Truecrypt is cross platform disk/file encryption software that is available for windows, mac os and linux. In order to get started visit www.truecrypt.org site and download the latest version of this software (direct link) and install it:

cd /usr/src
sudo -s
wget -c http://www.truecrypt.org/download/truecrypt-6.3a-linux-x86.tar.gz
tar -xvzf truecrypt-6.3a-linux-x86.tar.gz
./truecrypt-6.3a-setup-x86
exit

When installation is finished you will see Trucrypt item in Gnome menu (if not or use different X manager — type truecrypt in command line). Here how it looks like:

In order to create encrypted file press “Create Volume” button and follow instructions:

Use long passwords like “e07910a06a086c83ba41827aa00b26ed” instead of “123″ or “iloveyou”:

Once encrypted candy is created you can store it on usb flash drive or elsewhere, it doesn’t matter how that storage is formatted — it can be CD or windows formatter ipod.

Use the same utility to open the file — press “Select File” and point to newly created encrypted file, then choose first slot and select “Mount Volume” in drop down menu (it will ask for your sudo password and then password you typed when created the file):

As the result encrypted filesystem will be mounted into /media/truecrypt1 directory:

Copy your sensitive files there and unmount /media/truecrypt1 when done (select “Dismount” in drop down menu).
Good luck!

For rather long time I’ve been using gtkpod, amarok, banshee, exaile or rhythmbox to sync my ipod under Linux/Ubuntu and load my music collection there. As we all know The Elder Brother Apple fights with interoperability and makes ipod/iphone users to use iTunes only. Any other applications that can read/write to ipod data format are prohibited by Apple. This also concerns Rockbox and ipod4linux alternative firmwares — once Apple encrypted ipod firmware it became impossible to use them. It definitely sucks. At least due to the fact there are millions of Linux users who are real or potential customers of Apple products. Anyways these facts have been discussed in various forums, blogs like this and similar but this post about how to install Windows as the second operating system along with Ubuntu or any other Linux.

The first that we need to do is to create new partition for Windows and format it to NTFS. Exact steps to accomplish this depend on your HDD partition table e.g. there is one large ext3/ext4 partition for Ubuntu or there are several partitions for various distributions or mount points. Anyway you should use partition manager to create and/or format NTFS partition. I use gparted. It is graphical and it just works (use ‘sudo apt-get install gparted‘ if you run Ubuntu/Debian).

Second you should backup your MBR record and restore it after Windows installation that silently erases existing bootloader and installs windows one, use “dd if=/dev/sda of=/mbr.bin bs=446 count=1” to save MRB into mbr.bin file and “dd if=/media/sda/mbr.bin of=/dev/sda bs=446 count=1” to restore it from file to HDD.

To sum everything up here is the algorithm:

0. BACKUP ALL YOUR DATA!
1. Create NTFS partition using gparted.
2. Backup MBR using dd command e.g. “dd if=/dev/sda of=/mbr.bin bs=446 count=1″ (/dev/sda means your HDD).
3. Boot Windows installation CD and install it onto newly created NTFS partition.
4. Boot into Linux live CD  e.g. Ubuntu Live CD.
5. Restore MBR using dd e.g. “dd if=/media/sda/mbr.bin of=/dev/sda bs=446 count=1″.
6. Reboot.
7. Select Ubuntu in grub menu and boot it.
8. Setup grup for Windows booting.

In order to accomplish the last 8th item you should add the following text block to the end of grub config (read this article for detailed information):

title Microsoft Windows XP
root (hd0,1)
savedefault
makeactive
chainloader +1

Good luck!

P.S. If something goes wrong or you need more details you can take a look at the following article at ubuntu.com: Recovering Ubuntu After Installing Windows. It’s written in rather tangled manner but still informative.

# mkdir /tmp/ramdisk; chmod 777 /tmp/ramdisk
# mount -t tmpfs -o size=256M tmpfs /tmp/ramdisk/

where 256M is amount of RAM you wish to allocate for ramdisk. It’s clear that this value should be less than amount of free memory (use “free -m“). BTW, if you specify too many MBs for ramdisk Linux will try to allocate it from RAM and then from swap so resulting performance would be very poor.

GRE setup example topology

R1’s startup-config (part of it)

!

hostname R1
!
interface Tunnel0
description GRE tunell to R2
ip address 192.168.200.1 255.255.255.0
tunnel source 123.123.0.10
tunnel destination 123.123.1.10
!
interface FastEthernet 1/0
ip address 10.0.0.1 255.255.255.0
!
interface Serial1/0
ip address 123.123.0.10 255.255.255.0
serial restart-delay 0
!
ip classless
ip route 0.0.0.0 0.0.0.0 123.123.0.1
ip route 10.1.1.0 255.255.255.0 192.168.200.2
!

R2’s startup-config (part of it)

!

hostname R2
!
interface Tunnel0
description GRE tunnel to R2
ip address 192.168.200.2 255.255.255.0
tunnel source 123.123.1.10
tunnel destination 123.123.0.10
!
interface FastEthernet 1/0
ip address 10.1.1.1 255.255.255.0
!
interface Serial1/0
ip address 123.123.1.10 255.255.255.0
no fair-queue
serial restart-delay 0
!
ip classless
ip route 0.0.0.0 0.0.0.0 123.123.1.1
ip route 10.0.0.0 255.255.255.0 192.168.200.1
!

Results

R2#ping 10.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/17/28 ms

R3#ping 10.0.0.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.0.0.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/20/44 ms

One of the easiest way to try Chromium browser in Ubuntu Linux (Google Chrome browser for Unix/Linux operating system is named as Chromium) is to use daily binary builds at https://launchpad.net/chromium-project. Today Ubuntu is the most popular Linux disributions for desktops so there are daily builds available for the following Ubuntu versions: hardy, intrepid, jaunty, karmic.

First let your Ubuntu know where it should find chromium-browser deb package:

vi /etc/apt/sources.list

add the following lines:

deb http://ppa.launchpad.net/chromium-daily/ppa/ubuntu jaunty main
deb-src http://ppa.launchpad.net/chromium-daily/ppa/ubuntu jaunty main

Replace jaunty with hardy, intrepid or karmic depending which version you run at your computer. If you feel this information is not sufficient for you, follow this link to get Ubuntu official information on this matter or follow Launchpad help.

The next step is to install Chromium browser:

sudo apt-get update
sudo apt-get install chromium-browser
or
sudo aptitude install chromium-browser

Once you press enter Ubuntu will download around 18 MB of data from launchpad’s server and will install Chromium with gnome menu entries and shortcuts. Now you can go to System menu –> Internet –> Chromium Web Browser in order to launch Google browser.

Ubuntu Chromium Google browser (Google Chrome Ubuntu)

As you might know there is still no official release of chromium/chrome available for Linux, so these daily builds from launchpad are for testing/observations purposes only. For example, there is no flash plugin available so you will be able to see html pages like this one and no swf/flash content. Anyway thanks to Google for great browser which has all chances to become “browser number one” for Linux or even for the rest of operating system such as Windows or Mac. Who knows?

You might also find this page using Google and the following keywords: Ubuntu Chrome, Google Chrome Ubuntu, Chrome for Ubuntu and others.

Imagine the following situation: you have to compile some Linux/Unix application or kernel module that requires kernel source present at your hard drive, say, in /usr/src/kernels/kernel-2.6.21-i386/ or elsewhere. But there is not enough disk space to copy these sources or install kernel-devel or linux-source packages (in Fedora/RedHat or Ubuntu/Debian distros respectively)… Sounds familiar? Believe me, sometimes it happens

As a solution you can mount the directory of some remote PC that contains needed kernel source. It can be done via several protocols like smb, ftp etc. In this article we will mount remote directory using ssh protocol that is one the most popular for remote and secure access to Linux boxes over the network.

Below are the steps which should be taken to get the ball rolling. We need two packages: sshfs and fuse-utils.

1. Install necessary packages:

a. Ubuntu/Debian:

sudo aptitude install fuse-utils sshfs

b. Fedora/Centos/RedHat:

yum install fuse-sshfs fuse fuse-libs

c. Other Linux: download and compile sshfs/fuse from sources

2. Check that kernel module fuse is loaded:

lsmod | grep fuse

There should be the line containing “fuse” in the output (of not try modprobe fuse).

3. Mount remote filesystem using something like this (two commands):

mkdir -p /mnt/sshfs/
sshfs remote-user@remote-machine:/some/directory /mnt/sshfs

where remote-user is the username allowed to login remote-machine via ssh protocol. It will ask you to type the password so just type it and press return

4. That’s it. Good luck!

Apple iTunes is one of the most popular proprietary digital media players in the whole world. Using this no doubts outstanding application you can organize, play music/video files in very comfortable and user friendly way (it’s not an advertisement but real truth). Moreover iTunes is the only way to access Apple’s onilne music store and thus people often seeks the possibility to seamlessly access it after moving to Linux from Mac or Windows.

Well, unfortunately Apple doesn’t believe in magic so there is no native support of iTunes in Linux. At the same time none would deny that Wine does and guys from this project do their best to make things with iTunes in Linux better. In our example we use iTunes 7.3 which comes with Quick Time player 7.1.6, Apple iPhone support and of course iPods of any version, family and generation.

Install Apple iTunes 7.3 in Linux

1. Download iTunes 7.3 from apple.com or filehippo.com

2. Prepare Wine for itunes installation (if not installed do “apt-get install wine -y” or “yum install wine -y” in Ubuntu/Debian or Fedora/Redhat/Centos respectively):

$winecfg
wine: creating configuration directory ‘/home/artemn/.wine’…
fixme:midi:OSS_MidiInit Synthesizer supports MIDI in. Not yet supported.
wine: ‘/home/artemn/.wine’ created successfully.

Select your audio driver, it may be something like OSS or Alsa so use one u actually use Set Hardware Acceleration to “Emulation” option. All other Wine settings are per your consideration e.g. Graphics tab.

3. Update richedit30 (Win32 Cabinet Self-Extractor):

cd ~/.wine/drive_c/windows/system32
mv richedit32.dll richedit32.bak
mv richedit20.dll richedit20.bak
wine richedit30.exe

Set richedit20.dll and richedit32.dll as native through winecfg.

4. $wine iTunesSetup.exe
It will open iTune’s installation program under wine so you just install itunes as usually you did it in Windows. If error happens just re-run installer. See screenshot below:

5. Now you can start itunes and go through first run setup (all related screenshots are here). Just don’t care about errors thrown into the console:

$ cd ~/.wine/drive_c/Program\ Files/iTunes
$ wine itunes.exe

6. That’s it! Now u can use iTunes in Linux as you did it before in other operatin system:

P.S. By the way there are numerous Linux really native alternatives to itunes for comfortable music/video organizing and iPod management. At the same time latter can’t be as native and seamless as it’s in iTunes because those playes use Apple’s proprietary file storage system.

But I definitely recommend banshee, amarok and… exaile

What is .docx actually? It’s Microsoft’s file format representing word processor documents and named OpenXML (as an attempt to create open and free international standard). Today .docx is default format for Microsoft’s word processor Word.

There are myriads of online converters between OpenXML and OpenOffice formats including .docx, .xlsx, .odt and many etc but sometimes it’s much more better to just open received .docx file in Linux offline (if there is temporarily no Internet connection or for security/private reasons etc).

So, just download the following package to certain directory like /usr/src, here are the commands to do it:

1. cd /usr/src
2. sudo wget http://blog.mypapit.net/imej/odf_filter.tar.bz2

The next step is to unpack the contents of the archive (.tar.bz2 is definitely well compressed file) and copy 3 files to OpenOffice’s system directories:

3. sudo tar -xvjf odf_filter.tar.bz2
4. sudo cp OdfConverter /usr/lib/openoffice/program/
5. sudo cp MOOXTypeDetection.xcu /usr/lib/openoffice/share/registry/modules/org/openoffice/TypeDetection/Types/
6. sudo cp MOOXFilter_cpp.xcu /usr/lib/openoffice/share/registry/modules/org/openoffice/TypeDetection/Filter/

As you can see from picture below now it’s possible to natively open .docx files in openoffice under Linux. Of course such “native” support may imply some artefacts in opened files due to file formats incompatibility so it’s also a good option to ask your friends to convert .docs into .pdf before sending you

P.S. Thanks to guys from mypapit.

P.S. Here are several online converters .doc(x) <-> .odf <-> .pdf:

1. ZAMZAR (possibly the best converter), 2. http://docx-converter.com/.

1. mplayer (sudo aptitude install mplayer)
2. lame (sudo aptitude install lame)
3. win32 codecs (sudo aptitude install ubuntu-restricted-extras)

and then convert file.wma into file.mp3 using the following console command:

mplayer -vo null -vc dummy -af resample=44100 -ao pcm:waveheader file.wma;lame -m s -V 3 audiodump.wav;mv audiodump.wav.mp3 file.mp3;rm audiodump.wav

This also works for Fedora / Centos / Redhat family Linux distributions (requirements should be installed by yum package manager via third-party software repositories).

Done? Ok.

There is one public IP assigned to WAN interface of the router while FTP server (of course run by Linux as well) has IP something like 192.168.123.14 or 172.16.*.* or 10.*.*.*. Moreover you want to allow people to access your FTP from every corner of Internet… So, there are several ways how to apply this but let’s talk about how to achieve this by means of using port forwarding feature that is available in any router’s functions list.

So, let’s say we have the following configuration:

Internet <-> [a] router [b] <-> [c] FTP server

[a] is WAN interface with 212.213.214.215 (just an example) IP assigned to it, [b] is NIC with 192.168.0.1 and [c] is server’s interface with IP 192.168.0.2. All what we need is that users from Internet can access FTP server using 212.213.214.215 IP and default 21 TCP port.

One of the main problems is that passive mode of FTP service uses any port from range 1024 to 65535 so it’s not enough to forward 21/20 ports to FTP server and let the ball rolling. So, go to servers’ CLI and open configuration file of an FTP service. It would be vsftpd, proftpd whatever. Let’s say we have vsftpd so we have to add the following lines to /etc/vsftpd.conf:

pasv_min_port=12000
pasv_max_port=13000

When changes are saved restart vsftpd server.

Now access router’s CLI and type the following:

iptables -t nat -I PREROUTING -d 212.213.214.215 -p tcp -m tcp --dport 21 -j DNAT --to-destination 192.168.0.1
iptables -t nat -I PREROUTING -d 212.213.214.215 -p tcp -m tcp --dport 12000:13000 -j DNAT --to-destination 192.168.0.1

This will add netfilter port forwarding rules which will redirect traffic coming at routers’ public IP through 21 TCP port to FTP server and will properly handle passive FTP mode.

Wuala – it’s a finish.