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April 26, 2004

An Appeal To Geekdom
Posted by Patrick at 08:10 PM *

Patrick here, at Making Light’s helm. Cripes, all the controls are in the wrong place, and what is this…substance? drying? fermenting? sprouting tiny flowers? I tell you, other people’s workspaces are always full of surprises. Anyway.

So the problem is, swapping the old cable modem for a new one didn’t fix the constant service interruptions, and in fact right now we’re getting no broadband service at all. The earliest a Time Warner Cable tech can come to our house is Wednesday, so it’s dialup until then.

Here’s the thing. (Tech neep coming; normal people, bail now.) We have two perfectly normal G3s running OS X Panther. We can get a nice solid dialup connection via the built-in modem on Patrick’s iBook. Allegedly, sharing that dialup connection to Teresa’s blue-and-white G3 via Ethernet is simplicity itself—click “Start” in the Internet sharing dialog and stand back, more or less.

Except that we can’t get it to work to save our lives. We’ve googled up several dozen web pages that rhapsodize over this procedure’s ease. We’ve tried every combination of Ethernet cables, hubs, routers, DHCP, DHCP With Manual Addressing, deleting the “ethernet” configuration and building a new one—everything, on both computers. God knows we have enough old hardware kicking around here. And we know the Ethernet cables and the connections on the computers themselves are good. But nada. The dialup connection works great on the iBook, and simply will not share out to Teresa’s blue-and-white G3.

I can’t help but think there’s something stunningly obvious that we’re missing. Like, everybody knows you have to dip the Ethernet cable in peanut butter. How could we have missed the peanut butter? Anyway, if you’re a OS X-savvy networking person who thinks it would be a better universe if Teresa could get online on her own computer, please drop me an email at at your convenience. We could exchange email, AIM, or I could even phone. Advice and counsel needed, asap…

Comments on An Appeal To Geekdom:
#1 ::: d'Herblay ::: (view all by) ::: April 26, 2004, 08:53 PM:

Have you tried turning everything off, waiting a minute, and then turning everything back on? In my experience, this solves most Mac connectivity issues.

#2 ::: Dori ::: (view all by) ::: April 26, 2004, 09:04 PM:

Can I get a little more info about what does happen? Nothing whatsoever, or ? Can the two machines see each other if hooked up via Ethernet (outside of being able to hit the outside world)?

#3 ::: Lenny Bailes ::: (view all by) ::: April 26, 2004, 09:24 PM:

I know not from Macs; but there are a few simple elements to connection sharing:

1) Are there firewall settings turned on on your machine or Teresa's that might be interfering? Also, is the cable modem connection on her machine temporarily disabled?

2) Is the NIC on Teresa's machine set to receive an IP address from yours instead of using a static address? (This would be some variant of an "Enable DHCP" option in her TCP/IP settings.) If the machine is set for DHCP, does it, indeed, receive an IP address? If not, that's the first thing to troubleshoot -- cable connectivity and so on.

3) If Teresa's machine does receive an IP address from yours, can she ping the static IP address of your network card? (Your machine, at this point, should have one static address for it's ethernet card and one variable IP address from the dialup modem.) If no, troubleshoot that.

4) If Teresa's machine can successfully ping the static NIC in your machine; make sure that that same IP address is set up to be the TCP/IP gateway on her machine. If the gateway is set up and can be pinged, but no Internet addresses respond (for instance,, can she ping or connect to a URL by its IP address, instead? (For instance, is

Assuming that the problem is not a firewall setting on your machine or hers:

If her machine responds to an Internet address by IP, then the problem may be the DNS server

If her machine won't respond to an Internet address by name or IP, but it will ping and connect to your static IP, then the problem is something to do with the IP translation (viz NAT, IP Masquerading, etc.) on your machine. This would be some problem in the Mac "Share Internet Connection settings" to probe.

#4 ::: Patrick Nielsen Hayden ::: (view all by) ::: April 26, 2004, 09:37 PM:

Yes, I've power-cycled everything; yes, the two machines can "see" one another in the OS X Finder's "network" view; no, there's no special firewall software involved.

#5 ::: Lenny Bailes ::: (view all by) ::: April 26, 2004, 09:45 PM:

Then there's the question of Teresa's machine grabbing the right DNS server. (Particularly, if it will respond to Yahoo by IP address but not by name.)

If there's anything equivalent to "binding order" make sure that the TCP/IP connection between Teresa's machine and yours is set to be the primary connection on her machine. On your machine, my instinct is that the dialup connection should be primary -- and the cable modem connection should be disabled on both.

Otherwise, Jordin or Erik will probably be along in a little while

#6 ::: Alan ::: (view all by) ::: April 26, 2004, 09:47 PM:

I'm not sure if this matters anymore (someone told me once that it doesn't, but he was of questionable character), but is the ethernet cable a crossover cable? For a direct connection between two PCs (no router), I think a crossover cable is prescribed. Otherwise, I have nothing, as I'm unfamiliar with the ins and outs of OS X networking.

#7 ::: Jordin Kare ::: (view all by) ::: April 26, 2004, 10:07 PM:

Jordin or Erik will probably be along in a little while

Thanks, Lenny, for the implied compliment, but I am only marginally clueful about these things. ("The definition of a computer guru is 'someone who knows one more trick than you do.'")

If the machines can see each other in network view, it's not a hardware (cable) problem. (as a double check, you can turn on file sharing on one machine and make sure they can trade files).

The one thing I can suggest is that when I've had no luck with a dialup connection, it's sometimes because I failed to enter a valid DNS server IP address in the TCP/IP tab of the Network system preferences. Doesn't seem to matter for other types of connection. Patrick, do both machines have the correct DNS server entered? If so, I'm out of clues...

#8 ::: David Dyer-Bennet ::: (view all by) ::: April 26, 2004, 10:08 PM:

Crossover vs. normal cable *mostly* matters; some switches/hubs have some or all ports "auto-sensing", but most do not. Patrick did say he was on top of the cable issues, so I doubt that's the problem.

If the cable modem was being the DHCP server (which it normally is, I believe), there may now be a problem in that there's no DHCP server in the network, so some or all systems may not be getting an IP address (or may be using some unexpected default).

#9 ::: Patrick Nielsen Hayden ::: (view all by) ::: April 26, 2004, 10:10 PM:

We're using a hub, so the crossover cable issue is moot. Besides, as I said, the machines were seeing one another's files, even when the internet connection was refusing to share.

Note the past tense, because in fact, thanks to the husband of Digital Medievalist, the problem is solved. And indeed one of Lenny's suggestions was correct--I had the iBook's firewall turned on. Duh.

As I said to Mr. Digitalmedievalist, "One generally prefers the answer to be one's own dumb mistake. Those kinds of problems are easy to fix."

#10 ::: Brooks Moses ::: (view all by) ::: April 26, 2004, 10:13 PM:

(Sorry for incoherence; typing quickly, need to leave momentarily)

One way of checking to see if DNS is the problem is to ping a numeric IP address from the "non-dialup" computer.

Other thing to check is what the "non-dialup" computer has set up for the IP address to use as a gateway.

The "dialup" computer should have two IP addresses; one given by the dialup connection, one on the internal network consisting of your ethernet crossover cable. The IP address that it has on the internal network should be what the other computer has set for a gateway.

#11 ::: William Donohue ::: (view all by) ::: April 26, 2004, 10:15 PM:

Panther's adaptability may be screwing things up - in attempting to provide seamless connectivity no matter where you are, it has a tendency to flip through all permutations of the available hook-ups. Often all that is needed is to limit Panther's choices:

1 - On the iBook, look at System Preferences/Sharing/Internet. 'Share your connection from' should be the internal modem. 'To computers using' should only have Built-In Ethernet checked.

2 - On the iBook, System Preferences/Network/Network Port Configurations should have only the internal modem and the built-in ethernet checked. On the G3's, only the built-in ethernet should be checked.

3 - On the G3's, System Preferences/Network/Built-In Ethernet, click on the TCP/IP tab. Make sure all the fields are blank (the one option here is to try the 'Search Domains' field as either blank or with your dial-up service providers base url - AOL users, for instance, might put here).

4 - Press the Apply Now button on the lower right corner of TCP/IP preference pane now.

5 - On the G3's, System Preferences/Network/Network status will now show connection status and IP address. If this shows no connection, now would be the time to shut all the machines down, then bring up the iBook and its dial-up connection, then power up the G3's and see if you get a connection.

6 - If all else fails, fix yourself a big drinky-drink and call Cory Doctorow or Joey DeVilla for their m4d netwerking skillz.

Good Luck

#12 ::: Lenny Bailes ::: (view all by) ::: April 26, 2004, 10:16 PM:

Also see if this link is any help. Under the "Share Your Connection from" dialog on the server, choose "modem" or "built-in modem" to computers using "built-in Ethernet" (or Airport, if it's a wireless link between you and Teresa). Under the Network settings on the client, configure IPv4 to "Show" the ethernet card, not the Firewire port shown in the picture. And if there's a way to disable the Cable Modem connection, try that.

Apologies, if this is obvious and you've already been there.

#13 ::: Patrick Nielsen Hayden ::: (view all by) ::: April 26, 2004, 10:39 PM:

As I said, the problem is solved; indeed, Lenny's very first guess was the correct one.

However, practically the moment our home networking problems were solved, our hosting service evidently had a five- or ten-minute downtime. Jeez. What next. No, don't answer that.

#14 ::: Avram ::: (view all by) ::: April 26, 2004, 10:41 PM:

Didja try sacrificing a chicken?

#15 ::: Teresa Nielsen Hayden ::: (view all by) ::: April 26, 2004, 10:48 PM:

Avram, we did in fact cook a chicken this evening. I'm glad to think it may have helped.

#16 ::: Andy Perrin ::: (view all by) ::: April 26, 2004, 10:50 PM:

Peanut butter.

#17 ::: Brooks Moses ::: (view all by) ::: April 27, 2004, 12:08 AM:

Wouldn't the peanut butter be mostly for Food Transfer Protocol (ftp) connections, though?

#18 ::: Bill Humphries ::: (view all by) ::: April 27, 2004, 12:21 AM:

No, but if you feed some peanut butter to a dog it'll provide hours of amusement while you're waiting for the connection to come back up.

#19 ::: Giacomo Lacava ::: (view all by) ::: April 27, 2004, 05:42 AM:

I work in an helpdesk for a major software company (supporting a non-english speaking country, that's why I'm not in India yet). Lots of times, what does put us analysts "on the wrong path" is an uncorrect communication from the user. It's normal, we know that and we understand users != geeks, but please, when the troubleshooter tells you "do this, check that" just do it :) we won't ever ask you to wear your pants on the head and run on the streets shouting "we love you Woz!" just for fun... oh, wait... ;)

#20 ::: Yahmdallah ::: (view all by) ::: April 27, 2004, 11:04 PM:

I think some wingnut group is going through blogs and making sure that anyone not genuflecting to Bush has login troubles. We had to switch ISPs to get back on the web recently. And even our new service has halted twice, causing a dispatch to the field each time. Last time, it cleared up by itself when the tech was at our house testing stuff. Odd, huh?

Remember, we are dealing with "Nixon, the Sequel" (or "Son of Nixon" for my age group).

#21 ::: betsy ::: (view all by) ::: April 28, 2004, 01:38 AM:

when i am especially irritated with the one i live with, i tell him that i am going to put peanut butter on him while he's asleep. the dogs looooove peanut butter.

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