It looks like `nginx -s quit` returns immediately rather than blocking until nginx has finished gracefully shutting down. As a result, just running `nginx -s quit` in the preStop hook won't work very well for high load and/or long running requests; nginx will get a TERM signal (and do a hard shutdown) immediately after `nginx -s quit` returns.
(I was getting connection errors while terminating pods, and adding a sleep-until-done to the preStop hook seemed to make them go away.)
Ben Kuhn
Qiming