I have a site where the standard Drupal maintenance page is the simplest way to communicate short periods of down time with. our users.
The problem is that when Drupal emits a maintenance page, it attaches a status of 503. AFAICT, this is the same error status a lot of nginx configurations use to indicate that your PHP-FPM instances have passed away and ceased to pine for the fyords :-)
What's best practice here? Right now, we're in a configuration where a 503 causes our elastic load balancers to effectively shut down the site (not my idea). Which means once we go into maint mode, the site goes down entirely.
Due to the way we deploy, using an nginx maint page (detected with a -f arg, for example) is not a good option. Is there a reasonable way to configure nginx so we can distinguish a maint page from a dead FPM?