linux concepts

1. Differences(Linux)

2. Centos vs Ububtu
• The main difference is that CentOS is based on Redhat
Enterprise Linux, while Ubuntu/Ubuntu Server has its roots
in Debian.
• One philosophical difference that no administrator on an
Ubuntu system knows the root password (it's randomly
generated), and root-privileges are granted through the
'sudo' command.
• CentOS uses the YUM package manager with RPM
packages, while Ubuntu uses apt with DEB packages.
• Ubuntu tends to be less conservative than CentOS, which
means that its repositories contain fresher packages,
whereas CentOS packages are tend to focus on security
patches only.

3. Ubuntu vs Debain
• Ubuntu and Debian are closely related. Debian and Ubuntu are free
Linux distributions using the apt package management system.
• Ubuntu builds on the foundations of Debian's architecture and
infrastructure, but has a different community and release process.
• Ubuntu and Debian are distinct but parallel and closely linked
systems. The Ubuntu project seeks to complement the Debian
project .
• Ubuntu provides a system based on Debian with frequent, regular
releases and a consistent desktop interface. It is backed by
Canonical's commercial services and support on both the desktop
and the server. It releases critical bug fixes and is never more than
six months away from the latest version of anything in the open-
source world.

4. Red Hat vs Debain
Task RedHat Debian
Version /etc/redhat-release /etc/debian_release
Package GUI KPackageKit, yumex Synaptic Package Manager
Package management rpm, yum, yumex(GUI) dpkg, apt-*, aptitute
List packages rpm -qa dpkg -l
Which package a file
belong to?
rpm -qf filepath dpkg -S filepath
Package installation from
an available package file
rpm -ivh packagefile.rpm dpkg -i packagefile.deb
Remove package rpm -e packagename dpkg -r packagename
Package Search yum search ssh aptitude search ssh
Package installation yum install openssh aptitude install openssh
Package Removal yum remove openssh aptitude remove openssh
Interface configuration
/etc/sysconfig/network-
scripts/*
/etc/network/interfaces

5. Red Hat vs Debain
Task RedHat Debian
Network service /etc/init.d/network restart
/etc/init.d/networking
restart
Service Start/stop
service servicename
start,stop,restart
invoke-rc.d servicename
start,stop,restart
Service add/remove chkconfig update-rc.d
Apache Configuration /etc/httpd/* /etc/apache2/*
Apache Log files /var/log/httpd/* /var/log/apache2/*
Apache Default Document
Root
/var/www/html /var/www/www-data
xinetd /etc/xinetd.d/* /etc/inetd.conf
xinetd service xinetd restart update-inetd (options)
DNS config file /etc/named.conf /etc/bind/named.conf
DNS service file /etc/init.d/named /etc/init.d/bind9