Our Website hosts have (as a result of an office move) moved my work website to a new server “with improved bandwidth and IP routability”. For a while after the move has taken place, here at work we get a “This site is under maintanance” message showing, although we are assured that the site is up and running. Then we remember that we need to update the internal DNS servers with the new IP number, since the domain names are the same - :smack: all round, 'cause this happened last time we moved server. So we apologise to Webhost for accusing them of messing up and call IT Consultant, who dutifully changes the IP reference in the domain controllers DNS Forward Lookup.
Now we get a new message when trying to view our site - “No web site is configured at this address.” :dubious: “That’s what you shold get if you type the IP number into a browser” says Webhost, “You need to put that IP address into your internal DNS system and then use http://www.ourdomainname to see the site.” Pinging the new IP number also gets no response - “Well, it wouldn’t, the new server is behind a firewall” says Webhost, “Your IT guys need to sort out your end, everyone else can see the site”. I give up and go home for the night - test the site from home, and there it is, all sparkly and new. A new day - I call IT Consultant who says “I’ve changed the IP number as you told me, Webhosts must have changed their security set up - I can’t help you”
grimpixie sighs :(… It’s going to be a long day… and Manager is conveniently off sick so Staff are all asking grimpixie when the site is going to be visible…
And so to the General Question… - From the info above, does anyone have any thoughts about a way forward? Or any questions that a semi-tech like me can ask either of the two consultants, to elicit a helpful response?
Is the bandwidth to your office supplied by the same host? If you are, then you may be on the same LAN as the website as far as they’re concerned. That is, your external router might have an IP address on their LAN and point to their gateway to reach the Internet. Depending on how their LAN and gateway are set up, you might not be able to address other machines on their LAN using Internet addresses.
For example, on one of our production server locations, we have several machines acting as web servers and data processors. These machines are on a LAN by themselves and have a firewall between them and the Internet. If these machines need to talk to each other using HTTP, you have to use the local address (e.g. 192.168.1.x) rather than the Internet-routable IP or domain name.
Of course, if your bandwidth is supplied by someone else, then this is irrelevant.
It sounds as though something on your network is stripping the HTTP “Host” header out of your requests before they get sent to the server hosting your website. Why it would do this, I don’t know. It seems an unlikely behaviour.
Without the host header in the HTTP request it’s equivalent to trying to directly browse the IP address of the site - which your service provider is clearly aware of since they recognise the distinction between browsing to the hostname URL and the numeric address.
Try adding a line in your host file ("<windows folder>/system32/drivers/etc/hosts" if you’re on windows) that maps the “www.ourdomainname.com” to the new IP address. If this fixes the problem then it’s your internal DNS that needs fixing. Try “ipconfig /displaydns | more” from the command line and see if an incorrect IP address is listed for the domain. If so, then “ipconfig /flushdns” may resolve the problem.
yes, Armilla’s got good advice with the host file. In fact, if the internal DNS entries were misconfigured, this can be a temporary work-around until they fix it right.
Another thing to test is to check what IP address the DNS name actually maps to. Pinging it should tell you.
Unfortunately, Armilla’s suggetion of changing the host file has resulted in no change at all, so it seems that the stripping of the header is taking place at the other end of the line…
In addition, we have discovered that another domain that we own, which should point to the same IP as the main domain (and is), also gives us the “No web site is configured at this address” message. This domain is different from our network’s domain and should therefore not be affected by anything to do with the internal DNS server!! Webhosts reluctanly admit that this is very odd and they will have a think about it… :rolleyes:
These last seem to strongly imply it’s at the hosters end. The only two possibilities I can come up with are pretty obvious: either the individual web site isn’t accessable (say the permissions were misset, or no site existed), or the hosters machine is misconfigured. In fact, even if the individual web site wasn’t accessible, I would think you’d get a different message.
The message you’re getting is exclusive to IIS (I believe). I can’t offer much in the way of advice on where a misconfiguration may lie, but that’s really at the hoster’s end anyway.
Armilla wrote
I agree with that last part. In fact, I expect it’s highly unlikely, to the point where I’d rule it out. Many (most?) web sites out there use this technique, and it would be shocking if any network equipment would intentionally modify packets in such a way to break this standard internet setup. Also, unless I’m terribly mistaken, this happens up above TCP, so modifying would require maintaining state across packets, which makes it more troublesome in a few ways.
MannyL - the browser seems to find the site just fine. Everyone outside of our network can find the site just great, it’s only us here in the building that are having the problem…
Armilla - as far as I know, there is no proxy involved, certainly we don’t have one here…
We (Network Consultant and I) had logged into a remote server and were looking at the site from there when we thought to ping it - lo and behold, it came up with a different IP number to the one we had been given by Webhosts. “Worth a shot” we thought, plugged it into the DNS server and bingo!
The next morning, Webhosts send an email saying “… it occured to me that your website has an SSL cert section which means it’s also bound to IP Number that we found above (your own reserved IP address for the SSL server). Maybe that’s what you need to tell your “techies” needs plumbing into your oddly setup DNS system.”
Well, I don’t know what to think, but at least we can see the site for now…
Unfortunately so… Thanks