When it comes to getting an Internet Service Provider (ISP) for your business, one of the questions that comes up is "Do you need a static IP address?" In the eyes of the ISP, you have to have a static IP address if you plan on hosting your own applications, or even a VPN for remote access. They tell you this because they charge you for that block or even that single IP address. What that means is that your public IP address will always be the same. In most cases, like in your home, your public IP address is dynamic. The frequency of the change varies by ISP but usually ranges from 7-15 days. That time period is called your IP address lease. Sometimes, you will even get the same IP address when your lease is up. Again, that depends on a myriad of circumstances but for the sake of this quick tip, it changes every 7-15 days. If your IP address changes, and you host your application, the application will become unreachable because your Domain Name Server (DNS) will be pointing to your old IP address. So how do you go about hosting your applications with a dynamic address you ask? Here you go...
Navigate to a dynamic DNS host of your choosing. For this quick tip, we will use DynDNS.org. Open a free account and navigate to the "Your Hosts" section. Input the accont credentials that you created on the DynDNS.org website and the hostname you created Hostname.DynDNS.org. Now your router will update your IP address every time it changes and the CNAME record you created will always have the latest
Once that's done, navigate to your hosting companies DNS settings for your domain name. In this case, we will be suing the GoDaddy DNS administrator panel. In the zone file, create a new "CNAME" record and name it whatever you want. In this case, we will use VPN as the CNAME. In the hostname field, input the DynDNS hostname we created in step 2, Hostname.DynDNS.org.
Finally, you need to configure Dynamic DNS on either your router or a computer on your network. If you have a router that supports DDNS, like the WRT54G by Linksys, simply log into your router (if you don't know how to log into your router, consult the documentation that was included with your router). For this quick tip we will be using the referenced Linksys WRT54G router. Once logged in, navigate to the DDNS section of the web interface. From the drop down menu, select DynDNS.org as the hosting provider and input the account you created in step one. In the hostname field, input the Hostname.DynDNS.org that we created earlier. Once thats done, click on "Save Changes" and restart your router.
If you dont have a router that support Dynamic DNS, you can still use the DynDNS.org service by downloading the client HERE. Once downloaded, install the application and launch it. The first window that pops up is going to ask for your account credentials. Insert the credentials we created in step 1 once again.
Once you are logged in, your available hosts will be listed in the client window. Make sure you tick the box next to the Hostname.DynDNS.org host that we created earlier and click "Apply." The client will now update your IP whenever it detects a WAN IP change. The client will also automatically start whenever the computer is turned on. You want to keep this machine on at all times and because of that, it's best to make the client a server or other network service provider.
All done! You can now host your applications from a dynamic IP address. With the CNAME record we created, anytime you navigate to that address, it will automatically forward to the Hostname.DynDNS.org. Because we have that hostname setup on our DynDNS client, the IP address will always be right without us having to change any DNS records. As for website hosting, this example does not work as well because you have to create a subdomain in order to CNAME the record. You could forward all traffic going to YourDomain.com to Hostname.DynDNS.org but that would severely hurt you as far as traffic and Search Engine Optimization (SEO) goes.
As always, if you have any questions, comments, gripes, and/or complaints, please forward them to me directly at Frank@GandGNetworks.com. Be sure to check us out on Yelp by clicking HERE, Like us on Facebook by clicking HERE, and follow us on Twitter by clicking HERE.
Lead Network Engineer
G&G Network Design and Cabling, LLC