Security+ vs CISSP

Someone asked me to compare Security+ vs CISSP, particularly the difficulty. I’m glad to oblige. I have both certifications.

Let’s start by looking at a couple of hypothetical questions. Don’t expect to see either of these on the test; I’m making them up as I go. But don’t be surprised if you see something similar.

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Speed up Windows XP, Vista, and 7

I was looking for something else entirely when I found this PC World article: Speed Up Windows by Stripping it Down.

That’s a familiar concept. It includes several tips that apply to XP, Vista, and 7.
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Open-source licenses, the CISSP, and the real world

You may have a question about open-source licenses on your CISSP exam. I don’t remember the specifics and wouldn’t be able to repeat them anyway, but I had a question on my exam where knowing the differences was helpful in finding the right answer.

And I had to deal with an issue this past week involving open-source technologies where the licenses made a big difference.

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Buffer overflows explained

Buffer overflows are a common topic on a Security+ exam. The textbook explanation of them is confusing, perhaps even wrong. I’ve never seen buffer overflows explained well.

So I’m going to give a simplified example and explanation of a buffer overflow, similar to the one I gave to the instructor, and then to the class.

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Microsoft buys and then discontinues Linux/Unix antivirus products

First GeCAD, now Sybari.

Microsoft has been buying smaller anti-virus firms and discontinuing their Linux and Unix product lines.

Trust, schmust. When your god is Big Business, that means Big Business can do no wrong, so when you’re the U.S. government, you let companies like Microsoft do whatever they want. The problem is that Unix antivirus products are extremely useful, especially in Microsoft shops. Unix viruses are rare, and the heterogenous nature of Unix–never knowing much about the underlying hardware, binary incompatibilities between various dialects even when running on the same hardware, and never knowing for certain which libraries are installed–creates a hostile environment for viruses anyway.

So what good is a Unix server that detects viruses that can’t survive in Unix anyway? It makes a great buffer between the hostile world and the soft and chewy Windows boxes inside corporate firewalls, that’s what.

I love to put Unix boxes in between the world and mail servers that may be running Windows. Just set it up to relay mail to your Exchange or Domino server, but have it scan the mail first. Better yet, have it running on weird hardware. A slightly elderly Macintosh or Alpha or Sun box works great. Since the Intel x86 instruction set is the most common, most buffer overflows use it. While non-x86 processors aren’t immune to buffer overflows, an overflow using x86 instructions will appear to be gibberish and it won’t run. It’s like telling me a lie in Japanese. You won’t fool me with the lie, because I don’t speak Japanese, so I won’t understand a word you’re saying.

Fortunately, there are still antivirus products for Unix and Linux out there. And once Microsoft establishes its antivirus product, it will be more difficult–I hope–for it to simply continue buying antivirus firms and discontinue their products, since now they would be buying off competitors, rather than just attempting to acquire technology that they don’t have the ability to develop internally.

And even if they do buy and discontinue everything, there’s always ClamAV.

Help! I do tech support for everyone I know! (Version 1.1)

Here’s an interesting dilemma: How do you avoid becoming the primary technical support contact for all of your friends and family?

(If this sounds vaguely familiar, yes, this is a revised version of something I wrote a year and a half ago.)This was a question Richard “Rich Job” Jobity asked two Christmases ago. I thought it was an unbelievably good question. I had to think about the answer for a while. That label fit me for a very long time. Sometime within the last couple of years it stopped, but I never knew exactly why. He made me think about it, and I found I’d done some interesting things on a subconscious level.

There was a time when I didn’t mind. I was 16 and still learning, I had some disposable time on my hands, and, frankly, I enjoyed the attention. You can learn a lot by fixing other people’s computers. It can also be a good way to meet lots of interesting people. And I used at least one of those friends as a reference to get my first three computer-related jobs. But over time, my desire changed.

I think a good first step is to identify exactly why it is you don’t want to be the primary technical support contact for all your friends and family.

In my case, I spend 40 hours a week setting up and fixing computers. And while I definitely spend some time off the clock thinking about computers, I also definitely want to spend some time off the clock thinking about something other than computers.

I have a life. I have a house to take care of, I have meetings to go to, and I have a social life. Not only that, I have bills to pay and errands to run, and physical needs to tend to as well, like cooking dinner and sleeping. And people get really annoyed with me for some reason if I don’t ever wash my clothes.

I’ve been in that situation. Once I had a friend calling me literally every night for a week with some new computer problem and keeping me on the phone for several hours a night while we tried to sort them out. A couple of years before that, someone in Washington was running a computer company and using me as his primary (unpaid) technical support, often taking an hour or two of my day, and getting upset if more than about 12 hours passed without me responding.

I think it’s perfectly understandable for any reasonable person to not like situations like this. So here are my tips for someone who wants to head off that kind of a problem.

Have realistic expectations on all sides. So the first step is to make sure your friends and your family understand that you have responsibilities in life other than making sure their computers work. You’ll do your best to help them, but it’s unrealistic to expect you to drop everything for a computer problem the same way you would drop everything for a death in the family.

Limit your availability. Don’t help someone with a computer problem while you’re in the middle of dinner. You’ll be able to concentrate better without your stomach growling and you won’t harbor resentment about your dinner getting cold. Have him or her step away from the computer and go for a walk and call back in half an hour. The time away from the computer will clear his or her mind and help him or her better answer your questions. Don’t waver on this; five-minute problems have ways of becoming hour-long problems.

Here’s a variant of that. I had a friend having problems with a Dell. She called Dell. She got tired of waiting on hold. “I know, I’ll call Dave,” she said. “Dave’s easier to get ahold of than this.”

She may have tried to call me, but last week I was everywhere but home, it seemed. She didn’t leave a message, so I didn’t know she’d called. The moral of the story: Don’t be easier to get ahold of than Dell. Or whoever it was that built the computer or wrote the software.

What if I’d been home? It depends. If I’d been home and playing Railroad Tycoon, I’d be under more obligation to help a friend in need than I would be if I were home but my girlfriend was over and we were in the middle of dinner or a movie. The key is to remember your other obligations and don’t compromise on them.

Sometimes that means not answering the phone. In this day and age when 50% of the population will answer their cellphone even if they’re sitting on the toilet, this is heresy. I usually make a reasonable effort to answer the phone. But if I’m in the middle of something, I won’t. At least one time when I made no effort to answer the phone when my girlfriend was over, she took it as one of the biggest compliments she ever got. (That relationship didn’t last, so maybe I should have answered the phone, but hey, at the time I didn’t feel like it.)

Whoever it was didn’t leave a message. If it’d been important, either they would have left a message or they would have called me back. (Maybe it was the friend who’d thought of using me as a substitute for Dell tech support. Who knows.)

Don’t do a company’s work for them. If someone’s having a problem with a Dell, or having a problem dialing in to the Internet, I stay away from the problem. If a Dell is having hardware problems, the user will have to call Dell eventually anyway, and the tech will have procedures to follow, and there’s no room in those procedures for a third-party diagnosis. Even if that third party is a friend’s cousin’s neighbor who supposedly wrote a computer book for O’Reilly three years ago. (For all the technician knows, it was a book about Emacs, and you can know Emacs yet know a whole lot of nothing about computer hardware, especially Dell hardware. But more likely he’ll just think the person’s lying.) For the record, when I call Dell or Gateway or HP, I jump through all the same stupid hoops. Even though I’ve written a computer book and I’ve been building and fixing computers my entire adult life.

And if someone can’t dial into an ISP, well, I may very well know more about computers than the guy at the ISP who’s going to pick up the phone. I may or may not be more intelligent and and more pleasant and more articulate than he is. But the fact is, I can only speculate about whatever problems the ISP may be having. And seeing as I don’t use modems anymore and haven’t for years, I’m not exactly in a good position to troubleshoot the things. Someone who does tech support for an ISP does it every day. He’s going to do a better job than me, even if he’s not as smart as I am.

Know your limits. A year ago, a friend was having problems with OS X. She asked if I’d look at it. I politely turned her down. There are ideal circumstances under which to try to solve a problem, but the moment you’re seeing the OS for the first time isn’t it. She called Apple and eventually they got it worked out. It’s a year later now. Her computer works fine, we’re still on speaking terms, and I still haven’t ever seen OS X.

Around the same time, another friend toasted her hard drive. I took on that challenge, because it was PC hardware and she was running an operating system I’d written a book about. It took me a while to solve the problem, but I solved it. It was a growth opportunity for me, and she’s happy.

And this is related to the next point: If you’re not certain about something, say so. It’s much better to say, “This is what I would do, but I’m really not sure it’s the best thing to do” than it is to give some bad advice and pretend that it’s gospel. Get your ego out of the way. There’s no need to try to look good all the time. No matter what you do, you’ll be wrong sometime. And one of the easiest ways to be wrong is to run your mouth when you don’t know what you’re talking about.

Limit your responsibility. If your uncle has a six-year-old PC running Windows 95 and ran out and bought a USB-only printer because it was on sale at Kmart and now he’s having problems getting it running and he never asked you about any of this, how much responsibility should you be willing to shoulder to get that printer running?

I’m inclined to say very little. It’s one thing to give some bad advice. It’s another to be dragged into a bad decision. If the only good way to get the peripheral running is to buy Windows XP and wipe the hard drive and install it clean, don’t let that be your problem.

Don’t allow yourself to be dragged into giving support for free software downloaded off the ‘Net, supercheap peripherals bought from who-knows-where, or anything else you can’t control.

You can take this to an extreme if you want: Partition the hard drive, move My Documents over to the second partition, and then create an image of the operating system and applications (installed on the first partition, of course). Any time you install something new, create a new image. When your friend or relative runs into trouble, have him or her re-image the computer. He or she can reinstall Kazaa or whatever notorious app probably caused the problem if desired, but you can disclaim responsibility for it.

Which brings me to:

Disclaim all responsibility for poor computer habits. Gatermann and I have a friend whose brother repeatedly does everything I’d do if I wanted to set out to mess up someone’s computer. He downloads and installs every gimmicky piece of free-with-strings-attached software he can find, turning his computer into a bevy of spyware. He runs around on Kazaa and other file-sharing networks, acquiring a busload of who-knows-what. He opens every e-mail attachment anybody sends to him, amassing a large collection of viruses. He probably does things I’ve never thought of.

Gatermann installed antivirus software on the computer, and we’ve both run Ad-Aware on it (if I recall, one time I ran it I found 284 instances of spyware). Both of us have rebuilt the system from scratch numerous times. The kid never learns. Why should he? Whatever he does, one of Tim’s friends will come over and fix it. (I guarantee it won’t be me though. I got sick of doing it.)

Some good rules to make people follow if they expect help from you:
1. Run antivirus software and keep it current. This is a non-negotiable if you’re running Windows.
2. Stay off P2P networks entirely. Their clients install spyware, and you know about the MP3 buffer overflow vulnerability in WinXP, don’t you? Buy the record and make your own MP3s. Can’t afford $17 CDs? Buy them used on Half.com then.
3. Never open an unexpected e-mail attachment. Even from your best friend. It’s trivially easy to make e-mail look like it came from someone else. If someone who knows both of you got a virus, you can get virus-infected e-mail that looks like it’s from that friend.
4. If you don’t need it, don’t install it. Most free Windows software comes with strings attached in the form of spyware, these days. If you don’t want to pay for software, run Linux.
5. If you must violate rule 4, run Ad-Aware religiously.

Don’t take responsibility when someone asks your advice and then refuses to follow it. That unpaid gig doing tech support for a computer company in Washington ended when he had a computer that wouldn’t boot. He sent me the relevant files. I told him how to fix the problem. The next day he complained it didn’t help, and sent me the files again. It was obvious from looking at the files that he didn’t do what I told him to do. I called him on it. He got defensive. He caught me on a bad day and I really didn’t want to hear it. The next day he sent me a long list of questions. I answered the first two or three, then said, “Sorry, I’m out of time.”

I never heard from him again. But at that point it was just as well. Why help someone who doesn’t respect you enough to follow your advice?

A less extreme example was when an ex-girlfriend’s younger brother refused to give up Kazaa. Every time I fixed the computer, he reinstalled Kazaa and one problem or another came back. Finally I told him, her, and their parents that I’d fixed the problems, but they were going to keep coming back as long as he used Kazaa. Ultimately they decided that free music was more important than a stable computer and staying within the law, but that was their decision.

Have other interests besides computers. My former high school computer science teacher took me aside a few years ago and asked me if it wouldn’t be great if someday people asked me as many questions about God as they were asking me then about computers.

I have relatives who know I’m into Genealogy, and they know that I’ve traced one branch of my family through William the Conqueror and all the way back to before the time of Christ. But some of them don’t know I fix computers for a living.

Some nights when I come home from work, I don’t even turn a computer on. I go straight to the basement, plug in my transformers, and watch a Lionel train run around in circles. I might stay down there all night except for when the phone rings (there are no phone outlets in my basement) or for dinner. Ronald Reagan used to do that. He said it helped him relax and take his mind off things. My dad did too. It works. And no, there’s no computer hooked up to it and there won’t be. This is where I go to escape from computers.

So I don’t find I have the problem anymore where people only want to talk to me about computers. Balance is important. Don’t let your computer knowledge keep you from pursuing your other interests.

Charge money. I don’t charge my family members, but with very few exceptions, I don’t do free technical support. I do make sure I give friends, acquaintances, and neighbors a good deal for their money. But if helping them is going to keep me from mowing my lawn, or if it’s going to force me to cancel plans with my girlfriend, then I need to be compensated enough to be able to pay someone else to mow my lawn, or to take my girlfriend out for a nice dinner that more than makes up for the cancellation.

It’s all about balance. So what if your entire block has the most stable computers in the world, if your grass is three feet tall and you have no friends and no significant other because you can’t make time to meet anyone for dinner?

I’ve had employers bill me out at anywhere from $50 to $75 per hour. Under ideal conditions, where they drop the computer off with the expectation of getting it back within 2 weeks, I bill myself out at significantly less than that. But for on-site service at odd hours, I believe it’s perfectly appropriate for a computer professional to bill at those kinds of rates.

Even if you’re a hobbyist, you need to be fair to yourself. Computer repair is a skill that takes longer to learn than mowing lawns, and the tools required are every bit as specialized and every bit as expensive. In St. Louis, many people charge what amounts to $25 an hour to mow a lawn.

And? This doesn’t mean I never get computer-related phone calls. One Sunday when a family member called me with a noisy fan in a power supply, I found him a cheap replacement. I’ve fixed girlfriends’ computers before. The last computer I built was a birthday present for my current girlfriend.

But I’m not afraid to answer the phone, I don’t find myself giving people longshot answers just to get them off the phone long enough for me to go somewhere or start screening my phone calls. And I find myself getting annoyed with people less. Those are all good things.

Linux gets more attractive on the Xbox

There’s been another milestone in getting Linux running on Microsoft’s Xbox game console. It’s now possible to get it going if you bridge a couple of solder points on the motherboard to enable flashing the unit’s BIOS, then you use the James Bond 007 game and a save game that exploits a buffer overflow, and with a few more tricks, you can unlock the hard drive, put it in a Linux PC, install Linux, then move the drive back to the Xbox and turn it into a cheap Linux box.

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Help! I do tech support for everyone I know!

Here’s an interesting dilemma: How do you avoid becoming the primary technical support contact for all of your friends and family?
Richard “Rich Job” Jobity asked a really good question, didn’t he? I had to think about it for a while. That label fit me for a very long time. In the past year, it stopped, but I never knew exactly why. He made me think about it, and I found I’d done some interesting things on a subconscious level.

There was a time when I didn’t mind. I was 16 and still learning, I had some disposable time on my hands, and, frankly, I enjoyed the attention. You can learn a lot by fixing other people’s computers. And I used at least one of those friends as a reference to get my first three computer-related jobs. But over time, my desire changed.

I think a good first step is to identify exactly why it is you don’t want to be the primary technical support contact for all your friends and family.

In my case, I spend 40 hours a week setting up and fixing computers. And while I definitely spend some time off the clock thinking about computers, I also definitely want to spend some time off the clock thinking about something other than computers.

I have a life. I have a house to take care of, I have meetings to go to, and I have a social life. Not only that, I have bills to pay and errands to run, and physical needs to tend to as well, like cooking dinner and sleeping. And people get really annoyed with me for some reason if I don’t ever wash my clothes.

So if you get into a situation like I got into a year ago, when I had a friend calling me literally every night for a week with some new computer problem and keeping me on the phone for several hours a night while we tried to sort them out, I think it’s perfectly understandable for any reasonable person to be a bit upset. So here are my tips for someone who wants to head off that kind of a problem.

Have realistic expectations on all sides. So the first step is to make sure your friends and your family understand that you have responsibilities in life other than making sure their computers work. You’ll do your best to help them, but it’s unrealistic to expect you to drop everything for a computer problem the same way you would drop everything for a death in the family.

Limit your availability. Don’t help someone with a computer problem while you’re in the middle of dinner. You’ll be able to concentrate better without your stomach growling and you won’t harbor resentment about your dinner getting cold. Have him or her step away from the computer and go for a walk and call back in half an hour. The time away from the computer will clear his or her mind and help him or her better answer your questions. Don’t waver on this; five-minute problems have ways of becoming hour-long problems.

Here’s a variant of that. I had a friend having problems with a Dell. She called Dell. She got tired of waiting on hold. “I know, I’ll call Dave,” she said. “Dave’s easier to get ahold of than this.”

She may have tried to call me, but last week I was everywhere but home, it seemed. She didn’t leave a message, so I didn’t know she’d called. The moral of the story: Don’t be easier to get ahold of than Dell. Or whoever it was that built the computer or wrote the software.

What if I’d been home? It depends. If I’d been home and playing Railroad Tycoon, I’d be under more obligation to help a friend in need than I would be if I were home but my girlfriend was over and I was fixing her dinner or watching a movie with her. The key is to remember your other obligations and don’t compromise on them.

I remember a week or two ago, I was sitting on my futon with my girlfriend, watching a movie, arms entangled in the weird way the way they tend to do when you want to be close to someone. The phone rang. I didn’t move. “You’re not going to answer that?” she asked. “No,” I said. Since when is it rude not to answer your phone? They didn’t know I was home. If I don’t want to talk at that instant, I’m not obligated to. Besides, both of us would have had to move for me to pick up the phone. So I ignored it. She looked at me like I’d paid her some kind of compliment, that I’d rather stay there with her than yak on the phone. Call me old-fashioned, but that used to go without saying.

Whoever it was didn’t leave a message. If it’d been important, either they would have or they would have called me back. (Maybe it was the friend who’d thought of using me as a substitute for Dell tech support. Who knows.)

Don’t do a company’s work for them. If someone’s having a problem with a Dell, or having a problem dialing in to the Internet, I stay away from the problem. If a Dell is having hardware problems, the user will have to call Dell eventually anyway, and the tech will have procedures to follow, and there’s no room in those procedures for a third-party diagnosis. Even if that third party is a friend’s cousin’s neighbor who supposedly wrote a computer book for O’Reilly three years ago. (For all the technician knows, it was a book about Emacs, and you can know Emacs yet know a whole lot of nothing about computer hardware, especially Dell hardware. But more likely he’ll just think the person’s lying.)

And if someone can’t dial into an ISP, well, I may very well know more about computers than the guy at the ISP who’s going to pick up the phone. I may or may not be more intelligent and and more pleasant and more articulate than he is. But the fact is, I can only speculate about whatever problems the ISP may be having. And seeing as I don’t use modems anymore and haven’t for years, I’m not exactly in a good position to troubleshoot the things. Someone who does tech support for an ISP does it every day. He’s going to do a better job than me, even if he’s not as smart as I am.

Know your limits. A year ago, a friend was having problems with OS X. She asked if I’d look at it. I politely turned her down. There are ideal circumstances under which to try to solve a problem, but seeing the OS for the first time isn’t it. She called Apple and eventually they got it worked out. It’s a year later now. Her computer works fine, we’re still on speaking terms, and I still haven’t ever seen OS X.

Around the same time, another friend toasted her hard drive. I took on that challenge, because it was PC hardware and she was running an operating system I’d written a book about. It took me a while to solve the problem, but I solved it. It was a growth opportunity for me, and she’s happy.

And this is related to the next point: If you’re not certain about something, say so. It’s much better to say, “This is what I would do, but I’m really not sure it’s the best thing to do” than it is to give some bad advice and pretend that it’s gospel. Get your ego out of the way. There’s no need to try to look good all the time (you won’t).

Limit your responsibility. If your uncle has a six-year-old PC running Windows 95 and ran out and bought a USB-only printer because it was on sale at Kmart and now he’s having problems getting it running and he never asked you about any of this, how much responsibility should you be willing to shoulder to get that printer running?

I’m inclined to say very little. It’s one thing to give some bad advice. It’s another to be dragged into a bad decision. If the only good way to get the peripheral running is to buy Windows XP and wipe the hard drive and install it clean, don’t let that be your problem.

Don’t allow yourself to be dragged into giving support for free software downloaded off the ‘Net, supercheap peripherals bought from who-knows-where, or anything else you can’t control.

You can take this to an extreme if you want: Partition the hard drive, move My Documents over to the second partition, and then create an image of the operating system and applications (installed on the first partition, of course). Any time you install something new, create a new image. When your friend or relative runs into trouble, have him or her re-image the computer. He or she can reinstall Kazaa or whatever notorious app probably caused the problem if desired, but you can disclaim responsibility for it.

Which brings me to:

Disclaim all responsibility for poor computer habits. Gatermann and I have a friend whose brother repeatedly does everything I’d do if I wanted to set out to mess up someone’s computer. He downloads and installs every gimmicky piece of free-with-strings-attached software he can find, turning his computer into a cocktail of spyware. He runs around on Kazaa and other file-sharing networks, acquiring a cocktail of who-knows-what. He opens every e-mail attachment anybody sends to him, acquiring a cocktail of viruses. He probably does things I’ve never thought of.

Gatermann installed antivirus software on the computer, and we’ve both run Ad-Aware on it (if I recall, one time I ran it I found 284 instances of spyware). Both of us have rebuilt the system from scratch numerous times. The kid never learns. Why should he? Whatever he does, one of Tim’s friends will come over and fix it. (I guarantee it won’t be me though. I got sick of doing it.)

Some good rules to make people follow if they expect help from you:
1. Run antivirus software and keep it current. This is a non-negotiable if you’re running Windows.
2. Stay off P2P networks entirely. Their clients install spyware, and you know about the MP3 buffer overflow vulnerability in WinXP, don’t you? Buy the record and make your own MP3s. Half.com is your friend.
3. Never open an unexpected e-mail attachment. Even from your best friend.
4. If you don’t need it, don’t install it. Most free Windows software comes with strings attached in the form of spyware, these days. If you don’t want to pay for software, run Linux.
5. If you must violate rule 4, run Ad-Aware religiously.

And? This doesn’t mean I never get computer-related phone calls. A family member called me just this past Sunday with a noisy fan in a power supply. I found him a cheap replacement. I went over to my girlfriend’s family’s house Sunday afternoon and fixed their computer. (It made me wonder if the “4” in Pentium 4 stood for “486.” Its biggest problem turned out to be 255 instances of spyware. Yum.)

But I’m not afraid to answer the phone, I don’t find myself giving people longshot answers just to get them off the phone long enough for me to go somewhere or start screening my phone calls. And I find myself getting annoyed with people less. Those are all good things.

Update your BIND servers

A buffer overflow vulnerability exists in a large number of versions of BIND. CERT released an advisory over the weekend. I haven’t seen this on most news sites yet. Read more

Another RISC platform for Linux

Vintage workstations. I’ve read two articles this past week about running Linux or another free Unix on vintage hardware.
http://www.debianplanet.org/article.php?sid=605
http://www.newsforge.com/article.pl?sid=02/02/19/049208&mode=thread

And while I can certainly appreciate the appeal of running a modern free Unix on a classic workstation from the likes of DEC or Sun or SGI, there’s another class of (nearly) workstation-quality hardware that didn’t get mentioned, and is much easier to come by.

Apple Power Macintoshes.

Don’t laugh. Apple has made some real dogs in the past, yes. But most of their machines are of excellent quality. And most of the appeal of a workstation-class machine also applies to an old Mac: RISC processor, SCSI disk drives, lots of memory slots. And since 7000-series and 9000-series Macs used PCI, you’ve got the advantage of being able to use cheap PC peripherals with them. So if you want to slap in a pair of 10,000-rpm hard drives and a modern SCSI controller, nothing’s stopping you.

There’s always a Mac fanatic out there somewhere willing to pay an exhorbinant amount of money for a six-year-old Mac, so you won’t always find a great deal. Thanks to the release of OS X (which Apple doesn’t support on anything prior to the Power Mac G3, and that includes older machines with G3 upgrade cards), the days of a 120 MHz Mac built in 1996 with a 500-meg HD and 32 megs of RAM selling for $500 are, fortunately, over. Those machines run Linux surprisingly well. Linux of course loves SCSI. And the PPC gives slightly higher performance than the comparable Pentium.

And if you’re lucky, sometimes you can find a Mac dirt-cheap before a Mac fanatic gets to it.

The biggest advantage of using a Mac over a workstation is the wealth of information available online about them. You can visit www.macgurus.com to get mainboard diagrams for virtually every Mac ever made. You can visit www.everymac.com for specs on all of them. And you can visit www.lowendmac.com for comprehensive write-ups on virtually every Mac ever made and learn the pitfalls inherent in them, as well as tips for cheap hardware upgrades to squeeze more speed out of them. I learned on lowendmac.com that adding video memory to a 7200 increases video performance substantially because it doubles the memory bandwidth. And on models like the 7300, 7500, and 7600, you can interleave the memory to gain performance.

Besides being better-built than many Intel-based boxes, another really big advantage of non-x86 hardware (be it PowerPC, Alpha, SPARC, MIPS, or something else) is obscurity. Many of the vulerabilities present in x86 Linux are likely to be present in the non-x86 versions as well. But in the case of buffer overflows, an exploit that would allow a hacker to gain root access on an Intel box will probably just crash the non-x86 box, because the machine language is different. And a would-be hacker may well run into big-endian/little-endian problems as well.

http://homepages.ihug.com.au/~aturner/7200boot.html