nginx will not start on boot, but starts fine manually. The logs say something like
nginx: [emerg] host not found in upstream "{some hostname}" in /etc/nginx/conf.d/some_site.conf
nginx: configuration file /etc/nginx/nginx.conf test failed
Failed to start A high performance web server and a reverse proxy server.
nginx.service: Unit entered failed state.
nginx.service: Failed with result 'exit-code'.
It seems that on bootup dns is not ready yet and nginx is trying to lookup a hostname that I have in as a reverse proxy.