On Sat, Jul 02, 2011 at 10:23:44AM +0100, Wayne Stallwood wrote:
On 01/07/11 23:01, Chris G wrote:
Quite, but how do I diagnose it?
Do you run DNS on your Lan or just forward DNS requests through your router(s). If you have local DNS then I suggest you set that up to point zbmc.eu to the local address of your web server rather than the internet facing one.
Yes, I have local DNS (another computer on the home LAN running dnsmasq). However there is a reason for setting it up so that zbmc.eu requests go 'out and back' as it were, it means I can do much more realistic checks that I have set things up right so that the outside world can see zbmc.eu.
Most of the time I access the local servers with short 'LAN' names, e.g. zbmc.eu is chris on the local LAN so http://chris/ works fine.
The reason this is happening is that quite possibly the gateway for whichever connection zbmc.eu resolves to cannot route to itself. So if your request happens to go out on that gateway (assuming it is truly random and I am still not sure how you have that set up) then it is unable to form the circular route to connect back to your webserver through port forwarding or DMZ or however you have that set up.
It is fairly random, the router supposedly chooses whichever route is less loaded and as they're both pretty similar speeds and there's more than one of us here using them then, although there's a fair chance one will get chosen first fairly frequently the other will get used by the next request.
When your request goes out via the other ADSL connection it will work just like it does for anyone else looking at those pages (they load reliably for me)
I guess that's a possible reason, I can check easily enough by forcing all requests for zbmc.eu (84.45.228.40) to go out via the other ADSL connection, the router can do this quite easily. I have, for instance, already forced all HTTPS requests to go on one ADSL connection only as otherwise many secure servers complain because they check for an unchanged IP.