Posts Tagged ‘Linux’

Some of you may remember in the movie Jurassic Park where the park founder’s granddaughter Lex, played by Ariana Richards, sits down at a computer terminal, gasps, and says “This is Unix. I know this!” That particular film moment has always resonated with me as a victory for realistic depiction of computer systems – the interface used in the movie is called fsn and was an actual Unix file manager – in an industry rife with horrific exaggerations; Swordfish, anyone? I’m sure there’s an unwritten story as to how she (or her brother if you follow the book) gained her skills at a computer system that in 1993 was almost exclusively relegated to universities. However, I digress.

Shortly before that scene was another scene and catchphrase that should resound with familiarity to system administrators around the world. In the face of marauding dinosaurs and computer sabotage, the character John Arnold, played by Samuel L. Jackson, must sacrifice what I’m sure was an absurd amount of uptime by killing the power and rebooting the mainframe. Would the system come back up? Would everything load up as needed to get the park’s systems back online? John’s mantra was simple: “Hold on to your butts!”

Every day as a Systems Administrator I’m faced with a comparable (though far less exhilarating) situation. Linux is an extremely stable operating system, and I have logged into systems that have been online for quite literally years. Eventually, though, kernel updates or stray mounts necessitate a reboot. Will the server’s filesystems need a check on reboot? Will the server even come back up? When a server’s been online for that long, the only way to know is to “throw the switch” and cross your fingers.

One way to have a better idea of how your system will behave during reboots in a production environment is to take the time to update your kernel once a month or so and perform a reboot to make sure the update sticks. This allows routine file system checks to take place as necessary and keeps your system abreast of the latest kernel updates. It also familiarizes you with how long the process takes, what sort of caveats you may run into, and reduces the overall surface area of your server to outside attackers.

In the last year, I have seen at least two exploits that can give an attacker root access to a server running an outdated kernel using common toolkits that can attack commonly deployed Content Management Systems with trivial effort. Compromising an unprivileged user account gives an attacker even more leverage against unpatched systems. Google CVE-2009-2695 and CVE-2010-3081 if you don’t believe me.

If you run a production system or even a backend system that is exposed to the big, bad Internet, it is absolutely essential to make sure that your kernel, software, and security measures are up to date. Today’s Slashdot article is tomorrow’s exploit.

What lesson can we learn from the unfortunate folks at Jurassic Park? Don’t assume your server is safe and don’t wait until there are velociraptors roaming your halls looking for a snack to perform proper maintenance on your system.

-Adam

Resolutely pointing off into the starry void of space on the bridge of the Enterprise, klieg lights gleaming off his majestic dome, Captain Picard causes the Starship Enterprise to leap off on another mission. Once asked how the “warp drive” worked on Star Trek, Patrick Stewart claimed that “I say Engage and we go.” Best explanation of warp drive I’ve ever heard.

I find I miss my Linux install. Due to circumstances beyond my control (i.e. I’m too lazy to stop being lazy), and the fact that few games work well on Linux without lots of under-the-hood tweaking, I broke down and bought a Windows installation for my PC. In between mining asteroids in my Retriever Mining Ship and solving 3D puzzles with a transdimensional gun, I do normal work with my computer; programming, web design, web browsing, video editing, file management, the whole deal.

Windows Vista, however, has a new feature that makes my work awesome. No, I’m not talking about the 3D accelerated desktop with semitransparent windows (although that IS awesome). I’m talking about the new Start Menu search box.

In Windows XP (I’m doing this right now), hitting the Windows key opens up the start menu. I can either use the mouse to navigate the menu (why use the start key if you’re going to mouse the menu?), or navigate with the keyboard arrows. However, this can be quite tedious and slow. If I remember the program’s “.EXE” name and the program is on the Windows System Path, I can select “Run…” and type in the name, like wmplayer for Windows Media Player. But the names are funky and again, the cool programs aren’t on the path.

In Windows Vista, however, when you bump the start menu, a new device, the SEARCH BOX, is automatically engaged in the start menu! So, when I want to use, say, Notepad, I type ‘windows key notepad enter’. Goldwave (sound recording) is ‘windows key goldwave enter’. When I want to use a Open Office tool, I bump the Windows key, type “open office” and then select the tool I want with the arrow keys, as the search box narrows down the huge Start Menu to just the entries that make sense. Even cooler: when it’s budget time, I hit the Windows key then type “budget”. Search brings up “Apartment Budget.ods”. Select that with the arrow keys, and it opens Open Office Calc (spreadsheet) for me.

It’s like having a command line in Windows. Any program is just a few keystrokes away, and for a Linux nut and a touch typer like me, means that my computer is that much more efficient. I don’t need muscle memory with the mouse to navigate the start menu, I don’t have to squint at the menu items and find my program. I just have to remember the name!

Try it some time. It’s almost as awesome as saying “Engage” and going to Vulcan.

-Shawn