I've no idea what Amazon uses for Load Balancers, but I'm pretty sure that error message is the default error message served up by a Netscaler LB if no web services are available in the pool...
-andy > -----Original Message----- > From: Kevin Day [mailto:[EMAIL PROTECTED] > Sent: Friday, June 06, 2008 11:40 AM > To: Lasher, Donn > Cc: nanog@nanog.org > Subject: How not to make an error page (was: OT: www.Amazon.com down?) > > > On Jun 6, 2008, at 1:24 PM, Lasher, Donn wrote: > > > Checked, and doublechecked, not just me > > > > www.amazon.com returns: > > > > Http/1.1 Service Unavailable > > > > Anyone have a URL for a network/etc status page, or info on the > > outage? > > Been that way for a while this morning. > > > > -donn > > > > > > Even worse, the page they're displaying is actually a HTTP 200 > response code(OK/no error), with no "Don't cache this" header - which > means their error page is considered cacheable by some browsers/ > proxies. So, you may find users who tried to visit Amazon while they > were down are still seeing it down long after they fix it. > > Lesson to high profile websites: add these to your error pages so you > don't have people complaining you're still down long after you're > fixed. > > * Don't return a 200 response code. Use 500 or 503. Nothing from 2xx > or 4xx. > * Add a "Cache-control: no-cache, must-revalidate, max-age=0" header, > as well as an "Expires: 0" header for good measure. > * If your server is really borked and you can't add headers at all, > add '<META HTTP-EQUIV="Pragma" CONTENT="no-cache">' to the <head> > section. That's not as good, but helps at least on the browser end. > * If possible, add a timestamp to the page somewhere (even if it's in > an HTML comment) so you can troubleshoot with users still seeing the > error. > > -- Kevin >
