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CentOS Change Timezone

After installing CentOS we sometimes see that the date is not in our desired timezone, instead it defaulted to the PST timezone.

Correcting your timezone is an easy operation, so here is a quick guide to change your CentOS timezone configuration file.

Firstly you’ll need to know your timezone and/or country, a list can be found in /usr/share/zoneinfo/

The more generic procedure to change the timezone is to create a symlink to file /etc/localtime

# ln -sf /usr/share/zoneinfo/Africa/Johannesburg /etc/localtime

OR you can copy and replace the current localtime setting

# cp /usr/share/zoneinfo/Africa/Johannesburg /etc/localtime

To verify that your timezone is changed use the date command:

# date
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Remove all i386 packages from CentOS 5 x86_64

A quick solution to duplicate packet installation. This tutorial will show you how to remove all i386 packages from CentOS 5 x86_64 server

# yum remove \*.i\?86
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BIOS and Firmware Updates Using Dell Linux Repository

You can update your CentOS 6 system to the latest version or to a specific version of the BIOS and firmware available in the Dell Linux online repository. You can inventory your CentOS 6 system, scan the repository for matching firmware with newer version using repository management software such as yum.

Firmware-tools are used to update BIOS and firmware on your system. Using a repository management software, you can easily update your BIOS and firmware to the latest or specific versions on your system.

Setting Up/Bootstrapping the Repository

To setup/bootstrap the Dell Linux online repository on your CentOS 6 sever, run the following command at the command prompt:

# wget -q -O - | bash

The system is configured to access the Dell Linux online repository using supported repository management software. The Dell GPG keys and libsmbios (BIOS library) are also installed.

Installing Firmware Tools

# yum install dell_ft_install

Downloading Applicable Firmware

# yum install $(bootstrap_firmware)

You can also inventory your system for the list of existing versions of BIOS and firmware using the following command:

# inventory_firmware

Updating BIOS and Firmware Using CLI

Run the following command to inventory the system and scan the repository for new versions of components:

# update_firmware

This command provides information about the existing versions of components on your system and the list of component versions that are available to be installed.

To install all applicable BIOS and firmware updates on your system, run the following command:

# update_firmware --yes

Once the devices are updated, the “Execution Success” message is displayed.

Automatically Update Firmware

By default, installing a BIOS or firmware RPM does not apply the update to the hardware. The update is manually applied using the update_firmware command. However, you can automatically update the hardware during RPM installation by configuring the /etc/firmware/firmware.conf file.

To automatically install BIOS and firmware updates, ensure that rpm_mode is set to auto in the firmware.conf file as shown:


# Automatically install BIOS updates when an RPM BIOS Update file is installed
# values: 'auto', 'manual'
# default: 'manual'

Viewing Log Information

# cat /var/log/firmware-updates.log
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CentOS: Configure network

This tutorial is intended for system administrators wanting to either change the IP address or add additional LAN cards (NIC) on their CentOS 5 system. There are a couple of ways to configure the network card using the command line but only some commands will take immediate effect on kernel. If you are doing this remotely remember that you will lose connectivity or if your configuration on your network is incorrect be unable to connect.

Configure network with immediate effect

Using a single command line to configure the network

# ifconfig eth0 netmask


# ip addr add dev eth0