Tuesday, June 9, 2009

Apple Mac OS X Airport/Ethernet Internet Connection Sharing for DirecTV On Demand

If you have an Apple computer with an active wireless connection, and would like to use the Ethernet port on the Mac to use DirecTV's On Demand service, read on.


A few months ago we signed up with DirecTV and had a HD-DVR installed. If you've done the same, then you know you need an Internet connection to take advantage of their On Demand service. Well, the satellite box is nowhere near my router, and I put off purchasing a wireless network adapter for the DVR thinking there might be another solution not requiring an additional cash outlay.


A few weeks later I took advantage of a sale at HP's web site, and purchased and installed a Media Vault. It acts as a central repository for data, and includes a server for streaming music to compatible devices.


Like anyone else, I wanted to take full advantage of the capabilities of the music server. So I connected my Mac mini to the TV and AV receiver, and by utilizing the Mac's wireless Airport adapter and Front Row - Apple's media center software - I was soon playing digital tunes streamed from my Media Vault on my stereo component system. Cool!


So there I was with the family one evening watching some forgetful program. My eyes not glued to the TV, wandering down to my lonesome little Mac mini, dozing in the corner. And it hit me like a train.


The Mac has an Ethernet port I'm not using, and the HD-DVR has too - I mean two - Ethernet ports. If I can share the Ethernet port on the Mac and connect the DVR to it, we can get On Demand at our command.


Well I did just that and it didn't work. The On Demand connection works right up to trying to connect to the Internet, and then it craps out. ¿What was I doing wrong?


I searched the Internet high and low. I went to the Apple and DirecTV support site and forums and couldn't find the solution. I tried every search string I could think of until I finally entered "internet connection sharing mac," and what I found was a host of Xbox 360 users wanting to basically do the same thing, but with their game machines, and succeeding.


Hats off to the gamers. Like DirecTV's satellite boxes, IP addresses and subnet masks can be manually entered into Xbox 360s, and the gamers figured out that the Xbox gateway IP address has to be that of the Mac's Ethernet port. Duh! I should have known that.


Here's how to get DirecTV On Demand working by physically connecting it to your Mac that is connected wirelessly to the Internet. Oh!, and by the way, please read this entire post before trying this on your own, and remember - you are attempting this at your own risk. I cannot be held liable for any changes to your equipment that results in any type of loss. If you don't feel comfortable attempting this modification, leave it to an expert to try.


After establishing a wireless Internet connection with your Mac, go to System Preferences/Sharing Internet tab. Share your connection from: Airport To computers using: Built-in Ethernet. Please note: if you don't see Built-In Ethernet on the list you will have to first turn it on in System Preferences/Network.


Next, get physical; attach one end of a standard Cat-5 cable to the Mac's Ethernet port and the other end to Port 1 on the back of the DVR.


Now use the DirecTV remote and follow the instructions for setting up On-Demand, and select Advanced Setup to enter the values manually.


Here are the values to enter:


IP Address

192.168.2.2

Subnet mask

255.255.255.0

Gateway

192.168.2.1

DNS Server

Your router's IP address


What you are doing - essentially - is creating a virtual subnet consisting of two devices, the external Ethernet port on your Mac, and the satellite box. So disregard the fact that you may be using an entirely different set of IP addresses for your home network. The only IP address you enter on the satellite box that will resemble your home network is that of the DNS server. It must match the IP address of your router, or your Internet connection will fail. If you don't know what the IP address of your router is, look at the Airport TCP/IP configuration in System Preferences/Network.


Remember that the gateway address you enter on the DVR is the external address of the Ethernet port on your Mac. The IP address on the satellite box is one of your own choosing, but it has to be one that is not masked out by the subnet mask. ¿Not sure what I'm talking about? Just add one to the fourth octet - as in the example above - and you'll be okay.


¿How do I know the IP address of your Ethernet port? Well I don't, but it's an educated guess based on research.


If you want to find out for yourself just open up Terminal.app in the Applications/Utilities folder and type in ifconfig en0. Somewhere in there you will see inet 192.168.2.1. That is the gateway address. If I'm wrong, then please use the correct address returned by the ifconfig en0 command, and add '1' to the fourth octet to get the IP address of your cable box.


Here is what my configuration looks like.


Cable box

Mac Airport

Mac Ethernet

IP Address Configuration

Static (Manual)

DHCP

DHCP

IP Address

192.168.2.2

192.168.1.11

169.254.x.x

Subnet Mask

255.255.255.0

255.255.255.0

255.255.0.0

Gateway

192.168.2.1

192.168.1.254

DNS Server

192.168.1.254

192.168.1.254


The external IP address of the Mac's Ethernet port is 192.168.2.1. This is the port and address that provides the gateway for the satellite box. The DNS server address is that of the router.


Ignore the Mac Ethernet port 169.254.xx.xxx IP address, and the yellow light that appears before the Ethernet port on the Network Status page in System Preferences/Network. The Mac is assigning itself a private IP address, and can be disregarded for our purpose.


All we need the Ethernet port for is Internet connection sharing, and if you just got it to work you are awesome. Pour yourself a drink, and download some Mad Men reruns.
© Copyright 2009, by Edmund Jimenez, All rights reserved.