Hello all, long time reader but first time poster so I'll start by thanking you all for the years of advice, fixes and good ideas I've been able to pick up here!
I've got a strange problem that's driving me mad and I wondered if any of the clever people out there might have an idea to point me in the right direction.
We've got a small number of devices (three at present, one Microsoft Surface Pro, two iPhones) that are able to connect to our network but not access the Internet and I can't figure out why. Here's the setup and steps I've taken, firstly with the Surface Pro as this was the first device to start misbehaving:
We have a fairly simple network, one VLAN, Virgin Internet and Smoothwall for proxy/filtering. The Surface can use local resources (shares, printers, etc.) with no problems either when working wirelessly or when docked but cannot browse the Internet, send/receive email or access any other offsite service when working on wireless - in its dock all works fine. The behaviour is common to multiple browsers - they all return a timeout message, Chrome being the only one that offers anything else as it at least shows 'Waiting for proxy tunnel' in its status bar for a few minutes before failing. It can resolve external addresses but pings fail, pings to our Smoothwall also time out. I've taken it home to test on my home wifi and it works fine. In both cases it is set to auto detect proxy settings but the behaviour is the same even if I manually specify our proxy address when onsite. This led me to think maybe something at the wifi end was blocking it since it works ok when connected to the dock and ethernet. We have two wireless networks in different buildings - Aruba in half the site and an old Extricomm system in the other half that's destined to be replaced with sitewide Aruba this year. These two systems don't talk to each other at all but the behaviour of the Surface is the same on both and neither appear to detect it as a Rogue AP or anything similar - the wireless performance is pretty great for anything on the local network so I don't think the problem is there. I then moved on to IP addressing and tried it with a few different addresses - DHCP, static and DHCP reserved - same results regardless. I tried reinstalling Windows in case something had gone screwy somewhere, both with the built in restore and with a fresh build from one of our images. Problem persists and even continues when I boot from an external OS on a USB drive - I've tried this with Ubuntu, Windows To Go and my trusty Hirens Boot USB - all the same behaviour. Smoothwall promise me that their box doesn't do any filtering based upon MAC, only IP and say that it's definitely nothing at their end so I feel like something between the device and the Smoothwall box is blocking web traffic. Having tried it in different areas of the site with different wifi systems the only other common factor sitting between the device and the Smoothwall box is our core switch (a HP 5406zl) but I can't see anything on there that indicates a problem. I was ready to think it was some extremely odd hardware issue with the individual device (though I couldn't see what since it works ok at home) when the two iPhones started behaving in what appears to be the same way.
I've got a horrible feeling I'm going to kick myself when I get to the bottom of this but at the moment I can't see the wood for the trees - can anyone suggest a direction to go in?
Thanks in advance for any help you can offer.