nanog mailing list archives
Re: How not to make an error page (was: OT: www.Amazon.com down?)
From: "Bjorn Townsend" <eriktown () gmail com>
Date: Fri, 6 Jun 2008 11:58:19 -0700
Good guess. AFAIK Amazon uses mostly Netscaler, with some homegrown stuff and a few F5 boxes. On Fri, Jun 6, 2008 at 11:49 AM, Andy Litzinger <Andy.Litzinger () theplatform com> wrote:
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:toasty () dragondata com] 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. -donnEven 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
-- Bjorn Townsend | eriktown () gmail com
Current thread:
- RE: www.Amazon.com down?, (continued)
- RE: www.Amazon.com down? Buhrmaster, Gary (Jun 06)
- Re: www.Amazon.com down? Wil Schultz (Jun 06)
- Re: www.Amazon.com down? IT Mailing List (Jun 06)
- Re: www.Amazon.com down? Jay R. Ashworth (Jun 06)
- Re: www.Amazon.com down? David Coulson (Jun 06)
- Re: www.Amazon.com down? Jay Hennigan (Jun 06)
- Re: www.Amazon.com down? Michele Neylon (Jun 06)
- Re: www.Amazon.com down? Jon Kibler (Jun 06)
- RE: www.Amazon.com down? Buhrmaster, Gary (Jun 06)
- RE: How not to make an error page (was: OT: www.Amazon.com down?) Andy Litzinger (Jun 06)
- Re: How not to make an error page (was: OT: www.Amazon.com down?) Bjorn Townsend (Jun 06)
- RE: How not to make an error page (was: OT: www.Amazon.com down?) Fred Reimer (Jun 06)
- Re: OT: www.Amazon.com down? Jay Hennigan (Jun 06)
- Re: OT: www.Amazon.com down? Marc Manthey (Jun 06)