the conntrack state machine. Which timers retire a connection, and why does the table fill with no leak?

Table full is the symptom everyone knows. The interview answer lives one layer down: per-state timers, the five-day ESTABLISHED default, and what conntrack -S says about hash pressure.

Grounded in researched DevOps, SRE and platform engineering interview loops, written to a senior-engineer editorial bar, and never padded to hit a word count.