How to block iPhone OS DNS on my network

Question

How to block iPhone OS DNS on my network

Using an iPod Touch 2g, OS 2.2.1.

I'm trying to make all devices on my network use OpenDNS only. So, with my hardware firewall I've blocked all outgoing requests on port 53, expect for OpenDNS servers. Works great on all my computers (Windows & Linux, wireless & wired): they can only resolve a hostname if they are using OpenDNS' servers. Port 53 is blocked for every host, except OpenDNS.

However, the touch still can use whatever DNS server it wants, and still work. Is there something that I'm missing here? How does iPhone OS (maybe OS X too?) resolve names? Doesn't it use port 53 also?

Thanks!

iPod Touch 2g, Windows XP, 2.2.1

Posted on Apr 15, 2009 10:44 AM

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Answer 1

luvlabs

Level 4

3,620 points

Apr 15, 2009 4:25 PM in response to christopherstamper

Welcome to Apple Discussions

I not sure most of us care which port is used by DNS, but i think I can help you out.

From what I understand, you have a hardware firewall on your network. Devices on your network, get their DNS information from the router. So, if you set your router DNS to OpenDNS, that will be the only DNS used by your network.

The same is true for the touch. Since your network supplies it with its IP address and Subnet Mask, it also supplies it with the default DNS from your router. As long as you are connected to your network, you will use OpenDNS.

Where you can't control using OpenDNS is if your touch is connected to another network. You have to use the DNS client of that network. The same is true of any device used to connect remotely.

The iPhone software for WiFi is exactly the same as the touch. OS X works like any other OS when it comes to networking.

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Answer 2

Apr 15, 2009 7:23 PM in response to christopherstamper

I see what your saying, luvlabs. And I have already done that. The problem is, users can still use whatever DNS server they want.

I talked to the company that made my hardware firewall, and there's actually something wrong with it, not the iPhone OS. So Im going to mark this as resolved, since it's a firewall issue.

Thanks!

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