Comcast Warning Letter about DNS (1 Viewer)

[Adam Sanchez]

Hey all,

I got a letter in the mail today from Comcast who is my internet and cable provider. I guess it has me a little worried. Nothing major really but I thought I would ask about it here.

Basically it's an email saying that I have to be set for Dynamic DNS or I could have service interruption. Now, I don't know if the letter is actually directed at me or if it's a sort of "reminder" that this is how they want it.

One of my computers is in fact set with a static IP and therefore a static DNS. It's been like this for a few months now. Of the 3 PC on my router, only one is set this way, the other 2 are set to dynamic. Are they able to tell that my computer is set to static? I had did to make downloading and port forwarding on my router simple since with automatic IP and DNS the ip address of my 3 computers can rotate.

Do I need to set this computer back to dynamic or they will catch it and interrupt my service? Or is there a way to configure my router so it looks the way they need it to be? Not trying to do anyhting malicious I just like my set up the way it is. The pc with the static is where I need alot of different ports opened which is alot easier with a static ip address.

Thank you for any input!

Adam

 

[Kimmo Jaskari]

I believe what they are saying is that your router port, the one that goes to the ISP, needs to be set to dynamic. I doubt very much that they care what your internal setup looks like; you only get the one IP address from them and they want to be able to issue that to your router dynamically using DHCP, a very normal setup for broadband accounts.

All your computers inside the router use one IP to contact the outside world, the IP number that your router has been issued by the ISP. The router converts from your internal IP range to the IP number used by the router, in other words, using NAT (Network Address Translation.)

So, as long as the router is set to use DHCP, you can keep your internal machines as they are - at least I assume that the letter you got was informational rather than a dire threat that you use DHCP or else!

 

[SethH]

If you open up the software section of your router (usually by typing the address of your router into a web browser) there is a place to enter addresses for DNS servers. In my router (a Belkin) you simply leave those fields black to set it to be dynamic. If your ISP gives you specific DNS addresses then you put them in there. It's pretty straight-forward, and you likely are already set to dynamic.

PS Don't confuse DNS and IP, two different things.

 

[Steve Berger]

What they are probably warning you about is the possibility that they may change the DNS of their server and at that time the static DNS PC will lose connectivity (to the internet) and you will need to reconfigure it to use the new DNS. If your router was set to a static DNS then then all of your PCs would lose internet connections. ISPs like dynamic because they can load balance easier.

OTOH, are you actually using a router and not just a switch? The IP addresses of your PCs should be quite similar (168.0.0.1 or 172.15.1.1) while the ISP would assign things like 221.24.22.24 .

 

[Adam Sanchez]

Hey all

Thanks for the replies. I checked my router this morning and it is (and always has been) set for automatic DCHP DNS so I imagine I am ok. I have always left everything automatic except that one computer so that's why the letter had concerned me. So I guess I am ok.

Thank you.

 

[ChristopherDAC]

Oddly enough, our DSL service uses a static IP address assigned by our ISP. I can only guess they have more server capacity than subscribers!

 

[Tekara]

I find that brick and mortor isps that buy their bandwidth from a major carrier prefer giving out static ips to their customers while the major carriers themselves prefer to give out dynamic ips.