JohnnyComeLately's Journal: Bridging a Mac for Internet sharing, such as for XBOX in hotel's Wifi

I'm putting this here since I need a good place to reference this document in the future. Since I seem to be too busy to create and maintain my own domains, and squatters quickly jump on lapsed names, I'll put stuff here to live in infamy.

First, thanks to the comments on last journal. I now realize /. sends emails when I get replies to comments, but not journal entries. I'll need to check if that's a configuration error on my part. OK, for the technical details. I am on my way, possibly, to a war zone and like any good gamer geek, I have my XBOX360 with every type of interface cable (VGA, S-Video, Component, Composite, HDMI) and a few of my favorite games. While traveling, I got stuck in Belgium for NATO training and I lamented one day, "I wish I could get my XBOX online," to which a fellow geek said, "Don't you have a working Mac on WiFi in the hotel?" The light came on! Bridge the XBOX to the WiFi, via an Ethernet cord between the console and Mac. The reason I'm putting this together is after a couple of hiccups, I'd like a troubleshooting reference, along side an installation "how-to."

The beginning steps are very straightforward. Set the XBOX on a sturdy location, preferably in a corner because they're louder than a nearby freight train. Hook the Video cable up to the TV, power to power, etc. Remember, unlike nearly every other manufacturer in the world, M$ has a NON switching power supply. Hook a XBOX to European 220 volt plug, and you've got a really nice brick. Good luck finding replacement power supplies while on travel. Many hotels lock their TV's. In the case of Mercuer, I googled the TV's model number and utilized the unlock code. For Best Western, they use a Smart Card built in to the TV, so there is no way to unlock and your guest remote doesn't have the "configure" switch. At Ibis, I used the PC input.

For audio hookups alongside VGA or DVI, you have a few solutions you can try. The first I utilized was Line In for the Mac, which allowed me to use the Mac as a "pass thru" for audio. So the VGA hooked to the TV (or monitor which "borrowed" for awhile), and then the audio (RCA to mini-phono plug) went to the MacBookPro (now referenced as MBP), and then I hooked my headphones into the MBP's headphone port. Later, when I used the TV, the MBP wasn't really close by, so I bought Turtle Beach Gaming headset which is the wired version for $50. There is a wireless version for about double, or $99. So now the audio and video are good to go.

The XBOX has a configuration menu. From your XBOX dashboard, go to "My XBox". Scroll to the "System Settings," and then "Network Settings." I refuse to pay $99 for a Xbox only WiFi adapter, so mine's always set to "Wired," even at home where I use a WiFi bridge to connect the XBOX and a Blu-Ray player to my home WiFi, fooling both into thinking they're wired. From this menu, "Configure Network," will give you two parts to modify: IP and DNS. I'll come back to this in a moment as now we'll jump over to the MBP to get the settings needed to configure the XBOX.

Being old school, I love command lines. They're fast and easy, and if you know what you're doing, they're insanely more powerful. Once again, I digress. I like command lines, but there are graphical interfaces that are easy and will also get you this information. I will jump between them at times. First the GUI. Click on the Apple logo (top left corner) and "System Preferences." Click on Network, under "Internet & Wireless." Go to "Ethernet" and switch it to "Configure IPv4 Manually." I used 192.168.2.1, with subnet of 255.255.255.0. Do not put in a router. Go back to the Xbox, and bump the last octet by one and make sure it's the same network. So, Configure the XBOX to "Manual" IP with 192.168.2.2, subnet to 255.255.255.0 and then tell the XBOX the MBP is the gateway by putting 192.168.2.1 for "Gateway."

Now go back to "System Preferences", and look for "Sharing." Click on it and then look under "Service" for "Internet Sharing." Click on the box, and hit confirm/ok for the nag. You should now see "Internet Sharing: On", Share your connection from: Wi-Fi, To Computers using "Ethernet". If you're impatient or like to verify each step (for you ex-military types), a test will now show a good "Connection," but will fail for Internet. This is because the test for Internet does a DNS query of who is XBOXLIVE.COM and XEXDS.XBOXLIVE.COM, and at this point it won't likely find a DNS. I'm not sure why DNS requests fail on "Auto" and the MBP doesn't just pass the request along to it's own DNS, but it doesn't.

To find the MBP's DNS (assigned by the hotel's wifi router), click on "Wifi" on the MBP's Network Preference listing, and then "Advanced." You will see a tab, which reads, "DNS." Click it. On the left, you'll see two IP addresses. I think once I had nothing there, so the other way to see this is open "Terminal," and type in cat /etc/resolv.conf | grep nameserver and hit enter. These should be the same. Now on the XBOX, go to the DNS Settings and "Select" (A button). Select "Manual," and "Primary" server and enter the first IP address. Go back one, and do the "Secondary," with the second. Make sure when you finished to scroll down to "Done," as using "B" (Back) will back you out but NOT save your settings. Now, under Configure Network on your XBOX, you should see under "Basic Settings," the IP and DNS. To recap the XBOX's settings:
IP setting Manual
IP Address is your MBP + 1 (192.168.2.2)
Subnet 255.255.255.0
Gateway is your MBP IP (192.168.2.1)
DNS Setting Manual
Primary DNS xxx.xxx.xx.xx (from MBP)
Secondary DNS xxx.xxx.xx.xx (from MBP)

Back up and "Test XBOX Live Connection." The first link is the Ethernet cable between the XBOX360 and the MBP. If the test fails, then first go back to the MBP and check the Network (under System Preferences). The dot should be green and say "Connected" if the physical cable is good. If it's red, get another Cat5E or Cat6 cable. If green, click on it and verify your IP address and subnet. Go back to the XBOX, and make sure the MBP's IP is the gateway, the IP is on the same subnet and mask (e.g. 192.168.2.1 for the MBP and 192.168.2.2 for XBOX is good, if the XBOX is 192.168.3.1 it's bad. And for simplicity, just always use 255.255.255.0 for masking right now.). If it still fails, try returning to "Automatic", and reboot the MBP. I haven't had to reboot, but can't hurt. Now, go back to Manual, and retry the test.

The next step is a bit tricky. It does a DNS query. So your MBP can be on the Internet and this still fail. If the second step fails, then double check the DNS settings again. I used Wireshark at this point, and I could see the DNS query come in, but nothing go out. I opened up terminal, typed in nslookup and then entered EXACTLY what the console was looking up. At the > prompt I entered WWW.XBOX.COM and got back
Server: 195.238.2.21
Address: 195.238.2.21#53

Non-authoritative answer:
WWW.XBOX.COM canonical name =
www.gtm.XBOX.COM.
www.gtm.XBOX.COM canonical name =
www.xbox.com.edgesuite.net.
www.xbox.com.edgesuite.net canonical name =
a1123.dsw2.akamai.net.
Name: a1123.dsw2.akamai.net
Address: 194.78.100.155
Name: a1123.dsw2.akamai.net
Address: 194.78.100.154
However I noticed on Wireshark that on en1 (the Wifi) I didn't see the request go out, which I could see coming in en0. So I disabled internet sharing, and re-enabled it and the test passed. So despite Internet sharing working great for weeks, one day it just stopped "Sharing."

The last step is the most frustrating because you can't typically control it, or fix it. The last step first gets out to XBOX, but then connects via port 3074. So if you fail the last step, first check XBOX.com to see if others are complaining. I don't see a health page which tells you if they're down. If XBOX is up, then it's possible your hotel blocks port 3074, such as Best Western in Mons, Belgium does.

OK, few gems for posterity:
cat /etc/resolv.conf | grep nameserver (to get DNS)
ifconfig (to see configuration of network devices)
nslookup (to run DMS queries)

Thanks for reading and I'll edit this as I find errors or more tips, etc.