Most of the  production servers  has limited connectivity to the Internet. If they have any connectivity then probably it  will be through a forward proxy server. If your server is behind the proxy server, then you need to provide proxy server details in /etc/yum.conf.. The proxy setting must specify the proxy server as a complete [...]

With every new kernel update, you receive another boot loader menu item. It will also eat up space from your /boot partition. If you don’t want your /boot partition to be filled up, then you need to remove some of the old kernels. How do we do it? First let’s get the list of kernels [...]

If you use date command without any parameter, it will print the current date and time. [root@centos ~]# date Thu Jan 7 18:33:48 CET 2010 You can use the same command to set/change your system date and time. Notation for this usage as listed below. date MMDDhhmmYYYYY Let’s say that we would like to set [...]

VMWare has a yum repository for vmware tools related rpms. Before we do the vmware tools installation we need to define this repository on our server. Let’s start with importing the public key for the vmware packages. rpm –import http://packages.vmware.com/tools/VMWARE-PACKAGING-GPG-KEY.pub Now it is time to create a .repo file for our repositoy. This file needs [...]

Timezone information for your system is defined in the /etc/localtime file. By changing this file you can change time zone for your server. You don’t need to modify this file manually. /usr/share/zoneinfo/ folder contains time zone files you would need. Let’s say that we want set the time zone for our server to Europe/Amsterdam. Then [...]

There are two possible ways for adding a default gateway. Option 1: You can add a gateway definition to  the /etc/sysconfig/network file. This definition will apply to all network interfaces. Let’s say that your gateway is 192.168.4.1,  then you need to add the following line to /etc/sysconfig/network file. GATEWAY=192.168.4.1 Option 2: You can define a [...]

After doing a kernel upgrade, default kernel configuration in GRUB config will be automatically update. On Redhat based systems you can change this behavior by modifying /etc/sysconfig/kernel file. You need to set the UPDATEDEFAULT to no. UPDATEDEFAULT=no

Redhat bases systems are using yum as their package manager. Yum repository definitions are stored in .repo files located in /etc/yum.repos.d/ directory and by adding a new file repo file you can define additional repositories. This file needs to contain at least following information. [repositoryid] name=Some name for this repository baseurl=url://path/to/repository/ repositoryid is need to [...]

We can disable SELinux by editing the /etc/selinux/config configuration file. We will need to change the following line SELINUX=enforcing as listed below. SELINUX=disabled After this modification we need to reboot our system. advertise