Video: Who Writes Linux Kernel?

last updated in Categories Linux

Linux kernel is the most prominent examples of free and open source software. The Linux kernel has received contributions from thousands of programmers and companies around the world. This professional video from the Linux foundation provides a quick insight into Linux building procedure. This is a powerful and inspiring story of how Linux has become a volunteer-driven phenomenon.

Download of the day: Linux kernel 2.6.24

last updated in Categories Download of the day, Linux

The Linux kernel version 2.6.24 has been released and available for download. From the announcement:

The release is out there (both git trees and as tarballs/patches), and for the next week many kernel developers will be at (or flying into/out of) LCA in Melbourne, so let’s hope it’s a good one. Nothing earth-shattering happened since -rc8, although the new set of ACPI blacklist entries and some network driver updates makes the diffstat show that there was more than the random sprinkling of one-liners all over the tree.

Download Linux kernel 2.6.24

=> Visit official kernel website to grab latest version. You may find our kernel compiling instructions useful.

Linux command to gathers up information about a Linux system

last updated in Categories CentOS, Debian Linux, Gentoo Linux, Howto, Linux, Networking, RedHat/Fedora Linux, Sys admin, Tips, Ubuntu Linux

If you are developing an application for Linux desktop and would like to automatically find out more information about system, use the following commands in shell scripts to gather information about system. Recently I was involved in project where I need to collect information about running GUI, browser and other information such as disk space, running kernel etc.

Find out KDE Desktop version:

konqueror --version

Find out Gnome Desktop version:

gnome-panel --version

Find out Mozilla browser version:

mozilla --version

Find out Firefox browser version:

firefox --version

Find out current Language:

set | egrep '^(LANG|LC_)'

Find out disk space usage:

df -h

Find/Estimate file space usage:

du -h

Find out version of Linux glibc:

ls -l /lib/libc-*.so /lib/libc.so*

Find out user limits:

ulimit -a

Find out installed device drivers (modules)

lsmod

Find out information about an X server:

xdpyinfo

It can find out:

  • Name of display:
  • Version number
  • Vendor name (such as The XFree86 Project)
  • Vendor release number
  • And XFree86 version number

Find out information about Linux CPU

cat /proc/cpuinfo

Find out information about Linux Memory

cat /proc/meminfo

OR

free -m

OR

free -g

Find out user shell name:

ps -p $$ | tail -1 | awk '{ print $4 }'

Dump Linux kernel variables

/sbin/sysctl -a

Find out running Linux kernel version:

uname -mrs
uname -a
cat /proc/version

Dump or display memory information and swap information:

free -m

Network card and IP address information:

ifconfig -a
ifconfig -a|less

Debian / Ubuntu Linux network configuration file (all interface eth0,eth1,…ethN)

more /etc/network/interfaces

Redhat / CentOS / Fedora Linux network configuration file (eth0)

more  /etc/sysconfig/network-scripts/ifcfg-eth0

Note replace eth1 for 2nd network card and so on.

Display routing information

route -n
route

Display list of all open ports

netstat -tulpn

View login related logs

tail -f /var/log/secure
vi /var/log/secure
grep 'something' /var/log/secure

View mail server related logs

tail -f /var/log/maillog
vi /var/log/maillog
grep 'something' /var/log/maillog

Find how long the system has been running

uname
w

Show who is logged on and what they are doing

w
who

Display list of tasks

top

Display all running process

ps aux
ps aux | grep process-name

Display list of all installed software on Redhat / CentOS / Fedora

rpm -qa
rpm -qa | grep 'software-name'
rpm -qa | less

Display list of all installed software on Debian / Ubuntu

dpkg --list

Once information collected it can be easily send as an email to help desk. You can use all above command to gathers information about a remote Linux system over secure ssh session (see related functions that gathers up information about a Linux and FreeBSD system). Best part is all above commands runs in non privileged mode.

How to compile and install Linux Kernel 4.18.10 from source code

last updated in Categories CentOS, Debian Linux, GNU/Open source, Howto, Linux

Compiling a custom kernel has its advantages and disadvantages. However, new Linux user/admin find it difficult to compile Linux kernel. Compiling kernel needs to understand few things and then type a couple of commands. This step by step howto covers compiling Linux kernel version 4.18.xx under an Ubuntu or Debian Linux. The following instructions successfully tested on an RHEL 7/CentOS 7 (and clones), Debian Linux, Ubuntu Linux and Fedora Linux 28. However, instructions remain the same for any other Linux distribution.