How can I setup Windows 2003 server using a Dynamic IP Address?

September 28, 2005 8:13 AM

I want to setup a Windows 2003 server using my dynamic IP address that I have from Comcast. How can I make this happen? I have a linksys Gateway (WCG200) that has the server and a few other computers connected to it. I am trying to setup a small server for my printing/web hosting/file sharing/remote access needs. I need to see how to setup my DNS & DHCP settings for this to happen. Also I have my own domain name which I would like to use. Can I use programs from companies like no-ip.com to setup my web site so if anyone types my registered domain it will find my site? Remember that I will be using a dynamic address. Or the last straw is to get a static IP address. Where can I do so(for the cheapest price)?
posted by nserrano to technology (7 comments total)

The gateway is the device that gets the public IP from comcast, not your windows server. Since the server is behind the gateway with other machines, it, and all the other machines, get private IP addresses, which can be static or dynamic, but that really isn't relevant to what you're trying to do, I think.

If you want to, for instance, run a web server on the Windows box, and have it accessible from the outside world, you'll need to go to the linksys gateway box and forward Port 80 from the outside world to the private IP address that your Windows machine gets from the linksys.

You can see what your Windows machine is getting by going to a command line (start > run > cmd) and typing ipconfig /all.

You can probably access the linksys control panel by visiting http://192.168.2.1, or something similar. See your linksys manual to be sure.

All of the above is applicable even if you had a static comcast IP. Since you have a dynamic IP, you'll want to use a service like dyndns, and you'll need a client that updates your account at dyndns running on a computer in your home.
posted by odinsdream at 8:28 AM on September 28, 2005

A lot of routers for home use have a configuration screen where you can set them up to use a dynamic DNS service. I use dyndns.org myself (since it's free and I have no cash for such things) and have no trouble connecting to my machine at home via a *.dyndns.org domain name. If your router doesn't have this capability, then the dynamic DNS service of your choice might be able to point you to third-party software that will automatically update the DNS entry for you.

The best option really would be to look at the FAQ lists for any DNS providers you're interested in; the details vary from provider to provider and will definitely vary based on your gateway. (I'd look up Linksys' own documentation myself, but they insist on using PDFs that open in popup windows, which brings everything to a halt.)
posted by staresbynight at 8:34 AM on September 28, 2005

ZoneEdit offers a free "dynamic DNS" service. I'd thought dyndns.org disappeared years ago, but apparently they're back from the dead and they also offer a free dynamic DNS service.

To use something like this you would go to your domain registrar, delegate SOA for your domain to ZoneEdit, and then run the dynamic DNS client on the gateway (or possibly on a system on the internal network, depending on how clever the client is at divining your DHCP-assigned address).

I don't know about your gateway, but I'm under the impression that most modern Linksys devices offer DDNS clients of some kind. I see it in the stock Linksys WRT54G menus, and that's a dirt cheap NAT gateway.

Once you've got DDNS up and running in some form, you'll have to look into setting up port forwards for the services you want to expose to the internet. I strongly, strongly caution against exposing Windows file and print services to the internet. Windows is insecure enough as it is when tended to by even an experienced system administrator, and it's a menace in the hands of someone who has to ask how to forward ports and delegate DNS.

You (and the world around you) will be much better off setting up some kind of VPN if you need to access such services remotely.
posted by majick at 8:43 AM on September 28, 2005

Yep, DynDNS is what you need. No-ip.org will work great for you. In fact, I've been using the free version at least 6 months with an always-on Yahoo DSL computer. No problems.

If the computer is always-on, no-ip.org (pretty sure this is the "free" domain offered by no-ip.com) offers a small background service that keeps your computer updated, which has worked fine for me. You will want to put this computer in the DMZ to make things easier, but you could also spend a bunch of time doing port redirection for the specific ports you want.

i don't have a big problem with exposing my file and print services to the internet when it's a personal, non-critical box, but I'm an asshole and magick has got a way better grasp of IT issues than i do, so you might want to listen to him.

huh. is ZoneEdit totally free? that's pretty cool.
posted by fishfucker at 10:24 AM on September 28, 2005

ZoneEdit is free up to a certain amount of DNS traffic per year. You'd have to run a pretty busy site to exceed this, since there's so much caching of DNS on the 'net.
posted by kindall at 11:01 AM on September 28, 2005

Speaking as another Comcast subscriber, I think that if you check your service agreement (TOS), you'll find that Comcast specifically prohibits dynamic DNS and running servers from residential accounts. As a practical matter, lots of folks do it anyway. But here's the rub:

Generally, it isn't worth an ISP's time to shut down everybody that is using some kind of small scale server on a home connection, as long as those servers are running within "normal" bandwidth allowances, and bothering no other subscribers. So generally, most ISPs turn a blind eye to this. But, if a box in their sub-net gets "owned" by a Trojan or worm, and starts creating problems, it is trivial to find it, and believe me, they will "TOS(S)" the subscriber in a heartbeat. Which is very inconvenient, particularly if your cable TV and IP phone services are running over the same system, and you don't have other available options to replace them.

So, if you are planning on forging ahead with this, you had better get to be as paranoid about security on your new Windows Web server as any other administrator. You need to setup the machine properly for only the services you intend to run (and for Windows 2003, that's not trivial), keep it patched, develop your Web site and other services with security in mind, monitor your logs, and test your security setup thoroughly and routinely. And even if you do it all "right," you can still have problems as new exploits for as-yet-unpublished Windows security holes are exploited.

You'd have the same responsibilities if you paid for a static IP on a business plan, but you'd be operating within the TOS for that kind of service, and not likely to lose your account connectivity for some unintentional incident. And you'd have access to business class tech support, that could help you analyze and resolve abuse issues if you are attacked.

But, IANAL and YMMV. Lotsa luck with this, and welcome to wonderful world of Windows system administration....
posted by paulsc at 11:15 AM on September 28, 2005

I've had Comcast cable internet for forever now. I've noticed that my ip never changes unless I power cycle the cable modem.

Otherwise, everything that odinsdream said is spot on. It's exactly what I do and has worked for years :)
posted by starscream at 1:55 PM on September 28, 2005