Saving energy isn’t just the popular thing to do, it’s right thing to do. Whether you believe in the impact of society on global warming or not, you probably are still receptive to saving a few dollars on your electricity bill? All modern PCs behave quite nicely with Windows built-in power management features such as Stand By and Hibernate. While hibernate might be a tougher conversion to make due to it’s slower by design resume feature, stand-by is something the majority of us should use. Unless your PC is actually doing something while you are away from it, a properly functioning PC utilizing stand by can resume to a fully working state in mere seconds. Surely that is sufficient to 90% of the PC users out there?

Utilizing the built-in power management functionality on your PC is an easy way to save money – a PC running 24/7 in my area costs roughly $10-15 a month. While you won’t retire early on these savings it is essentially free money in my opinion. For those of you that care a bit more about the environment or are even more miserly, their exists a piece of software that may speak to you.

Granola is an energy saving software that works on both Windows and Linux. Using analysis and under-lying algorithms, Granola can further reduce your power consumption on your PC by focusing almost exclusively on the CPU. While all modern processors feature some sort of built-in energy management, either throttling down the clock cycles or core voltage and times of minimal use, they’re results are conservative at best. Granola can further squeeze out a few more pennies on the dollar while sitting quietly in the background. The effect is essentially transparent after the initial splash screen in my experience.

The main interface of Granola consists of many interesting statistics and some tangible analogies to the savings you’ve incurred. For example, while a number such as 50 kWh saved over the course of the year means little to most, Granola will instead present the information in how many hours you could run an air conditioner or refrigerator. You will also get a cost savings tracked throughout the use of the software assuming you provide your electricity costs in the options panel. It’s really a clever tactic that attracted the attention of someone like myself.

Granola is a free download and works on most Windows (and Linux) systems including Windows 7.

Download Granola

PuTTY is arguably the most popular free SSH client for Windows, likely found on every computer belonging to a user who knows what SSH is. I use PuTTY daily – it’s a single executable that does everything I need, quickly and simply. Well .. not everything I suppose. The lack of tab-based navigation has annoyed me ever since I had gotten used to the notion in Firefox. As my day progresses, it is not uncommon to have 4 or 5 PuTTY sessions going at once. This flies in the face of my desire for an organized taskbar, with windows just so. My workspace becomes cramped and my productivity lessens. I admit, it’s a subtle and minor annoyance but today I found an answer.

The PuTTY Connection Manager is a wrapper for the popular client. PCM encapsulates the original putty.exe binary in an attractive interface, complete with tabs and a few other niceties.

• PuTTY with tabs – swell!

• The connection manager on the right side can be configure to Auto Hide – much like the Windows taskbar.



• A new feature provided by PuTTY Connection Manager is automatic login as well as passing parameters to the PuTTY session on creation.

PuTTY Connection Manager requires Microsoft .NET Framework 2.0 and the original PuTTY Client – both of which are not included in the download. Even with the .NET requirement, PCM remains light-weight and snappy.

Nine months ago you did a good deed. In a valiant attempt to clean up your filesystem you compressed and archived a few directories and their contents. Decidingly clever, effort was put towards keeping prying eyes out and your data secure – a password was embedded in the archive file. Without the password, no one could access your data. Time has passed until today, when you’ve realized you need access to one of the files you’ve archived away. What was that password again? There is a solution to your predicament, RarCrack.

RarCrack is a Linux program that applies a bruteforce approach to cracking password protected rar, zip, and 7z files. Brute force has its limitations but in general, it can be quite effective. Besides, what other options do you have at this point?

Download

wget http://downloads.sourceforge.net/rarcrack/rarcrack-0.2.tar.bz2?modtime=1193432831&big_mirror=0

Install

Use

rarcrack your_encrypted_archive.ext [--threads thread_num] [--type rar|zip|7z]

Everything in [] are optional, rarcrack cracks with two threads by default and autodetects the archive type. If the detection is wrong you can specify the correct file type with the type parameter. RarCrack currently cracks with a maximum of 12 threads. After the cracking has started, RarCrack will print the current status to a file. If you want more specific password character set to brute force from, you need to run RarCrack to create the XML status file (3 sec).

Here is a sample XML file with a password character set:

<?xml version=”1.0″ encoding=”UTF-8″?>
<rarcrack>
<abc>0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ</abc>
<current>uU</current>
<good_password></good_password>
</rarcrack>

With a bit of luck you will be able to determine the necessary password. In the same vain, you should take caution in just how easy this can be to crack the next time you wish to password protect a file.

GNU wget is a free utility for non-interactive download of files from the Web, generally available on most Linux installs.  It supports HTTP, HTTPS, and FTP protocols, as well as retrieval through HTTP proxies. Wget is non-interactive, meaning that it can work in the background, while the user is not logged on.  This allows you to start a retrieval and disconnect from the system, letting wget finish the work.  By contrast, most of the Web browsers require constant user’s presence, which can be a great hindrance when transferring a lot of data.

One of the powerful features of wget is its ability to retreive a complete mirror of a website, locally, on your hard drive. It is also intelligent enough to only download links or files associated with the website, without traversing external links. Though it would be a generous public service, you probably wouldn’t want to mirror the entire Internet!

Here’s how you do it.

From a Linux shell:

$ wget -mk -w 10 http://www.google.com/

• -m instructs wget to enter mirroring mode
• -k instructs wget to convert links in the webpages downloaded to local links
• -w 10 instructs wget to delay 10 seconds between requests. This is really just to maintain proper net etiquette; it’s not required

Not running Linux or otherwise have no access to wget? Don’t fret, wget has been ported to Windows. Wget is a powerful utility that I’ve barely scratched the surface here. Find out more on wget by reading the associated manpages.

In my day to day profession I am often tasked to find out where all the storage space has gone on a system. For example, I need to figure out which user(s) are using more than their fair share on the mail server. Knowing that the mail folder resides under /home, I need a quick and easy way to list all of its subfolders sorted by size.

Thankfully, Linux makes this a rather trivial process – assuming you know the right command and appropriate flags:

du –max-depth=1 /home/ | sort -n -r

In Unix, it is equally similar:

du -sk /home/* | sort -n -r

Either command, when executed, will dump something similar to the following:

1234881 /home/
23441 /home/adam
19244 /home/support
13960 /home/admin
…

..on your screen. Now, you can get to cracking those knuckles on your top spacepigs!

vi is a powerful text editor found on practically every Unix based system. Consequently, it is quite beneficial to learn and master vi and its abundance of keyboard shortcuts. If you are not quite the guru you hoped to be, here is a handy reference page that will bring you up to speed quickly.

File Handling

vi
Open a  file to edit

:w
Save a file

:w
Save a file with a new filename

:q!
Quit without saving

:wq
Quit and save

Movement

h or (left arrow key)
Left one character

i or (right arrow key)
Right one character

k or (up arrow key)
Up one line

j or (down arrow key)
Down one line

^
Beginning of a line

$
End of  a line

1G
Beginning of a file

G
End of a file

:
move to line number

Editing

i
Insert text

A
Append text

r
Replace text

R
Replace a character

x
Cut/delete character

dd
Cut/delete line

D
Cut/delete to end of line

Y or yy
Copy line (yank)

p
Paste line

J
Join line below to this line

u
Undo last change

e
Undo all changes

Advanced Users

/ &/ (repeats last search)
Search for keyword

:set number & : set no number (turns off numbers)
Show line numbers

.
Repeat last command

:m//
Regular expression search

:s///
Regular expression replace

:,s///
Regular expression replace by lines

:
Repeat command x times

%
Find matching () or {}

:sh (type exit to return to vi)
Drop to shell

[tags]Unix, vi, Linux, vi shortcuts[/tags]

I recently migrated my network storage server, running Ubuntu Linux incidently, to a software RAID 5 configuration. RAID level 5 requires atleast 3 harddrives; giving you in total N-1 storage, where N is the number of disks in the array. For my deployment, I used 3 120GB drives (mixing IDE and SATA, Linux is indifferent here) giving me effectively 240GB. The missing 120GB is the parity information that allows transparent data recovery when 1 disk in the array fails. I’ve glossed over a lot of the details regarding RAID 5 but a quick google should fill in the blanks if need be.

Here is how I accomplished this under Ubuntu Dapper.

1. Install mdadm using apt-get, or your favorite package manager. mdadm is the tool used to administer Linux md device arrays (software RAID).
2. Partition your drives as appropriate using cfdisk /dev/hd<?>. Ensure that all partitions are of equal size and the partition type is set to Linux raid autodetect.
3. Using mdadm create your RAID-5 device:
   • mdadm --create /dev/md0 --chunk=64 --level=raid5 --raid-devices=3 /dev/hdc1 /dev/hde1 /dev/sda1; substituting for your own /dev/ devices.
4. Good Good.
   • # cat /proc/mdstat
     Personalities : [raid5]
     md0 : active raid5 sda1[0] hdc1[1] hde1[2]
     234371968 blocks level 5, 64k chunk, algorithm 2 [3/3] [UUU]
5. Format your newly created /dev/md0 device.
   • mkfs.ext3 /dev/md0
6. Create a mount point for your RAID-5 array and add it to /etc/fstab so it is mounted automagically on the next reboot.
   • /dev/md0 /storage ext3 defaults 0 1
7. Getting detailed info about your array.
   • # mdadm --detail /dev/md0
     /dev/md0:
     Version : 00.90.03
     Creation Time : Sat Apr 1 14:01:39 2006
     Raid Level : raid5
     Array Size : 234371968 (223.51 GiB 240.00 GB)
     Device Size : 117185984 (111.76 GiB 120.00 GB)
     Raid Devices : 3
     Total Devices : 3
     Preferred Minor : 0
     Persistence : Superblock is persistentUpdate Time : Tue Apr 18 07:39:21 2006
     State : clean
     Active Devices : 3
     Working Devices : 3
     Failed Devices : 0
     Spare Devices : 0Layout : left-symmetric
     Chunk Size : 64K

     UUID : 51dec40b:2d6fd4cc:a9e0addc:fe5303d4
     Events : 0.176640

     Number Major Minor RaidDevice State
     0 8 1 0 active sync /dev/sda1
     1 22 1 1 active sync /dev/hdc1
     2 33 1 2 active sync /dev/hde1

8. Managing the RAID device.
   • Setting a disk faulty/failed:
     # mdadm --fail /dev/md0 /dev/hdc1
   • Removing a faulty disk from an array:
     # mdadm --remove /dev/md0 /dev/hdc1
   • Clearing any previous raid info on a disk:
     # mdadm --zero-superblock /dev/hdc1
   • Adding a disk to an array:
     # mdadm --add /dev/md0 /dev/hdc1

RAID can be an intimadating piece of technology but it’s benefits are plainly obvious. Hopefully this framework howto is enough to ease your fears.

I’ve come across this problem in my profession and my solution is much simpler and easier to understand than the one proposed in this verbose write-up.

#!/bin/bash
if [ `date --date="+1 day" +%d` = 01 ]; then
execute desired task
fi

Have cron execute this bash script at the desired run-time each day to achieve the desired results.

Plug. Chug. Done.

read more | digg story

1) Get tiger-x86.tar.bz2

2) Unpack tiger-x86-flat.img to a separate NTFS hard drive

3) Load up the system with the Knoppix Live CD

4) If the drive from step 2 is external, attach it and let Knoppix automount it

5) Open up a terminal

• Use su to become root
• Switch to the directory Knoppix mounted from step 4 (look in /mnt/)
• Execute ls –all to verify that the .img file exists
• Execute dd bs=1048576 if=./tiger-x86-flat.img of=/dev/hda, where hda is the *drive* you wish to install to. hda=drive 1, hdb=drive 2, etc

6) When it has finished copying, reboot and select the drive you want as the startup from the BIOS or boot menu

7) With some luck, you should be staring at an Apple logon screen

• If the system hangs, Boot into safe mode by using the –x parameter at the Darwin boot screen

Log in as “deadmoo” password “bovinity”

9) Create your own account, Apple Menu->System Pref-> Users.

10) Relogin as yourself. It is safe to remove “deadmoo”

11) Finally, delete the file /System/Library/Extentions/AppleTPMACPI.ktext

• Hold down the Windows key and empty trash if the system complains the file is in use
• Reboot

12) Profit!

First off, I have to admit how amazed I was over the simple installation. That being said, realize what you are doing and what could happen if things go wrong. I merely claim that this “Worked for Me.”

• Connect your mini to your computer, ensuring that it is enabled for disk use.
• Download the iPod Linux Installer, the latest kernel.bin.gz, and the latest podzilla.gz.
• Unzip the three packages you’ve just downloaded.
• Rename file date-podzilla to podzilla and copy to the root of the mini.
• Rename file date-kernel.bin to linux.bin and replace the linux.bin inside the iPod Linux Installer folder.
• Run and install ipodlinux-installer. Choose to update the firmware, making sure to keep Apples firmware as the default boot order.
• Basically what you’ve just done is create a multi-boot option for your iPod, much the way you would dual boot Linux and Windows.
• Lastly, copy the file \4gipl\start to the root of the mini, replacing the existing file.

That’s it! Reboot your iPod mini (hold select and play buttons for 5-10sec). After reboot, hold the Rewind button; you should see the familiar linux text boot scroll.

Caio