Comment 2 for bug 2060172

I noticed that when the bug hits the pid of nginx is always the same (I monitored it using `for x in {1..10000}; do cat /var/snap/maas/current/http/nginx.pid; sleep 0.5; done`).

On the other side, when it works properly the pid changes.

Looking at http://nginx.org/en/docs/control.html , in our case it's enough to send a HUP signal to reload the configuration.

Still we can't really understand what happened, but it must be a nasty race with NGINX and pebble (like https://trac.nginx.org/nginx/ticket/424).