Linux: 25 Iptables Netfilter Firewall Examples For New SysAdmins

Posted on in Categories Iptables, Linux, Linux distribution, Linux Embedded devices, Linux laptop last updated August 23, 2017

Linux comes with a host based firewall called Netfilter. The netfilter is a set of hooks inside the Linux kernel that allows kernel modules to register callback functions with the network stack. A registered callback function is then called back for every packet that traverses the respective hook within the network stack. This Linux based firewall is controlled by the program called iptables to handles filtering for IPv4, and ip6tables handles filtering for IPv6. I strongly recommend that you first read our quick tutorial that explains how to configure a host-based firewall called Netfilter (iptables) under CentOS / RHEL / Fedora / Redhat Enterprise Linux. If you are using Ubuntu/Debian Linux, see how to setup UFW for more info. This post lists most simple iptables solutions required by a new Linux user to secure his or her Linux operating system from intruders.

How To: Build an Embedded Linux Distribution From Scratch

Posted on in Categories GNU/Open source, Hardware, Linux, Linux distribution, Linux Embedded devices, Ubuntu Linux last updated August 16, 2008

Embedded Linux is the use of a Linux operating system in an embedded computer systems such as a mobile phones, personal digital assistants, media players etc. This tutorial shows you how to install Linux on a target system. Not a prebuilt Linux distribution, but your own, built from scratch.

Linux / UNIX minicom Serial Communication Program

Posted on in Categories Hardware, Howto, Linux, Linux Embedded devices, Tips last updated February 5, 2008

Linux comes with many serial text and gui based serial communication programs. My favorite is minicom – friendly menu driven serial communication program.

If you are addicted to DOS / Windows TELIX (a telecommunications program originally written for DOS and was released in 1986), minicom is for you under Linux / UNIX.

minicom Common features / usage

=> Setting up a remote serial console
=> Access a computer / server if the LAN is down
=> Connect to embedded Linux / BSD device via null modem cable
=> Connect to Cisco routers for configuration
=> Connect to dump device i.e. device w/o keyboard and mouse
=> Dialing directory with auto-redial
=> Support for UUCP-style lock files on serial devices
=> Separate script language interpreter
=> Capture to file
=> Multiple users with individual configurations

Let us see how to configure minicom for my Soekris net4801 Single Board Computer / embedded Linux device.
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Tutorial: Ubuntu Linux on a Handheld / Mobile Device

Posted on in Categories Hardware, Linux, Linux distribution, Linux Embedded devices, Ubuntu Linux last updated January 31, 2008

Ubuntu Linux is a great server and desktop distribution for x86 computers, but did you know that it’s also ideal for handheld and mobile embedded devices?

Ubuntu’s latest release, Gutsy Gibbon, now includes support for the embedded and mobile spaces with the Ubuntu Mobile and Embedded (UME) project. Get to know the UME project, and find out how to get started. The primary objective of this tutorial is to get you quickly acquainted with the Ubuntu embedded framework and tools. Along the way, you learn about several tools and new approaches to Linux kernel configuration and environment construction. You also learn about some other projects with goals similar to the UME project.

Topics

  • Introduction to the Ubuntu Mobile and Embedded (UME) project, its architecture, and its use
  • How to install and test the Hildon desktop
  • How to build a development environment for a mobile device
  • Other mobile platforms

=> Explore Ubuntu Mobile and Embedded [ free registration required ]