linux-minds

One line Python Web server

2011-12-15T05:45:00.001-08:00

if you have python installed, go to your terminal. Go to the directory you want to serve HTML files from, then type one of the following, depending on your python version:

Python 2.x:

python -m SimpleHTTPServer

Python 3.x:

python -m http.server 8000

Get Notifications from Your Scripts with notify-send

2011-12-12T09:37:00.000-08:00

Notify-send is a great application for notifying you when an event has occurred. An event such as a script running to completion.

If notify-send is not installed on your machine already, install the package "libnotify1" (or possibly just "libnotify") from your repositories.

Once installed you can simply type the following, at the command line, to display a pop-up message near your system tray:

notify-send "hello"
By default the message will be displayed for 5 seconds. To change how long a message stays displayed use the "-t" switch. This will change, in milliseconds, how long the message is displayed. Enter "-t 0" to leave the message up until the user closes it.

notify-send "This message will be displayed for 3 seconds" -t 3000
notify-send "Click me to close me." -t 0

You can even add a title and an icon to the notification.

notify-send "This is the Title" \
"Check out the cool icon" \
-i /usr/share/pixmaps/gnome-terminal.png

When used in a script you could set it to notify you periodically by placing the command in a loop:

#!/bin/bash

while [ 1 ]; do
notify-send "Up Time" "`uptime`"
sleep 5m
done

Disabling Bash History Temporary

2011-12-12T07:51:00.000-08:00

Say that you’ve got to pass some password as command line argument to something. It would probably be a bad idea to store it in your ~/.bash_history, but clearing the file isn't desired either. So you need to temporary disable the command history for the current session. You can do it by unsetting the HISTFILE environment variable.

unset HISTFILE

The result is that while the session is active you can access the history as usual, but it won't be saved to the disk. History for other sessions, will behave as usual.

Vim Selections

2011-08-25T12:19:00.000-07:00

how to ssh without password

2010-02-03T04:51:00.000-08:00

Let say you want to access to a machine with IP 192.168.1.10, and make sure you have
command ssh, ssh-keygen, ssh-copy-id.
First, generate the ‘key’, the key will be used to open the remote machine’s door.

ssh-keygen

You will see something like that

Enter file in which to save the key (/home/myname/.ssh/id_rsa):

Whatever it appears just press enter until it ends, press enter for passphase as well.
Okay, the ‘key’ will be generated, something looks like ~/.ssh/id_rsa.pub
Copy over the ‘key’ to remote machine, and enter your password

ssh-copy-id -i ~/.ssh/id_rsa.pub macspc@192.168.1.10

Done. Now you can ssh 192.168.1.10 with username macspc without password.

ssh macspc@192.168.1.10

What I Did

~? ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/home/brijith/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/brijith/.ssh/id_rsa.
Your public key has been saved in /home/brijith/.ssh/id_rsa.pub.
The key fingerprint is:
4b:71:39:69:36:13:0a:69:65:21:de:5f:24:b4:1c:b6 brijith@Newmegadisk
~? ssh-copy-id -i ~/.ssh/id_rsa.pub macpc@192.168.1.10
29
Password:
Now try logging into the machine, with "ssh 'macspc@192.168.1.10'", and check in:
.ssh/authorized_keys
to make sure we haven't added extra keys that you weren't expecting.

Now you can login through ssh with out a password

ssh macspc@192.168.1.10

It wont ask password any more.

If you want to launch application of the remote system in your PC using ssh use -X option of it

eg:

ssh -X macspc@192.168.1.10

and then give the application name you want to launch in resulting terminal
eg:

gedit&

This will launch gedit of remote system in your system

gedit

Password Less Dump in MYSQL

2010-02-03T04:47:00.000-08:00

MySQL is perhaps one of the most popular database systems currently available. It has a lot of great features, it's open source, and a lot of Web-based applications use it for their back-end storage.
One important part of running a database is maintenance, and that includes backups. However, due to the fact that the database is password-protected, one can't automatically back up the database without interactively supplying the password. And, depending on what you need to back up, you may even have to use the MySQL "root" user to do a full backup.
You can avoid those hassles by creating a configuration file for the user to do the backups (i.e., /root/.my.cnf). This user does not need to be the system root user; it can be any normal system user who has access to the database as the database's root user. The ~/.my.cnf file would look like:

[mysqldump]
user = root
password = secret

With this, you can automate a dump of the database via a cronjob, without being asked for a password. You will still need to supply a password using the mysqladmin or mysql tools, but not with mysqldump. Now, to automate the backup, run the following script out of cron:

#!/bin/sh
mysqldump -u root --all-databases >/var/lib/sqldump/mysql.dump

Some people may consider this horribly insecure, but it's no more insecure than doing it manually, especially if this is being done by the root (or even mysql) user. If the file is adequately protected (mode 0600), your database is just as safe. Remember that an attacker would have to obtain root privileges in order to read the file. If that attacker had root privileges, they could simply make a copy of your database, retrieve it, and open it on any MySQL installation at their home and be able to read the contents of your database at their leisure, without once requiring the database password.
Because there is just as much (or just as little, if you prefer) security in supplying the database root password in a configuration file, there is really no reason not to do it. The benefit is that providing password-less access can make things like automated database maintenance far easier.

Setting Up offline multiple language dictionary in Ubuntu

2010-02-03T04:27:00.000-08:00

All of you might have see a Dictionary application Under Office Menu in every Ubuntu distro. By default it is configured to work with online dictionary server. So the people we have an Internet connection will miss this application. No,not really,It is possible to configure so that it can work well as if it is online. following are the steps

Start Up synaptic and find the following packages and mark for installation

dict
dictd

these are the server and client for a dictionary services

apart from the above if you continue searching in sequence (to the above mentioned packages) you will find a whole lot of dictionaries -the ones i have installed are

dict-bouvier
dict-devil
dict-elements
dict-foldoc
dict-freedict-eng-deu (english to german)
dict-freedict-eng-hin (english to hindi)
dict-freedict-hin-eng (hindi to english)
dict-gcide
dictionaries-common
dict-jargon
dict-moby-thesaurus
dict-vera

After installing this (and other dictionaries of your choice) there is a small tweak we need to do to make the dictionary work offline

Go to Applications --> Office--> Dictionary and run the programme Dictionary

In the Open Application go to Edit --> preferences
In Source select ADD and
in description add any name you want to use for your customized dictionary services (replace source with a identifiable name)
Let transport be as it is (Dictionary Server)
change Hostname to 127.0.01 (replace dict.org)
Port - Leave as it is. enter add then in the Select a Dictionary Source for looking up words Select the Dictionary source your just added
Enter Close
Type any word to test if the dictonary works (you can / should test with your internet off)
If you get a meaning or any output means its working. Congratulations.

Ubuntu Tip:Awesome software-properties update for PPAs in Karmic

2009-10-12T23:26:00.000-07:00

* new helper script “add-apt-repository” that can be used to enable a repository from the commandline. Useful for e.g.’add-apt-repository ppa:gnome-desktop’

I gave it a try with `sudo add-apt-repository ppa:jpeddicord`. Not only did it add an entry to sources.list.d, it also fetched the GPG key automatically.

Out of curiosity, I opened software-properties-gtk (system > admin > software sources) and tried to add a PPA on the third-party software tab.

soft-prop-gtk-add-ppa

Using the same syntax for the add-apt-repository command, it worked. Didn’t appear to grab the GPG key at first, but after restarting the interface the key was indeed there.This is awesome, and definitely lowers the barrier for adding PPAs to a system.

Credit goes here

Reinstall Ubuntu Grub Bootloader After Windows Wipes it Out

2009-09-26T04:58:00.000-07:00

If you run a dual-boot system with Linux and Windows, this has happened to you. You had to do your monthly reinstall of Windows, and now you don’t see the linux bootloader anymore, so you can’t boot into Ubuntu or whatever flavor of linux you prefer.

Here’s the quick and easy way to re-enable Grub.

1) Boot off the LiveCD

2) Open a Terminal and type in the following commands, noting that the first command will put you into the grub “prompt”, and the next 3 commands will be executed there. Also note that hd0,0 implies the first hard drive and the first partition on that drive, which is where you probably installed grub to during installation. If not, then adjust accordingly.

sudo grub

> root (hd0,0)

> setup (hd0)

> exit

Reboot (removing the livecd), and your boot menu should be back.

Only read below if Windows is now missing from the boot menu

If you installed Ubuntu before you installed Windows, then Ubuntu will not have anything in the grub configuration for Windows. This is where you’ll have to do a bit of manual editing to the grub boot menu file.

If you open the file /boot/grub/menu.lst with the following command:

sudo gedit /boot/grub/menu.lst

You’ll see a sample section for Windows, which you’ll want to uncomment and add to the boot menu list in whatever position you want it in. (uncomment by removing the #’s)

# title Windows 95/98/NT/2000
# root (hd0,0)
# makeactive
# chainloader +1

Note that you should also verify that hd0,0 is the correct location for Windows. If you had installed Windows on the 4th partition on the drive, then you should change it to (hd0,3)

source Click here

Mark Shuttleworth Announces via video Ubuntu 10.04: Lucid Lynx

2009-09-24T21:50:00.000-07:00

Mark Shuttleworth spoke via video to UbuCon at the Atlanta Linux Fest 2009 and announced the name of the next Ubuntu release. Ubuntu 10.04 will be code named “Lucid Lynx” and will be an LTS release with support for the desktop for 3 years and for the server for 5 years.

How to let normal users shut down the computer in Linux

2009-09-08T04:53:00.000-07:00

This may seem like a stupid issue - why SHOULDN'T the average user be able to turn off his/her own machine?

The answer is that Linux is inherently designed as a multiuser system. It would generally be a bad thing if any one user would be allowed to spontaneously turn off the computer while other users are working. Just imagine what hell would ensue if your webserver were taken down by some insignificant user halfway across the world.

Of course, it does seem a little overprotective if the user is physically sitting at the machine, since he/she could just reach over and hit the power button (don't do that!!!).

There are several schools of thought concerning how to allow a user to shut down a machine properly. The first method seems somewhat useless to me, but I put it here for completeness.

shutdown.allow
There is a file in /etc called shutdown.allow (and if there isn't, root can add it). This file contains a list of users (1 per line) who are allowed to shutdown the computer.

This doesn't mean that these users can invoke the shutdown (or reboot or halt) command(s). Instead, it means that an authorized user can shut down the computer by pressing ctrl+alt+del.

In order for this to occur, the ctrl+alt+del key sequence must be trapped in the /etc/inittab file. The necessary line in inittab is

ca:12345:ctrlaltdel:/sbin/shutdown -t1 -a -r now

When ctrl+alt+del is pressed, init checks if there is an authorized user (listed in /etc/shutdown.allow) logged into any virtual console, and proceeds to shutdown if this is true.

Of course, if I'm running X windows, then generally the window manager will trap ctrl+alt+del for itself, so this won't work anymore.

sudo
The program sudo allows normal users to execute certain root-only commands. Which users are authorized to run which commands is specified in the /etc/sudoers file. This should only be edited with the command visudo.

For example, suppose I wanted to add a group of users who are allowed to shut down the machine. So I first want to add a group called "shutdown" (run these commands while root)

groupadd shutdown

Then I need to edit the /etc/group file to add users to the "shutdown" group. I just tack the usernames at the end of the shutdown line, separated by commas, e.g.

shutdown:x:407:user1,user2,...

Whatever users I put there will be able to shut down the computer (so choose wisely). Now I need to configure sudo to allow members of the "shutdown" group to actually invoke the assorted shutdown commands provided in linux. Run visudo and add the following lines

%shutdown ALL=(root) NOPASSWD: /sbin/reboot
%shutdown ALL=(root) NOPASSWD: /sbin/halt
%shutdown ALL=(root) NOPASSWD: /sbin/shutdown

This allows the "shutdown" group to run /sbin/reboot, /sbin/halt, and /sbin/shutdown AS IF THEY WERE ROOT. The only caveat is that the users must run the commands with the command sudo in front, e.g.

sudo /sbin/halt

This is always a bit of a pain (and users never remember), so I can create the following script called "/usr/bin/reboot" (and similar scripts for halt and shutdown)

#! /bin/sh
sudo /sbin/reboot $*

Remember to make these scripts executable! To make this slightly more secure, I might want to change the ownership of these scripts to the "shutdown" group

chgrp shutdown /usr/bin/reboot /usr/bin/halt /usr/bin/shutdown

and then make them executable only for the group "shutdown"

chmod g+x /usr/bin/reboot /usr/bin/halt /usr/bin/shutdown

KDE shutdown
If you are running kdm (the kde display manager - e.g. graphical login) then the shutdown behavior can be modified in "Control Panel" (in "Administrator Mode" of course). If you are starting KDE manually (using startx or startkde) then you will have to resort to the previous "sudo" solution (and probably add a shortcut on the desktop to one of those scripts).

XFCE4 shutdown
If you are using xfce4 then you will need to configure a few items in order to use the built-in "Reboot computer"/"Turn off computer" options available when you are logging out.

CHANGE - SEE BELOW FOR XFCE 4.2

XFCE 4.0
First, all users who are allowed to shut down the machine from xfce4 must be listed in the /etc/xfce4/shutdown.allow file (syntax is just like in the /etc/shutdown.allow file - see above). Second, the file permissions on the xfce4-shutdown program must be modified. This file is usually in /usr/sbin/xfce4-shutdown, so I would type

chmod u+s /usr/sbin/xfce4-shutdown

the "u+s" argument means that the command xfce4-shutdown will run as though the owner (probably root) initiated it, regardless of which user actually called the program.

This should be enough to shut down the computer from xfce4.

Instructions for XFCE 4.2 The game has changed for xfce 4.2. Now you must instead allow sudo access to a program called /usr/sbin/xfsm-shutdown-helper (note: this may also be located in /usr/local/libexec/ - just use the "locate" command to find xfsm-shutdown-helper).

Using the same kind of ideas presented above in the sudo method of shutdown, I add the following line to /etc/sudoers file (using visudo)

%shutdown ALL=(root) NOPASSWD: /usr/sbin/xfsm-shutdown-helper

This allows the "shutdown" group to shutdown the machine.

This page has been visited 20,481 (19 today) times since January 13, 2005

Source http://www.spencerstirling.com

Instant LAN File Sharing With Python

2009-09-07T00:09:00.000-07:00

The other day I was chatting with a co-worker and he pointed out a very simple command that could be used to quickly and easily share files with people within your LAN. This could also be used to share with people on the internets, but you’d have to configure NAT from your router. That much of the configuration is up to you, but I’ll share with you the quick ‘n easy webshare command.

The only requirement, as far as I can tell, is python. I’ve run it on my Linux machine as well as my OS X machine and it worked just fine with no other configuration or packages installed. It should likely work on anything else that has python installed as well.

To share the contents of any folder on your machine simply run:

python -c "import SimpleHTTPServer; SimpleHTTPServer.test();"

You can run that one-liner anywhere on your file system and then access the files via your browser. Simply point your browser to your LAN IP port 8000 and you should see an index listing of the files.

To make this a little simpler I made it an alias in my .bashrc file. Just add this line somewhere in your .bashrc or .bash_aliases:

alias webshare='python -c "import SimpleHTTPServer; SimpleHTTPServer.test();"'

At this point you can simply run the command webshare anywhere on your file system and share those files. This makes for a really simple tool for sharing files quickly and un-sharing them as soon as you’re done. Just hit ctrl-c to cancel and close the process.

source ubuntu-tutorials.com

Boot Time: Ubuntu 9.10 Alpha 4 vs. Windows 7 RC

2009-08-31T04:58:00.000-07:00

Using APT Offline

2009-08-22T05:00:00.000-07:00

Overview

APT being available on both machines gives the simplest configuration. The basic idea is to place a copy of the status file on the disc and use the remote machine to fetch the latest package files and decide which packages to download. The disk directory structure should look like:

/disc/
archives/
partial/
lists/
partial/
status
sources.list
apt.conf

The configuration file

The configuration file should tell APT to store its files on the disc and to use the configuration files on the disc as well. The sources.list should contain the proper sites that you wish to use from the remote machine, and the status file should be a copy of /var/lib/dpkg/status. Please note, if you are using a local archive you must use copy URIs, the syntax is identical to file URIs.

apt.conf must contain the necessary information to make APT use the disc:

APT
{
/* This is not necessary if the two machines are the same arch, it tells
the remote APT what architecture the Debian machine is */
Architecture "i386";

Get::Download-Only "true";
};

Dir
{
/* Use the disc for state information and redirect the status file from
the /var/lib/dpkg default */
State "/disc/";
State::status "status";

// Binary caches will be stored locally
Cache::archives "/disc/archives/";
Cache "/tmp/";

// Location of the source list.
Etc "/disc/";
};

More details can be seen by examining the apt.conf man page and the sample configuration file in /usr/doc/apt/examples/apt.conf.

On the remote Debian machine the first thing to do is mount the disc and copy /var/lib/dpkg/status to it. You will also need to create the directories outlined in the Overview, archives/partial/ and lists/partial/ Then take the disc to the remote machine and configure the sources.list. On the remote machine execute the following:

# export APT_CONFIG="/disc/apt.conf"
# apt-get update
[ APT fetches the package files ]
# apt-get dist-upgrade
[ APT fetches all the packages needed to upgrade your machine ]

The dist-upgrade command can be replaced with any-other standard APT commands, particularly dselect-upgrad. You can even use an APT front end such as dselect However this presents a problem in communicating your selections back to the local computer.

Now the disc contains all of the index files and archives needed to upgrade the Debian machine. Take the disc back and run:

# export APT_CONFIG="/disc/apt.conf"
# apt-get check
[ APT generates a local copy of the cache files ]
# apt-get --no-d -o dir::etc::status=/var/lib/dpkg/status dist-upgrade
[ Or any other APT command ]

It is necessary for proper function to re-specify the status file to be the local one. This is very important!

If you are using dselect you can do the very risky operation of copying disc/status to /var/lib/dpkg/status so that any selections you made on the remote machine are updated. I highly recommend that people only make selections on the local machine - but this may not always be possible. DO NOT copy the status file if dpkg or APT have been run in the mean time!!

Source www.fifi.org

setting up moin moin wiki

2009-08-19T01:21:00.000-07:00

Install Required Packages
Required packages are as follows:
python-moinmoin (Which should point to the proper python version)
apache2 webserver

sudo apt-get install python-moinmoin
sudo apt-get install apache2

Create a Wiki With "wikiname"
Create a wiki called "wikiname" and set the permissions.

cd /usr/share/moin
sudo mkdir wikiname
sudo cp -R data wikiname
sudo cp -R underlay wikiname
sudo cp server/moin.cgi wikiname
sudo chown -R www-data.www-data wikiname
sudo chmod -R ug+rwx wikiname
sudo chmod -R o-rwx wikiname

Configure MoinMoin to Locate "wikiname"
Relevant MoinMoin config files are located in /etc/moin/
Edit /etc/moin/farmconfig.py, and after the line "wikis = [" add your "wikiname". For a single instance wiki, this would entail renaming the following line from:

("mywiki", r".*"),

("wikiname", r".*"),

Copy the /etc/moin/mywiki.py file to /etc/moin/wikiname.py:

sudo cp /etc/moin/mywiki.py /etc/moin/wikiname.py

Edit the /etc/moin/wikiname.py and change all instances of mywiki to wikiname. In addition to this, change the data dir to point to your local installation of MoinMoin:

data_dir = '/usr/share/moin/wikiname/data'

Note :- You can simply copy the data directoy of old wiki to the above set folder to get the pages from the old pages to the newly installed wiki
Make apache ready for your wiki
Insert into /etc/apache2/sites-available/default (inside of the "" tag)

### moin
ScriptAlias /wikiname "/usr/share/moin/wikiname/moin.cgi"
alias /wiki "/usr/share/moin/htdocs"
alias /moin_static171 "/usr/share/moin/htdocs"

Order allow,deny
allow from all

### end moin

Restart apache to apply your changes:

sudo /etc/init.d/apache2 restart

See if it works
Go to your wiki's homepage:
http://127.0.0.1/wikiname Or try the test command:
http://127.0.0.1/wikiname?action=test
Security
You should probably set up PasswordProtectedEditing and investigate other security stuff: SecurityPolicy.
Troubleshootings
Server Name warning
apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1 for ServerName
http://wiki.apache.org/httpd/CouldNotDetermineServerNamehighlight=(ServerName)

Solution:
Add in /etc/apache2/apache.conf the following: ServerName
Where is your actual host name, like www.google.com or IP like 89.234.12.45

Use Mutt with Gmail

2009-08-18T04:50:00.002-07:00

================
Introduction
================

This page is a guide to using the email client Mutt to send, receive and read email under Ubuntu using a Gmail account as a relay. It has been tested and extensively used under Ubuntu Intrepid Ibex. There are a few steps involved but if followed carefully and in sequence you will soon be using Mutt successfully with your Gmail account.

In sequence we will:

1. Introduce John!
2. Introduce vim
3. Set up SSL
4. Set up msmtp
5. Set up Fetchmail
6. Set up Procmail
7. Set up Mutt

=====================
1. Introducing John ...
=====================

To avoid confusion in editing the many configuration files involved in this setup I will describe the setup of mutt and gmail for my new friend John, who has been borrowed from this guide's big brother. John's details are as follows:

Code:

Gmail Address: john.example@gmail.com
Gmail Password: rover
Computer Username: john

John's details will always be in italics, bold and in red to remind you, Gentle Reader, to substitute your details for his. Hopefully this will lessen the confusion that I have unintentionally created with older versions of this page!

Now to introduce one of my best friends: vim...

=====================
2. Introducing vim ...
=====================

I have been somewhat taken to task for throwing vim into this guide without too much warning, for which my apologies to all. vim is the text editor that I feel suits mutt the best but a little preparation is a good idea before launching straight into it. Download vim from the repository as follows:

Code:

sudo apt-get install vim

and once vim is installed run through the builtin tutorial by simply running:

Code:

vimtutor

It may take a little time to come to grips with this great editor but trust me it is time well spent. For those who find it all a little hard there is always nano or pico!

Now lets get started with SSL:

============
3. SSL Tools
============

Gmail uses the POP3-over-SSL protocol to protect the transmission of username and password over the Internet. You will need to install both open SSL and a certificate pack from the repository as follows:

Code:

$ sudo apt-get install openssl ca-certificates

Later you will need to add the necessary SSL instructions to Fetchmail, but the next step is to install the software to send mail from your computer to the server: ssmtp.

=========
4. msmtp
=========

msmtp is a great and wonderfully reliable way to move mail from your computer. Download it from the repository as follows:

Code:

$ sudo apt-get install msmtp

There is a single configuration file to be altered: $HOME/.msmtprc. It can be created and permissions set as follows:

Code:

$ touch $HOME/.msmtprc
$ touch $HOME/.msmtp.log
$ chmod 0600 $HOME/.msmtprc

Below is the required configuration for a Gmail server:

Code:

account default
host smtp.gmail.com
port 587
from john.example@gmail.com
tls on
tls_starttls on
tls_trust_file /etc/ssl/certs/ca-certificates.crt
auth on
user john.example
password rover
logfile ~/.msmtp.log

Now to setup Fetchmail:

============
5. Fetchmail
============

Fetchmail is great tool to download mail from Gmail. Download it from the repository as follows:

Code:

$ sudo apt-get install fetchmail

Once again a single configuration file is required and so you will need to create ~/.fetchmailrc as follows:

Code:

$ vim ~/.fetchmailrc

The following configuration allow Fetchmail to access and fetch email from Gmail, leave a copy of the mail on the Gmail server and pass the mail to Procmail on your local machine. The SSL configuration is included here as well:

Code:

poll pop.gmail.com
with proto POP3
user 'john.example@gmail.com'
there with password 'rover'
is 'john' here
mda "/usr/bin/procmail -d %T"
options
no keep
ssl
sslcertck
sslcertpath /etc/ssl/certs

All done except as a final touch, since the username and password are openly in this file,you will need to make the file readable only by the file owner. If this is not done Fetchmail will not even run:

Code:

$ chmod 600 ~/.fetchmailrc

Now would be a good to time to make sure you have POP forwarding enabled in your Gmail account. You will find this in: Settings - Forwarding and POP. Note also that Gmail has a little oddity in regard to the "keep" and "nokeep" command of Fetchmail. You cannot remove mail from Gmail servers via POP3 but you can choose to have your messages archived, kept or deleted once they have been downloaded via POP3. This is a Gmail setting hidden in Settings - Forwarding and POP: "When messages are accessed with POP...".

Now for the mail delivery program Procmail:

===========
6. Procmail
===========

Procmail is great sorting tool for use with any mail setup. It can be easily downloaded from the repository:

Code:

$ sudo apt-get install procmail

So where will Procmail deliver to? Traditionally all mail goes to the location specified in the $MAIL environment variable, but in a default Ubuntu system this is often not set. Set the MAIL variable by opening ~/.bashrc as follows:

Code:

$ vim ~/.bashrc

and adding the following, using your own username:

Code:

# Sets the Mail Environment Variable
MAIL=/var/spool/mail/john && export MAIL

A very simple configuration file must be created for procmail as follows:

Code:

$ vim ~/.procmailrc

and below is a very simple start to what can be quite a complex file:

Code:

# Environment variable assignments

PATH=/bin:/usr/bin:/usr/local/bin
VERBOSE=off # Turn on for verbose log
MAILDIR=$HOME/Mail # Where Procmail recipes deliver
LOGFILE=$HOME/.procmaillog # Keep a log for troubleshooting.
# Recipes
:0:
* ^TOmutt-user
mutt

I include a very simple sorting recipe with the file: this one intercepts everything addressed to "mutt-user" and directs it to $HOME/Mail/mutt. This is the mutt-user mailing list which I would advise all new mutt users to join. And lets not forget to create the Mail folder:

Code:

$ mkdir $HOME/Mail

Now finally to Mutt.

=======
7. Mutt
=======

Mutt is one of the truly great pieces of software under Linux. The following command downloads Mutt from the Ubuntu repository:

Code:

$ sudo apt-get install mutt

Mutt is driven by a configuration file that can be created as follows:

Code:

$ vim ~/.muttrc

I have spent some time building this file from scratch but for you, Gentle Reader, I include here a more basic version, similar to the one I started from:

Code:

#======================================================#
# Boring details
set realname = "john"
set from = "john.example@gmail.com"
set use_from = yes
set envelope_from ="yes"
set sendmail="/usr/bin/msmtp"

# If not set in environment variables:
set spoolfile = /var/spool/mail/john

#======================================================#
# Folders
set folder="~/Mail" # Mailboxes in here
set record="+sent" # where to store sent messages
set postponed="+postponed" # where to store draft messages
set move=no # Don't move mail from the spool.

#======================================================#
# Watch these mailboxes for new mail:
mailboxes ! +Fetchmail +slrn +mutt
set sort_browser=alpha # Sort mailboxes by alpha(bet)

#======================================================#
# Order of headers and what to show
hdr_order Date: From: User-Agent: X-Mailer \
To: Cc: Reply-To: Subject:
ignore *
unignore Date: From: User-Agent: X-Mailer \
To: Cc: Reply-To: Subject:

#======================================================#
# which editor do you want to use?
# vim of course!
set editor="vim -c 'set tw=70 et' '+/^$' "
set edit_headers # See the headers when editing

#======================================================#
# Aliases

set sort_alias=alias # sort aliases in alpha order by alias name

#======================================================#
# Colours: This scheme is fairly basic and only
# really works if your Terminal background is white

color hdrdefault black default
color quoted red default
color signature brightblack default
color indicator brightwhite red
color attachment black green
color error red default
color message blue default
color search brightwhite magenta
color status brightyellow blue
color tree red default
color normal blue default
color tilde green default
color bold brightyellow default
color markers red default

#======================================================#
# Odds and ends
set markers # mark wrapped lines of text in the pager with a +
set smart_wrap # Don't wrap mid-word
set pager_context=5 # Retain 5 lines of previous page when scrolling.
set status_on_top # Status bar on top.
push # Shows mutt version at startup

Note: Procmail will create your mailbox in the spool, and set the appropriate permissions, when it first receives mail from fetchmail so don't worry that mutt cannot initially find this mailbox. If you wish to create the mailbox yourself the following permissions and ownership are required (taken from my own system):

Code:

-rw-rw---- 1 andrew mail 0 2008-10-23 10:12 /var/spool/mail/andrew

And finally it is reward time as you open Mutt, type ! to open a shell prompt, type fetchmail -v and start reading your mail! My parting gift is a little macro that was written for me by a generous person on the mutt-user mailing list that will actually do this for you when you simply press the key "I". Place the following in your ~/.muttrc file:

Code:

macro index,pager I ' fetchmail -v'

And welcome to the world of mutt!

source : ubuntu-forums

Creating Custom Ubuntu Live-CD With Remastersys

2009-08-14T01:39:00.000-07:00

Remastersys is a tool that can be used to do 2 things with an existing Klikit or Ubuntu or derivative installation.It can make a full system backup including personal data to a live cd or dvd that you can use anywhere and install. It can make a distributable copy you can share with friends. This will not have any of your personal user data in it.

Install Remastersys in Ubuntu

The Remastersys repository needs to be added to your /etc/apt/sources.list

sudo vi /etc/apt/sources.list

Paste the following into the sources.list:

# Remastersys

deb http://www.remastersys.klikit-linux.com/repository remastersys/

Save and exit the file.

Update the source list using the following command

sudo apt-get update

Install remastersys using the following command

sudo apt-get install remastersys

This will complete the installation

Using Remastersys

In order to learn how you can use remastersys, run

sudo remastersys

remastersys Syntax

sudo remastersys backup|clean|dist [cdfs|iso] [filename.iso]

remastersys Examples

1) to make a livecd/dvd backup of your system

sudo remastersys backup

2) to make a livecd/dvd backup and call the iso custom.iso

sudo remastersys backup custom.iso

3) to clean up temporary files of remastersys

sudo remastersys clean

4) to make a distributable livecd/dvd of your system

sudo remastersys dist

5) to make a distributable livecd/dvd filesystem only

sudo remastersys dist cdfs

6) to make a distributable iso named custom.iso but only if the cdfs is already present

sudo remastersys dist iso custom.iso

cdfs and iso options should only be used if you wish to modify something on the cd before the iso is created. An example of this would be to modify the isolinux portion of the livecd/dvd

Creating An ISO Image

To create an iso image of your installation, simply run

sudo remastersys dist

This will create an iso image called customdist.iso in the /home/remastersys directory. The dist option makes that your personal folder (e.g. /home/ruchi) will not be included in the iso image. You might have to insert your Ubuntu installation CD during the process.

This is how the end of the process looks:

[...]
92.16% done, estimate finish Wed DEC 28 15:31:25 2007
93.39% done, estimate finish Wed DEC 28 15:31:25 2007
94.62% done, estimate finish Wed DEC 28 15:31:24 2007
95.85% done, estimate finish Wed DEC 28 15:31:24 2007
97.08% done, estimate finish Wed DEC 28 15:31:25 2007
98.31% done, estimate finish Wed DEC 28 15:31:25 2007
99.54% done, estimate finish Wed DEC 28 15:31:25 2007
Total translation table size: 2048
Total rockridge attributes bytes: 3950
Total directory bytes: 9094
Path table size(bytes): 54
Max brk space used 0
406890 extents written (794 MB)

/home/remastersys/customdist.iso is ready to be burned or tested in a virtual machine.

Check the size and if it is larger than 700MB you will need to burn it to a dvd

796M /home/remastersys/customdist.iso

Clean Up

After you’ve burnt the iso image onto a CD/DVD, you can run

sudo remastersys clean

to remove all temporary file created during the iso generation as well as the /home/remastersys directory.

also read: Click here

Did you know... ?

2009-08-12T22:30:00.000-07:00

Did you know...

A video about how quickly the technological development is happening. Interesting, but also kind of scary.

Ubuntu 9.10 is comming !!

2009-08-09T21:38:00.000-07:00

HOWTO Restore GRUB

2009-08-06T04:13:00.000-07:00

You have windows 98 and linux on the same hard disk and you choose GRUB as boot loader.At boot time you see a menu to choose windows or linux.
But one day you reinstall windows 98 and it rewrites your MBR and the menu has gone, now you only can boot windows.

What to do:
Put the redhat boot disk you created on the installation on the floppy drive, boot the system and run grub command

Remember that for grub (hd0,1) means hda (primary controller master), second partition.

Now we need to tell grub where are the grub files:

If you know where they are, type something like:

root (hd0,1)

else if you have no idea, type:

find /boot/grub/stage1

and then the root command with the correct parameters:

setup (hd0)

to install it on hd0, that is MBR of the first HD.

type quit and reboot.
The menu will appear again.
If you want to make some changes to the boot menu, you must edit the file: /boot/grub/menu.lst

A sample menu.lst file is this:

default=0
timeout=5
splashimage=(hd0,1)/boot/grub/splash.xpm.gz

title Red Hat Linux (2.4.18-14)
root (hd0,1)
kernel /boot/vmlinuz-2.4.18-14 ro root=LABEL=/ hdc=ide-scsi
initrd /boot/initrd-2.4.18-14.img
title Red Hat Linux (2.4.18-openmosix3)
root (hd0,1)
kernel /boot/vmlinuz-2.4.18-openmosix3 ro root=/dev/hda2 hdc=ide-scsi
initrd /boot/initrd-2.4.18-openmosix3.img
title WindowsME
rootnoverify (hd0,0)
chainloader +1

Playing windows games in linux

2009-07-29T02:14:00.000-07:00

Those who want to play windows games in Linux try click me

How do I logout Linux user?

2009-07-21T04:18:00.000-07:00

Q. How do I logout Linux user?

A. root or admin user can logout any user forcefully. If you are logged in as vivek and just wanted to logout or logoff, type logout command or hit

CTRL+D:
$ logout

You will be logout of a login shell session or secure shell session.
Task: Linux logout user

If you would like to logout other users, you must login as root user. Next you need to use pkill command.
pkill command syntax

pkill -KILL -u {username}

To see list of logged in user type who or w command:

# who
OR
# w

To logout user called raj, enter:

# pkill -KILL -u raj
OR
$ sudo pkill -KILL -u raj

For more information read our article - Howto: Linux kill and logout users

VideoLAN - VLC 1.0.0 has officially been released

2009-07-14T03:09:00.000-07:00

VLC media player - A universal media player which plays video and audio files of any known format has reached the version 1.0 milestone. I especially have a liking for this media player because it is available for Windows, Linux, Mac OS X, BeOS and BSDs. And, in my experience, I never ever had to hunt for media codecs once I installed VLC on my machine. Heck, it even plays Flash (.flv) video files.

Check it out

Recovering Ubuntu After Installing Windows

2009-07-13T03:50:00.000-07:00

There may be situation where we have to reinstall windows in a windows ubuntu dual boot system.
When you reinstall windows it will overwrite grub and ubuntu will disappear from the grub list.
In such case it is possible to recover the ubuntu grep boot loader back For more details follow the link

Tired of sudo asking for your password?

2009-07-12T22:13:00.000-07:00

Yes, I am.

I am tired of sudo asking for my password everytime I need to install a package with apt or aptitude. Someone could say this is the B-side of security, but not enough for me to justify it (and I’m the only user of this pc). So, even if someone could define this insane or unsafe, here there is a way to avoid that epic question.

DISCLAMER
Keep your eyes open ad your fingers ready, you can make a disaster if don’t.

Now that I’ve washed my hands, let’s keep going with the stuff. The configuration’s file we need to modify is /etc/sudoers , and no, we can’t do it with gedit/kate/nano… We need to use visudo, as written in the first line of that file. So we need to open a terminal and launch sudo visudo (and, obviously, insert the password when asked). Now scroll until the line:

# User privilege specification
root ALL=(ALL) ALL
elwood ALL=(ALL) ALL

and add a new line like this: you-user localhost = command you need . For me it’s as follow

elwood localhost = NOPASSWD: /usr/bin/aptitude /usr/bin/apt-get

Save and exit with ctrl+x and from next login sudo will stop prompting for the password. Other commands, if needed, can be addedd at the end of the line without writing a new rule. For other uses and more about setting this permissions just read man sudoers

Source: aarcudi.netsons.org

Songbird 1.2 Released

2009-07-10T06:14:00.000-07:00

Songbird is a Mozilla based good music player check it out
download

How to Erase CD-RW/DVD-RW

2009-07-08T00:53:00.001-07:00

If you want to Erase CD-RW/DVD-RW in Ubuntu use the one of the following options

Option 1

Open your terminal and run the following commands

umount /dev/cdrom

cdrecord dev=/dev/cdrom blank=fast

Option 2

Install brasero using the following command

sudo apt-get install brasero

After installation you need to go to Applications/Sound & Video/brasero.One of the options on the Disc menu is to erase the disk.

You can also use k3b.

Nice Ubuntu Themes for Jaunty and Intrepid users

2009-07-08T00:48:00.000-07:00

Some nice ubuntu themes for jaunty and intrepid users check it out here

Want to see Taj Mahal ???

2009-05-28T22:33:00.000-07:00

Taj Mahal Sunset No.01 in India

PostgreSQL 8.1 + phppgadmin on Debian mini-HOWTO

2009-05-19T21:47:00.000-07:00

Install required packages

aptget update
aptget install postgresql8.1 postgresqlclient8.1 postgresqldoc8.1 phppgadmin php5pgsql
libapache2modphp5

First test with PostgreSQL
Login pgsql console as user "postgres":

localhost:~# su
localhost:~# su postgres
postgres@localhost:~$ psql template1
Welcome to psql 8.1.9, the PostgreSQL interactive terminal.
Type: \copyright for distribution terms
\h for help with SQL commands
\? for help with psql commands
\g or terminate with semicolon to execute query
\q to quit
template1=#

Update pgsql user "postgres" password (required by phppgadmin):

template1=# ALTER USER postgres PASSWORD 'passwd';
ALTER ROLE
template1=# \q
postgres@localhost:~$

Create pgsql user "root" with database "AL32UTF8", with basic login:

Welcome to psql 8.1.9, the PostgreSQL interactive terminal.
Type: \copyright for distribution terms
\h for help with SQL commands
\? for help with psql commands
\g or terminate with semicolon to execute query
\q to quit
template1=# ALTER USER root PASSWORD 'passwd';
ALTER ROLE
template1=# \q
postgres@localhost:~$ psql AL32UTF8
Welcome to psql 8.1.9, the PostgreSQL interactive terminal.
Type: \copyright for distribution terms
\h for help with SQL commands
\? for help with psql commands
\g or terminate with semicolon to execute query
\q to quit
AL32UTF8=# \q
postgres@localhost:~$ exit
logout
localhost:~# psql AL32UTF8
Password:
Welcome to psql 8.1.9, the PostgreSQL interactive terminal.

Type: \copyright for distribution terms
\h for help with SQL commands
\? for help with psql commands
\g or terminate with semicolon to execute query
\q to quit
AL32UTF8=> \q
localhost:~#
localhost:~# su
localhost:~# su postgres
postgres@localhost:~$ createuser DRS root
CREATE ROLE
postgres@localhost:~$ createdb O root AL32UTF8
CREATE DATABASE
postgres@localhost:~$ psql template1

Configure and working with phppgadmin
Edit /etc/phppgadmin/config.inc.php, change the following line from:

$conf['extra_login_security'] = true;

into:

$conf['extra_login_security'] = false;

in order to allow root/postgres user login from phppgadmin.
Create symbolic link for phppgadmin web access:

localhost:~# ln s /usr/share/phppgadmin/var/www/

Access http://localhost/phppgadmin, login as root or postgres, enjoy your newly installed
PostgreSQL server :)

Extract File(s) From ISO Under Linux OS

2009-05-13T05:50:00.000-07:00

Let us assume that your ISO image name is disk1.iso.
Step # 1: First you need to create a directory /mnt/iso

# mkdir /mnt/iso
# mount -o loop disk1.iso /mnt/iso

Step # 2: Extract file
Now you can easily copy file called file.txt from iso disk image to /tmp directory :

# cd /mnt/iso
# cp file.txt /tmp

Step # 3: Copy foo.rpm from ISO disk image:

# cd /mnt/iso/RedHat/RPMS
# cp foo.rpm /tmp

How to Configure BSNL EVDO USB BroadBand in Linux

2009-05-13T05:46:00.000-07:00

Configuring the BSNL Evdo USB Broadband in linux is very much similar to configuring any USB modem in Linux. 3 steps are involved.

1.Detecting the device
2.Configuring wvdial.conf
3.Dialling

In most cases the hardware is auto detected and drivers are automatically loaded. You can check your /dev/ directory for any of these files.
ttyusb0, ttyusb1, ttyusb2 ……
After plugging in he modem, a new device should appear. In most cases it ttyusb0. If no file is appearing then you will have to manually load the drivers by issuing the following command.
modprobe usbserial vendor=0×05c6 product=0×6000
This will load the drivers and make your new device visible in /dev/
Now add the following lines to your wvdial.conf

[Dialer Defaults]
Modem=/dev/ttyUSB0
Baud=115200
Dial Command = ATDT
Baud=115200
Dial Command = ATDT
init1=ATZ
init2=AT+CRM=1
Flow Control= Hardware (CRTSCTS)
Username =
Password =
Phone = #777
Stupid Mode = 1

Now try the command wvdial in your terminal. It should work.

Some Video Conversions

2009-05-13T05:39:00.000-07:00

ffmpeg is an excellent application on video conversion. It supports most of the file formats.

ffmpeg [[infile options][-i infile]]… {[outfile options] outfile}…

Convert from MPG to 3GP
ffmpeg -i video_clip.mpg -s qcif -vcodec h263 -acodec mp3 -ac 1 -ar 8000 -ab 32 -y clip.3gp

ffmpeg -i inputfile.mpg -s qcif -vcodec h263 -acodec aac -ac 1 -ar 8000 -r 25 -ab 32 -y outputfile.3gp

Convert from AVI to 3GP
ffmpeg -i video_clip.avi-s qcif -vcodec h263 -acodec mp3 -ac 1 -ar 8000 -r 25 -ab 32 -y clip.3gp

ffmpeg -i inputfile.avi -s qcif -vcodec h263 -acodec aac -ac 1 -ar 8000 -r 25 -ab 32 -y outputfile.3gp

Convert from 3GP to AVI
ffmpeg -i clip.3gp -f avi -vcodec xvid -acodec mp3 -ar 22050 file.avi

you need to install the codecs previously. All the xvid,mp3,avi,3gp codecs can be updated very easily in the debian based distros. All other disros also having the codecs in their own repositories.

There are other media conversion utilities also there as mencoder,transcode and there are a lot of GUI tools for this like drip, k9copy etc.

flv to mp3

ffmpeg -i jaiho.flv jaiho.mp3

Recover root password under linux with single user mode

2009-05-13T05:32:00.000-07:00

It happens sometime that you can't remember root password. On Linux, recovering root password can be done by booting Linux under a specific mode: single user mode.
This tutorial will show how to boot Linux in single user mode when using GRUB and finally how to change root password.
During normal usage, a Linux OS runs under runlevels between 2 and 5 which corresponds to various multi-user modes. Booting Linux under runlevel 1 will allow one to enter into a specific mode, single user mode. Under such a level, you directly get a root prompt. From there, changing root password is a piece of cake.

1. Entering runlevel 1

Some Linux distribution, such as Ubuntu for instance, offer a specific boot menu entry where it is stated "Recovery Mode" or "Single-User Mode". If this is your case, selecting this menu entry will boot your machine into single user mode, you can carry on with the next part. If not, you might want to read this part.
Using GRUB, you can manually edit the proposed menu entry at boot time. To do so, when GRUB is presenting the menu list (you might need to press ESC first), follow those instructions:
use the arrows to select the boot entry you want to modify.
press e to edit the entry
use the arrows to go to kernel line
press e to edit this entry
at the end of the line add the word single
press ESC to go back to the parent menu
press b to boot this kernel
The kernel should be booting as usual (except for the graphical splash screen you might be used to), and you will finally get a root prompt (sh#).
Here we are, we have gained root access to the filesystem, let's finally change the password.

2. Changing root password

As root, changing password does not ask for your old password, therefore running the command:
# passwd
will prompt you for your new password and will ask you to confirm it to make sure there is no typo.
That's it, you can now reboot your box and gain root access again

How to replicate the installed packages of one system on another

2009-05-13T05:30:00.000-07:00

existing system:

sudo dpkg --get-selections > /someplacelikeafloppy/selections

new system:

sudo dpkg --set-selections < /someplacelikeafloppy/selections
sudo apt-get dselect-upgrade

The "selections" file is a plain text file, and can be edited to customize list of packages to install.

Adding a Local directory of deb packages as repository

2009-05-13T05:17:00.000-07:00

There may be situation like, you have a directory full of packages that you want to install. How will you do that. Here is an easy way to add your directory with packages to your source list and directly install packages using synaptic or apt-get what ever you like

please go through the below listing to know how to do it.

cd /storage #assume that your directory is named storage
dpkg-scanpackages . /dev/null > Packages

note the "." and the capital P

then add

deb file://storage ./

to your apt sources.list file
apt-get update

apt-get install whatever...

Adding ISO files to the APT sources file

2009-05-11T04:00:00.000-07:00

When it comes to collecting Debian packages into a transportable CD, nothing beats APTonCD for speed and convenience. However, do we always have to burn the the resulting ISO file to CD in order to use it on another machine? Is it possible to work with the ISO file directly? It is!

The first step is to mount the ISO file to a directory.

sudo mount -t iso9660 aptoncd-20081209.iso /home/username/apt -o loop

Then add the file to the repository list, simply modify /etc/apt/sources.list. Add the following line:

deb file:/home/username/apt/ /

From here on, we have access to the transferred packages. They will be available in all APT tools, including Synaptic.