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How install a Firewall on Linux and block IP's that bruteforce your system

Whenever I setup a Linux VPS, the first thing I do is install a firewall. I have noticed an increase in attacks on my servers, especially from China. I use
Config Server Firewall (CFG) and Login Failure deamon (LFD) because they are easy to set up and provide additional features like suspicious file reporting and system monitoring.

http://techarena51.com/index.php/how-to-configure-and-install-config-server-firewall-login-failure-daemon/

 

OK335xS Single board computer with two Ethernet Ports based on TI Sitara AM335x

Forlinx Embedded Technology Co.,Ltd (www.forlinx.net)is a global provider of ARM series single board computer.All products rangs from ARM9,ARM11,Cortex-A8 to Cortex-A9 platform.

OK335xS single board computer is one of  SDK board based on TI AM335x processor. after it is been launched, it has attracted many eyes from engineers all over the world.If you also have interests in it, please carefully check following contents for your reference.

OK335xS single board computer is a Cortex-A8 board based on TI AM3354 processor.It designs in the structure of CPU module(FET335xS)+ base board, and is used for commercial application(Temp range:-20℃~+70℃).and it support WinCE,Linux,Android/Starterware OS.

FET335xS CPU module is a high performance and cost effective module.It is designed as a  6-layer PCB board with the dimension of 42mm*52mm,and is with stamp hole interface.It integrates with 512M DDR3 RAM, and 256M SLC Nandflash for memory and support Ethernet,USB,UART,etc for connectivity.

and as for the base board, it measures 130mm*190mm and also support Ethernet, USB,CAN,485 bus function.Most importantly, OK335xS is the board with twoEthernet ports,which is a rare board based on Cortex-A8 platform.

335xS-1.jpg335xS-2.jpg

20140110012004_16852.jpg

 

The board  hardware resource are as follows:

FET335xS CPU Module Features

Key Parameters

CPU Processor: TI AM335X Cortex-A8

Main frequency: 800MHz

CPU Architecture Cortex-A8
RAM 512M DDR3
FLASH 256M SLC NandFlash
Operating Temperature -20℃~+70℃
Dimension 5.2cm*4.2cm
PMU TPS65217C
Voltage 5V
Humidity 10%~90%
OS Android2.3/4.2, Linux3.2, WinCE7.0
Pre-installed System Linux3.2
Graphics Processor Power VR SGX530

Function

USB 2.0 1x USB 2.0 HOST, 1x USB 2.0 OTG
Ethernet Dual Gigabit Ethernet
SD/MMC/SDIO 3x MMC
IIC 3x IIC
SPI 2x SPI
UART / IrDA 6x UART
GPIOs More than 20
ADC 8x ADC
Video Decoder Software codec
2D / 3D Support
Audio interface IIS interface port
JTAG Support
E2PROM Support (Used for encryption)

OK335xS Base Board Features

  SPI

1x SPI

  Power Supply

5V

  LED

1x LED

  LCD

Touch panel: support both resistive and capacitive;

Screen size: 4.3'', 5'', 7'', 8'', 10.4'' ;

Module: Support LCD to VGA module, LCD to LVDS module

  SD card slot

1x SD card slot

  WIFI

USB WiFi

  Serial Port

3x serial port

USB Device

1x USB 2.0

RTC

Support

  RS485

1x RS485, Multiplexed with profibus

  A/D

5x A/D

  IIC

1x IIC

  User Key

5x user key

Audio

3x Audio(1 for Phone, 1 for MIC, 1 for Linein)

  Boot Switch

Set to boot from SD card or NAND Flash

  Reset

Support

USB Host

4x USB 2.0 Host

  Ethernet

2x Gigabit Ethernet

  CAN

1x CAN

PWM

2x PWM( 1x backlight, 1x buzzer)

What's more, custom service based on TI AM335x is also provided.

If you hope to know the quotation and other details, please directly contact  This e-mail address is being protected from spambots. You need JavaScript enabled to view it .Thx.

 

4 Cutting Edge Web Browsers


This article highlights interesting open source web browsers that are in a very early stage of development. They have very different target audiences. Fifth is based on the WebKitFLTK web library, and seeks to retain the best features of Opera, but add a new few features. Dooscape uses the QtWebKit as its engine, and offers an intuitive interface. The latest major release of Emacs includes a built-in web browser, eww. The final web browser featured in this article is also distinct. Breach is a modular browser written entirely in Javascript. All four web browsers are released under an open source license.

<A HREF="http://www.linuxlinks.com/article/20141127141517421/NewWebBrowsers.html">Full article</A>

 

Linux Mint 17.1 Cinnamon Officially Released

Codenamed “Rebecca”, the Linux Mint 17.1 Cinnamon edition has been released, and brings many new improvements, featuring a brand new, more stable and polished Cinnamon then ever, a Ubuntu 14.04 software base and Linux Kernel 3.13.

 

Full article

 

A simple and easy way to install and configure puppet on Linux

Puppet is an automation tool which allows you to automate the configuration of software like apache and nginx across multiple servers.

Puppet installation
In this tutorial we will be installing Puppet in the Puppet/Agent mode.You can install it in a Stand Alone mode as well.

OS & software Versions
Centos 6.5
Linux kernel 2.6.32
Puppet 3.6.2

Let’s get to it then.

 

 

 

http://techarena51.com/index.php/a-simple-way-to-install-and-configure-a-puppet-server-on-linux/

 

Battle for Wesnoth 1.12 Has Big New Features [Overview, What’s New, Screenshots]

Battle for Wesnoth is one of the flagship open-source games, with a huge, dedicated community and an almost unmatched feature-completeness among the open-source games.

 

Full article

 

War Thunder Free Steam MMO Now with Linux Client

War Thunder, a free, popular MMO based on World War II, has received a Linux client, so you can now install and play War Thunder for free on Steam.

 

Full article

 

12 Awesome Themes for Mint 17.1 Cinnamon

With Mint 17.1 Rebecca being days away from release, and Cinnamon 2.4 looking so good, here is an overview of some of the best looking themes which allow you to beautify your desktop.

 

Full article

 

Cpu Replacement. Help

Hello guys,

I was wondering if i can replace my current CPU for a better CPU? Do i have to tweak anything in the BIOS or anywhere else in my system. Provided that both CPU require the same Socket which is compatible with my Motherboard's socket. So do i just physically take out the old CPU and install the other one in its place, and everything will boot normally?

Thanks.

 

Univention Corporate Server 4.0 released

This major release includes many new features. For example:

  • complete redesign of the Univention Management Console
  • virtualization of OpenStack and Amazon EC2 environments
  • based on Debian GNU/Linux 7.7 (Wheezy)
  • centralised management functions for the App Center
  • simplified installation process via Debian installer and web-based system configuration
  • performance boost of the OpenLDAP directory (mdb as storage backend by default)
  • support of UEFI SecureBoot for installation processes

Release notes at: http://docs.univention.de/release-notes-4.0-0-en.html

 

 

Scripting made fun: Creating a melody of simplicity

Last time I uncovered a language that created a two-way communication tunnel with my Linux system. When you learn a two-way method of communication, the intentions of both communicators are understood. My Linux systems understand my intentions. It knows that my objective is to make my system very simple to operate in accordance to my standard of simplicity. This way I can understand more thoroughly how my system works. Once approved, more of the underlining functions of my system are revealed. What I started creating was a melody of simplicity.

Last time, I wrote a blog titled “scripting made fun”. The article was to inspire a new way of scripting that removed boredom and fear of learning programming. When you enjoy what you are doing, you do more of it and differently. I found my unique communication style.

My system must be psychic; a voice repeatedly recited, “take a sentence of mundane commands and reduce them to one word”. I did this using variables. From variables now moving to actually writing scripts with multiple lines of code. For assistance, you can learn how scripts work by reading script files like “fstab” or “init.d”. Take time to dissect them. When learning Linux, allow yourself time to take things apart.

I kept the scripts in my home folder, and modified the default search path. This time, they have been placed in one of the already declared default search folders. As I furthered my readings of The LPI Linux essentials study material, It was recommended to place compiled or custom made programs in the “/usr/local/ directory”. I don't have to worry about my scripts being moved when my system upgrades.

When I placed the scripts in this directory, the owner changed from me to “root”. Give me back what is rightfully mine. I am not running “sudo” before my OWN programs. Management is under revision.

The command “chown” changes the ownership of a program. 

#sudo chown <new profile name> <name of file or diretory> 

Your files, directories, or scripts will have your profile name as the owner. That means, no sudo (HA!) 

These are the scripts in prototype form.

  1. endsystem

  2. opendvd

  3. playdvd

  4. systemrestart

  5. update_debian

Most of them are of basic “command and argument” format, “do this on/to this”. Simple? Perhaps. But something happened. I took it a step further. I am now using the if-then-else statements. Rather than just following orders, you follow orders based on logical conditions. Lets look at the “playdvd” script as an example.

 

Playdvd

 

#!/bin/bash

#This script will run vlc on DVD drive mounted in the /media folder as cdrom0

#If not, it will run vlc on dvd device /dev/sr0

if

[ -d /media/cdrom0 ]

then

vlc /media/cdrom0;

else

vlc /dev/sr0;

fi

#end

 

The if-then-else programming statements simply mean, if a condition is satisfied, execute a command on that condition, otherwise run the alternative if the condition is not.

 

“if

[ -d /media/cdrom0 ]

then

vlc /media/cdrom0;”

 

This statement means “if the directory '/media/cdrom0' exists, then run 'vlc' on that directory. The “-d” switch represents a directory as I have come to understand. In fact, if you were to run, “#ls -al” on the “/usr” directory, you would see that same “d” switch in the output attributes of a directory.

 

ls -al

total 132

drwxr-xr-x 10 root root 4096 Jun 23 10:09 .

drwxr-xr-x 22 root root 4096 Aug 31 22:51 ..

drwxr-xr-x 2 root root 65536 Nov 8 08:52 bin

drwxr-xr-x 2 root root 4096 Jun 23 10:22 games

drwxr-xr-x 18 root root 4096 Jun 23 10:24 include

drwxr-xr-x 163 root root 20480 Nov 8 08:52 lib

drwxr-xr-x 10 root root 4096 Jun 23 10:09 local

drwxr-xr-x 2 root root 12288 Oct 27 14:47 sbin

drwxr-xr-x 277 root root 12288 Nov 8 08:52 share

drwxr-xr-x 6 root root 4096 Oct 21 14:23 src

 

If you look at the line ending with “games”, you will notice that it begins with a “d”. This “d” label means “directory”. Going back to the [ -d /media/cdrom0 ] code line, what we are saying, if you find the directory “-d” of “/media/cdrom0”, then run “vlc /media/cdrom0”.

The “then” statement tells the script what to do after the first condition has been met.

“then

vlc /media/cdrom0”

The program looks for a directory named, “/media/cdrom0”. My dvd drive mounts itself in this directory whenever I insert a DVD or audio CD.

If for some reason, the directory “/media/cdrom0” does not exist, then the script must an. Alternative. “/dev/sr0” is the actual DVD/CD-ROM device. This line tells the script to run vlc on this directory if the first condition is not met.

“else

vlc /dev/sr0;”

fi

#end

You must also end a conditional script with an “fi” which means “end if”, otherwise the program won't know when to quite.

For every script created, it must be made executable, meaning it has to look like something the shell has to run not read. The command “chmod” does just that. The “chmod” command tells the shell what type of file permissions to give a user or group. There are three types, execute, read and write. Well, I wanted to give myself execute permissions on this script. The shell then allows me to run the script as a program.

#sudo chmod u+x playdvd = “u” means “the user, “x” means execute. The “+” means add the permission.

This command tells the shell to make the “playdvd” file an execution program. When the shell reads the commands “playdvd” it will execute all the lines in the file and perform the action.

Me and my mouse need consulting. I am spending way too much time on the terminal than on the point-and-click device. Can't help it. All I have to do is press a three-key combination, terminal opens, and I type my desired program. I even stopped physically opening up the dvd drive. I type a command to do that, and a command to close it.

Looking at it from another perspective. I am learning how to operate my system with or without the mouse.

 
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