Monitoring other people's sites (Was: Website for returns "HTTP/1.1 500 Internal Server Error")

Jason Hellenthal jhellenthal at
Tue Mar 20 11:29:14 CDT 2012

On Tue, Mar 20, 2012 at 03:54:13PM +0100, Jeroen Massar wrote:
> On 2012-03-20 15:40 , Vinny_Abello at wrote:
> > FYI - it's also the main IPv4 site, not just IPv6... although I'm
> > unsure if it's the same issue.
> > 
> > I was monitoring availability as a point of reference for my network
> > and started receiving 500 errors recently as well that tripped up the
> > monitoring system, even though the page comes up in any browser I
> > try.
> > 
> > GET / HTTP/1.1 User-Agent: Mozilla/4.0 (compatible; MSIE 4.01;
> > Windows NT)
> For everybody who is "monitoring" other people's websites, please please
> please, monitor something static like /robots.txt as that can be
> statically served and is kinda appropriate as it is intended for robots.
> Oh and of course do set the User-Agent to something logical and to be
> super nice include a contact address so that people who do check their
> logs once in a while for fishy things they at least know what is
> happening there and that it is not a process run afoul or something.
> Of course, asking before doing tends to be a good idea too.
> The IPv6 Internet already consists way too much out of monitoring by
> pulling pages and doing pings...
> Fortunately that should heavily change in a few months.
> Greets,
>  Jeroen
>  (who noticed a certain s....h company performing latency checks against
> one of his sites, which was no problem, but the fact that they where
> causing almost more hits/traffic/load than normal clients was a bit on
> the much side, them pulling robots.txt solved their problem to be able
> to check if their IPv6 worked fine and the load issue on the server side
> was gone too as nginx happily serves little robots.txt's at great speed
> from cache ;)
>  And for the few folks putting nagios's on other people's sites, they
> obviously do not understand that even if the alarm goes off that
> something is broken that they cannot fix it anyway, thus why bother...

I agree! leave the monitoring for those that are hired to do so. Using
someone elses server to verify that your ipv6 connectivity works should
just strictly get your traffic dropped or null-routed with an alert sent
to your provider.

ping6 your provider... wget -6 your provider but beyond that you, most
likely cannot fix it...

;s =;

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