Sometimes you feel it is necessary or to be handy to have a local yum server in your network.So let’s try to create a local yum server in your network.

Linux server configuration file checking commands in brief.These commands are useful for verifying configuration files in Linux server before applying to the server.

Steps: #yum install exim system-switch-mail After successful installation, we need to make some necessary configurations. Switch default MTA(Mail Transfer agent) to exim if it is sendmail or any other application by using system-switch-mail. Then stop sendmail service if it is running and disable in startup. #service sendmail stop #chkconfig  sendmail off And start exim service [...]

Building a centralized log host in your network will ease the process of troubleshooting your servers from a single window.Centralized log host will accepts all the log messages from client and store in that server.

virtusertable is used to do aliases to virtual domains hosted on the same server. In this case we use  mail1.domain.org as main host and mail2.domain.org as virtual host. Before creating virtusertable mapping ,you need to create a file virtusertable in /etc/mail/.In virtusertable each entry should be a single line.The entry in left hand side denotes [...]

Fencing is the disconnection of a node from the cluster’s shared storage. Fencing cuts off I/O from shared storage, thus ensuring data integrity. There are two fencing programs fenced Configured with CMAN/DLM GULM Configured with GULM servers When the cluster manager determines that a node has failed, it communicates to other cluster-infrastructure components that the [...]

Asterisk is a software implementation of a telephone private branch exchange (PBX) originally created in 1999 by Mark Spencer of Digium. Like any PBX, it allows attached telephones  to make calls to one another, and to connect to other telephone services including the public switched telephone network (PSTN) and Voice over Internet Protocol (VoIP) services. [...]

WebDAV stands for web based Distributed Authoring and Versioning.And it is a set of extension to the http protocol that allows users to directly edit files on the apache server so that they do not need to be downloaded/uploaded via FTP.apache Enabling WebDAV on apache web server includes the following steps Install mod_dav module Edit [...]

Creating user and group for mysqlmysql #groupadd mysql #useradd -g mysql mysql Get source from http://dev.mysql.com/downloads/mysql/5.0.html#source Unpack the package using the following command #tar -xvf mysql-5.x.x.tar.gz #cd mysql-5.x.x #./configure –prefix=/usr/local/mysql-5.x.x Then compile & install #make #make install Then create a symbolic link ‘mysql’ pointing to mysql-5.x.x(Installation directory) #ln -s /usr/local/mysql-5.0.37/ /usr/local/mysql  (Generally mysql installation path [...]

Get the source from http://www.php.net/download.php (php-5.x.x.tar.gz) Prerequisites Apache webserver Mysql Installation Goto the directory use this command to unpack the file tar -xvf php-5.x.x.tar.gz cd php-5.x.x ./configure –prefix=/usr/local/php –with-apxs2=/usr/local/apache2/bin/apxs –with-mysql=/usr/local/mysql * –prefix specifies the location where PHP is to be installed . * –with-apxs2 pointing to bin/apxs in the apache installation directory. * –with-mysql to [...]

RT-Linux is an operating system in which a small real-time kernel coexists with the Linux kernel which was originally developed by Victor Yodaiken at the New Mexico Institute of Mining and Technology.RTLinux supports hard real-time operation through interrupt control between the hardware and the operating system. Interrupts needed for deterministic processing are processed by the [...]

The Dynamic Host Configuration Protocol (DHCP) allows you to specify network parameters on a server and have client computers query the server for their information such as IP, netmask, gateway, DNS, etc Daemon :dhcpd The configuration file: dhcpd.conf Typical dhcpd.conf look like thiis ddns-updates on; ddns-update-style ad-hoc; option domain-name-servers 10.0.0.1, 202.188.0.133, 202.188.1.5; option subnet-mask 255.255.255.0; [...]

The File Transfer Protocol (FTP) is used as one of the most common means of copying files between servers over the Internet.It is the simplest way to exchange files between computers on the internet.With a simple command line interface ,a user can use FTP to perform updates,deletes,renames,moves of the files at a server. Types of [...]

NFS stands for Network File System, and is a way to share files between machines as if they were on your local hard drive.Linux can be both an NFS server and an NFS client, which means that it can export filesystems to other systems,and mount filesystems exported from other machines. Package required for NFS:nfs-utils Daemon: [...]

STEP 1: (The settings for the initial IP address) $ cat /etc/sysconfig/network-scripts/ifcfg-eth0 DEVICE=eth0 BOOTPROTO=static BROADCAST=192.168.99.255 IPADDR=192.168.1.155 NETMASK=255.255.252.0 NETWORK=192.168.1.0 ONBOOT=yes STEP 2 (2nd IP address: ) $cat /etc/sysconfig/network-scripts/ifcfg-eth0:1 DEVICE=eth0:1 BOOTPROTO=static BROADCAST=192.168.99.255 IPADDR=192.168.1.182 NETMASK=255.255.252.0 NETWORK=192.168.1.0 ONBOOT=yes Note:In STEP 1 the filename is “ifcfg-eth0″, whereas in STEP 2 it’s “ifcfg-eth0:1″ and also not the matching entries for “DEVICE=…”. [...]