sandys · January 7, 2014 15:15
diff --git a/gistfile1.txt b/gistfile1.txt
 As people mentioned this site is an exception to how to do things, in that PG actively does not care about search engine results. However, for the people who are interested, here's a few ways you can handle a situation like this.

 1. If you add the "max-stale" header to your content you can tell your CDN to hold on to things longer in the event of an outage. What happens is that the CDN will look at the cache time you set and check in as normal when that expires, but if it gets back no response or a 503 code (server maintenance status code- if you work with CDNs this is your friend!) it will continue serving the stale content for as long as you tell it.

 2. Lets say you're beyond that, or your site is too dynamic. Instead of setting up an error page that responds to everything, setup a redirect with the 302 status code (so crawlers and browsers know it's a temporary thing). Point that redirect at an error page and you're golden. The best part is these types of requests use minimal resources.

 What I do is keep a "maintenance" host up at all times that responds to a few domains. It responds to all requests with a redirect that points to an error page that issues the 503 maintenance code. Whenever there's an issue I just point things at that and stop caring while I deal with the problem. I've seen webservers go down for hours without people realizing anything was up, although with dynamic stuff everything is obviously limited. The other benefit to this system is that it makes planned maintenance a hell of a lot easier too.

 Oh, another thought- you can use a service like Dyn (their enterprise DNS) or Edgecast to do "failover dns". Basically, if their monitoring systems notice an issue they just change your DNS records for you to point at that maintenance domain. You can also trigger it manually for planned things.
	As people mentioned this site is an exception to how to do things, in that PG actively does not care about search engine results. However, for the people who are interested, here's a few ways you can handle a situation like this.

	1. If you add the "max-stale" header to your content you can tell your CDN to hold on to things longer in the event of an outage. What happens is that the CDN will look at the cache time you set and check in as normal when that expires, but if it gets back no response or a 503 code (server maintenance status code- if you work with CDNs this is your friend!) it will continue serving the stale content for as long as you tell it.

	2. Lets say you're beyond that, or your site is too dynamic. Instead of setting up an error page that responds to everything, setup a redirect with the 302 status code (so crawlers and browsers know it's a temporary thing). Point that redirect at an error page and you're golden. The best part is these types of requests use minimal resources.

	What I do is keep a "maintenance" host up at all times that responds to a few domains. It responds to all requests with a redirect that points to an error page that issues the 503 maintenance code. Whenever there's an issue I just point things at that and stop caring while I deal with the problem. I've seen webservers go down for hours without people realizing anything was up, although with dynamic stuff everything is obviously limited. The other benefit to this system is that it makes planned maintenance a hell of a lot easier too.

	Oh, another thought- you can use a service like Dyn (their enterprise DNS) or Edgecast to do "failover dns". Basically, if their monitoring systems notice an issue they just change your DNS records for you to point at that maintenance domain. You can also trigger it manually for planned things.