I have quite a strange situation and hope you can help me figure it out.
I am running a student server that is hosted by my school. We have our own public IP address on the net, and I was told once that we are on the DMZ of their network. Our server runs Ubuntu 8.10 LTS with the standard LAMP packages.
My problem is that all requests addressed to those other servers the school owns and hosts systematically time out from our server. For instance; with wget, it resolves, tries to connect, and times out. Same thing with fopen() on php, or when I try to browse a website through a proxy configured on the server. However, all those resources (the one I try to retrieve with wget for example) work perfectly fine when accessed from home, which would rule out a firewall system on their side. And I also ruled out a firewall on our side since wget google.com works perfectly fine.
I know we've been experiencing some DNS issues, but resolving seems to work. So what could be the problem in your opinion? My guess is it has something to do with the network, but that's beyond my comprehension. I'd like to try everything I can on my side before bothering the sysadmins on the other side...
Thanks very much for any help!
- dig and nslookup work fine
- using ip instead of domain name makes no difference
- I have no visibility over the other servers, but since they are fully accessible over the net, I should be able to do so as well, no? Furthermore, this problems seems new, as it used to work a year ago... Can I force access through a different route?
- Just to give you the heads up, after sending a mail to the sysadmins, it took them approximately 10mins to "do something" and inform me that their firewall rules had been wrongly implemented when migrating last summer. Everything works fine now.