Linux Cookbook

Linux tips, hints and how-to's.

Here are some tips, hints, and how-to's for Linux fans of all stripes. But don't just read the articles--keep going for even more help and insight from the readers' comments.

• Lazy Linux: 10 essential tricks for admins from IBM developerWorks comes this nice little collection of very neat tricks, including how to recover your root password, unmounting an unresponsive DVD drive, and more.
• 10 ways to make Linux boot faster includes even more tips on how to streamline your system's boot performance--and at the same time, performance in general. Simplify, simplify.
• Anatomy of the Linux file system is another nice, comprehensive and technical overview to the Linux file system. And it's from IBM developerWorks, so you know it's accurate.
• CLI Magic: For geek cred, try these one-liners is a nice, quick introduction to using pipes at the command line, as well as doing some text processing with grep and gawk. From Linux.com.
• Easily Password Protect a Website or Subdirectory OK, so this one isn't strictly Linux, but it's nice to know how to do it.
• Sync and Back Up Your Data with Conduit for Linux While it's great to have yet another tool for backup, there's more to Conduit than just backups. Check it out!

Let me know how you like these links--and if you have any good ones to add!

Good advice about backups

There are many approaches to doing backups. Unfortunately, most of them are some variation of "it's too much trouble". But even if you are doing backups, this article reminds us that Your backup is only as good as your last restore.

Which brings me to another article about backup, this one much more technical and complete, from IBM: Automate backups on Linux. Maybe not everything you need to know about automating your backups, but it's a good place to start if you need to know your backups are being done, and being done securely.

Command line-fu from Foogazi

You only really get better at the command line by using the command line, so it might seem counter-intuitive to write about 10 Linux Commands You Probably Don’t Use. If you don't use the command line, there's a lot more than 10 that you don't use--but if you do use the command line at all, or what to use it more, definitely read that link.

Check out Foogazi for more Linux tips/news/etc. The last week or so seem to have been heavy on the "what's so great about Linux" articles that Linux-lovers always love, but there's plenty of other how-to goodness in there.

More Linux Tips from IBM

There are good reasons so many Linux wizards like, no, LOVE the command line. If you know what you're doing, it can be way faster and easier to use than fiddling around with mouse pointers and windows and so on.

IBM is a great resource for Linux how-to (see IBM: Great stuff, hard to find), and here's another excellent article: UNIX tips: Learn 10 more good UNIX usage habits. Which is, in turn, a follow-on to the also excellent article UNIX tips: Learn 10 good UNIX usage habits by Michael Stutz.

Enjoy!

The Ultimate Unix Toolbox?

Unix Toolbox is not for newbies. It's the real stuff: command line commands that you need if you're doing real work with real systems. Want to set disk quotas? Change MySQL logins? Set file permission? Encrypt partitions? All those questions, and more, are answered here.

Warning: if you don't know what those things are (or even if you're not sure), Unix Toolbox probably isn't for you. If you want to know what those things are, check it out when you're ready to experiment.

Open Source Software bringing down hardware costs?

Ever wanted a very serious server for cheap? Here's one way: Build a quad-core, 8-gig server for $900. It runs Linux. You'd have to a few hundred bucks (at least) if you wanted it to run Windows, though.

Remember the 1980s? When everyone was investing big bucks in their own PBX systems? Well, guess what. One open source project, Asterisk, is changing that entire (big) business. Here's Forbes' take on the new world of open source PBX, Dial D for Disruption.

We've had these incredibly great, vastly powerful, little PCs sitting on our desks for the past quarter century, and most of the cycles have been going to running solitaire or screen savers. The great thing about open source is that it gives smart people ways to figure out how to make all these great computers actually DO things of value, especially things that previously would have required expenditures of hundreds of thousands of dollars for specialized (that is, proprietary) hardware and software.

At the very least, I hope developments like these will spur the big, established firms into action in the R&D front. Because too many have gotten used to slapping their software into COTS components, slapping their logos on the boxes, and shipping them out to big, deep-pocketed companies. If you can build your own, adequate, PBX for $100, then commercial PBX vendors need to start building better--much better--PBXs.

Make your own dancing GIFs, with Open Source Software

This, Making Animated GIFs With Free Software in Four Steps, is just the kind of "howto" article that I like best: it explains what you're trying to do, tells you just enough to do it, and gives a couple of examples. Nice!

Linux on Little Laptops

Got an old laptop? I do: it's about ten years old and almost ludicrously out of date. A Sony Vaio with 192Mb of RAM and a 5Gb hard drive.

I've also got a brand new laptop, the Asus Eee PC. But don't bother too much with the "official" site, there are better places to get more info on the Eee, starting with Amazon.com. You can learn a lot from the customer reviews. But here's the best resource I've found so far: Eee User is the "Unofficial Asus Eee PC" blog/forum/wiki/community, and they've got articles and links to resources for turbocharging this little laptop.

If you're thinking about buying an Eee, here's fair warning: the default user interface is kind of dreadful. It reminds me of those little PDAs that were all the rage 5-10 years ago, that had teensy-tiny QWERTY keyboards and fit in a (big) pocket. But the Eee is big enough to run an actual desktop environment, even if the screen is a bit pinched, so why not?

Anyway, this post is going to be a catchall, covering not just ways to fiddle around (and potentially brick) your Eee, but also going into some of the options available for running Linux on laptops (old and new) as well as turning a USB drive into a portable workstation. Now, that idea is hardly news (I wrote about my experiment with a LiveCD and a USB drive back in the March 2005 Computer Power User Magazine, "My Knoppix Adventure"), but what is news is that people are actually starting to do it.

For example, here's a nice writeup: Travel Without the Laptop, Carry Your Computer on a USB Drive that's not even about Linux, but there's a very good warning in the comments about keyloggers, which can be either hardware or software that records all the keystrokes you enter on a computer. Google them up yourself, and you'll find that they can be integrated into the actual keyboards of public computers, so you might want to be wary of using any PC that you don't own--meaning that the Eee is an even better option than you might think. I'd rather drag a 2-pound Eee PC around and be safer than jettison my own hardware entirely.

Anyway, without any more ado, here's some links about fiddling around with the Eee:

• Want that "advanced" mode? Here's how to Enable Advanced Desktop Mode from EeeUser.com. Be sure to read the whole thing; I skipped to the end and got myself in trouble (had to boot from a USB drive to fix it), but when I started over from the start ("the easy way") I ended smiling.
• I've been happy, so far at least, with the half-gig of RAM that came with the Eee, but if I decide to upgrade it, I'll be going back to this video, Bleeding Edge TV 207: Asus Eee PC RAM Upgrade, which makes it look very easy. I found the video from this writeup, Asus Eee PC: How to Upgrade the Memory, also worth reading.
• There's a lot more you can do, but check out the EeeUser.com wiki for some ideas if you're not sure what you want to try.

But meanwhile, what about booting from a USB stick? I had to do that when I charged ahead and "edited" a configuration file that caused my Eee to fail to boot. Once I booted Linux from USB, I could "correct" that edit and recover my system. Long story short, the answer for me was Damn Small Linux because the only USB drive I had handy was just 256Mb, and all the other how-to's I found listed required ingredients that began with "IGb or greater USB drive". DSL is just awesome, and it works so well. All I had to do was burn the distro to CD, boot it on any old system with the USB stick plugged in, and run a quick little app from the DSL Apps/Tools menu to transfer the OS to the USB stick.

OK, so what about all those other cool options for running Linux in super-portability mode? Here are some links, with my comments:

• Here's an Ubuntu wiki page about Booting from USB with Ubuntu. It's long, and presumably it applies to any flavor of Ubuntu, including Xubuntu (for older/lightweight systems, it uses Xfce4 as its desktop environment, rather than the weightier GNOME or KDE) and Fluxbuntu (uses Fluxbox, which is another lightweight desktop manager).
• If you're curious about Fluxbuntu, you can read one person's adventures with Fluxbuntu on my Low-end Laptop. And, if you're interested, you can check out the back story here, Low-end Laptop Distro thinking again...
  
• Damn Small Linux is the bomb. I just love it: it boots so fast and looks so smooth you'd never suspect it's only 50Mb. Just had to give it another link here.
• Puppy Linux is another distro designed to give new life to old systems with minimal RAM and CPU. That's what's driving my Vaio these days; it's also pretty elegant and small (if not as small as DSL).
• gOS. It's not Google Linux, but it's what Google Linux might look like, if it existed. Even though it's just another flavor of Ubuntu, it's a Google-leaning flavor, which is a good idea for keeping the size down. Google Applications, after all, live on the web, not on your hard drive. gOS also happens to be the Linux flavor that Walmart uses for it's cheap-o Linux PCs, for whatever that's worth.
• Not sure what to make of Pendrivelinux.com, with its "Boot and run Linux from a USB flash memory stick" heading on the homepage. Lots of tutorials on booting and running Linux from a USB flash memory stick, but not so much context.

Finally, if you've got an old laptop, you might like to read Give an Old Laptop New Life with Cheap (or Free) Projects  from Lifehacker, with some pointers to distros already cited above as well as hints about deploying laptops for various uses (I'm thinking my old Vaio, with a wireless LAN card, could work a treat in the kitchen).

This is what computing is all about

One key--but unstated--objective of commercial operating systems (that is, Windows and Mac) is to make using a computer like using a car. The idea is to hide all the messy technology bits.

The problem with that approach is that the OS designers assume they know exactly what all users want to do. So, you get the traditional three-panel graphical file browser model, for example. But if you want some feature or function that the OS designers didn't foresee you would want, you're often out of luck with Windows/Mac OS.

Not the case with Linux. Check out Display Structure of Directory Hierarchy for a one-line Linux command that will display your system's directory hierarchy. Sure, it's a complicated little command:

ls -R | grep ":$" | sed -e 's/:$//' -e 's/[^-][^\/]*\//--/g' -e 's/^/   /' -e 's/-/|/'

but with Linux, that can be turned into a shell script, which acts like any other command line command.

What NOT to do with your old computers

Why not throw away your old obsolete PCs when you can re-purpose them as a file/print server, firewall or some other single-purpose appliance? People have been doing this forever--at least since about 1988, when those old dual-floppy IBM 5150 PCs started getting obsoleted by PCs powered by Intel's 386-based processors, and businesses were installing Ethernet-driven, Novell-powered LANs.

What could be more sensible than to re-use older PCs that aren't fast enough to use for desktop computing anymore? It's far better than simply throwing out the old machinery, which is full of toxic waste. I'm as guilty as anyone of promoting the idea of re-using old PCs for this kind of thing, but I wonder why people are still promoting it, as in this article, "Simple Home File Server (Based On Ubuntu)". I love HowtoForge, but this is kind of silly for home/family users, and here's why:

• Yes, it's great to have a family file server for backups, for file sharing, and so on--but where do you put that system? You've got to find a place for it, which means giving up some of your precious living space for an appliance that you've been getting long without just fine, so far.
• Yes, you avoid paying for a new computing appliance (were you going to buy one anyway), but you're stuck with an older, full-powered, general-purpose computer to do a single task. That means running a key function in your household network on old equipment (think about that 10-year old hard drive, for example).
• Power. A PC sucks up the power big time, and if you're going to use it as a household server, you need to have it running all the time. If you power it on and off a lot, you'll further tax the old, possibly nearly worn-out, equipment even further. If you keep it on all the time, you've got to pay the electricity company to keep that CPU cycling, the fans running, even the graphics card adapter (which you may not even be using if you're running headless).
• Failures. Did I mention this? Well it's important, especially if you think you can save a couple hundred bucks on a firewall/gateway by using an obsolete PC. Dell and HP expect you to upgrade your PC every 3-5 years, so they don't waste engineering on making hardware that'll last for 10 or 15 years.
• Complications. You've got to keep up with security patches on that system, not to mention general upkeep and maintenance. You'll need a surge protector at least, if not a full-battery backup system as well as network connectivity. You've got to dedicate a power outlet to the system. Don't forget how annoying the buzz of fans and disk drives can be, so you may want to avoid using an old PC to drive an entertainment system. And so on.

The thing is, we're at the point where most of the functions you can use an old PC for can more economically be incorporated into single-purpose appliances (like the iPod, for example). Why run a full-blown PC as a printer server when you can buy a printer with the required functionality built-in? Why run a full-blown PC as a file server when you can buy a solid state USB file server?

So, what should you do with an old PC? I don't know what the answer is these days. In general, schools and charities aren't any more interested in using ancient computers than you or I; so you might not be able to find anyone interested in accepting them as donations.

What do you do with your old PCs?