CentOS 6.2 Downloads

You can download CentOS 6.2 via the web/ftp server or via BitTorrent (recommended) client.

CentOS 6.2 DVD ISO downloads

• Download CentOS 6.2 32 bit DVD ISO CentOS-6.2-i386-bin-DVD1.iso and CentOS-6.2-i386-bin-DVD2.iso
• Download CentOS 6.2 64 bit DVD ISO CentOS-6.2-x86_64-bin-DVD1.iso and CentOS-6.2-x86_64-bin-DVD2.iso

CentOS 6.2 DVD ISO Torrents

Torrent files for the DVD’s are available at the following location:

• Download CentOS 64 i386 torrent file
• Download CentOS 64 x86_64 torrent file

When trying to update your server via the yum command you might see the following error / warning message:

Warning: RPMDB altered outside of yum.

# yum install nethogs
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: mirror.cogentco.com
* epel: mirror.cogentco.com
* extras: mirror.vcu.edu
* ius: mirror.rackspace.com
* updates: centos.aol.com
Setting up Install Process
Resolving Dependencies
–> Running transaction check
—> Package nethogs.x86_64 0:0.8.0-1.el6 set to be updated
–> Finished Dependency Resolution

Dependencies Resolved

====================================================================
 Package       Arch            Version          Repository     Size
====================================================================
Installing:
 nethogs      x86_64           0.8.0-1.el6      epel          28 k

Transaction Summary
====================================================================
Install       1 Package(s)
Upgrade       0 Package(s)

Total download size: 28 k
Installed size: 53 k
Is this ok [y/N]: y
Downloading Packages:
nethogs-0.8.0-1.el6.x86_64.rpm | 28 kB 00:00
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction

Warning: RPMDB altered outside of yum.

Installing : nethogs-0.8.0-1.el6.x86_64 1/1

Installed:
nethogs.x86_64 0:0.8.0-1.el6

Complete!

How do you fix this problem?

# yum clean all

After installing CentOS we sometimes see that the date is not in our desired timezone, instead it defaulted to the PST timezone. So here is a quick guide to change your local timezone.

Set timezone using /etc/localtime configuration file

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

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

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 - http://linux.dell.com/repo/hardware/latest/bootstrap.cgi | 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:

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[main]
 
# Automatically install BIOS updates when an RPM BIOS Update file is installed
# values: 'auto', 'manual'
# default: 'manual'
rpm_mode=auto

Viewing Log Information

# cat /var/log/firmware-updates.log

CentOS 6 Channel Bonding allows administrators to bind multiple network interfaces together into a single channel using the bonding kernel module and a special network interface called a channel bonding interface. Channel bonding enables two or more network interfaces to act as one, simultaneously increasing the bandwidth and providing redundancy.

CentOS 6 Channel Bonding

Channel bonding (also known as “Ethernet bonding”) is a computer networking arrangement in which two or more network interfaces on a host computer are combined for redundancy or increased throughput.

mode=0 (Balance-rr) – This mode provides load balancing and fault tolerance.
mode=1 (active-backup) – This mode provides fault tolerance.
mode=2 (balance-xor) – This mode provides load balancing and fault tolerance.
mode=3 (broadcast) – This mode provides fault tolerance.
mode=4 (802.3ad) – This mode provides load balancing and fault tolerance.
mode=5 (balance-tlb) – Prerequisite: Ethtool support in the base drivers for retrieving the speed of each slave.
mode=6 (balance-alb) – Prerequisite: Ethtool support in the base drivers for retrieving the speed of each slave.

Note: Always append extra configuration in case of a rollback.

Configuring Channel Bonding

# cd /etc/sysconfig/network-scripts/

# vi ifcfg-bond0

We’ll be using mode=6 (balance-alb)

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DEVICE=bond0
USERCTL=no
BOOTPROTO=none
ONBOOT=yes
IPADDR=10.0.0.10
NETMASK=255.255.0.0
NETWORK=10.0.0.0
BONDING_OPTS="miimon=100 mode=balance-alb"
TYPE=Unknown
IPV6INIT=no

# vi ifcfg-eth0

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DEVICE=eth0
BOOTPROTO=none
ONBOOT=yes
MASTER=bond0
SLAVE=yes
USERCTL=no

# vi ifcfg-eth1

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DEVICE=eth1
BOOTPROTO=none
ONBOOT=yes
MASTER=bond0
SLAVE=yes
USERCTL=no

# vi ifcfg-eth2

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DEVICE=eth2
BOOTPROTO=none
ONBOOT=yes
MASTER=bond0
SLAVE=yes
USERCTL=no

Due to the fact that /etc/modprobe.conf has been deprecated in CentOS 6, the process of bonding network interfaces has changed a bit.

Now instead of defining your bond in your /etc/modprobe.conf, you define it in /etc/modprobe.d/bonding.conf

# vi /etc/modprobe.d/bonding.conf

Append the following onto the end out your modprobe config file

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alias bond0 bonding

# servive network restart

If you really need to disable SELinux on CentOS 6 please consider the following:

# vi /etc/selinux/config

Change SELINUX=enforcing

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# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
#     enforcing - SELinux security policy is enforced.
#     permissive - SELinux prints warnings instead of enforcing.
#     disabled - No SELinux policy is loaded.
SELINUX=enforcing
# SELINUXTYPE= can take one of these two values:
#     targeted - Targeted processes are protected,
#     mls - Multi Level Security protection.
SELINUXTYPE=targeted

to SELINUX=disabled

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# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
#       enforcing - SELinux security policy is enforced.
#       permissive - SELinux prints warnings instead of enforcing.
#       disabled - SELinux is fully disabled.
SELINUX=disabled
# SELINUXTYPE= type of policy in use. Possible values are:
#       targeted - Only targeted network daemons are protected.
#       strict - Full SELinux protection.
SELINUXTYPE=targeted

This will disable SELinux on your next reboot.

To diable SELinux, without having to reboot, you can use the setenforce command like so:

# setenforce 0

This will revert to enforcing once you reboot

The assumption for this CentOS 5.7 tutorial is that you are running as root and have a basic understanding of the software required but if you follow this tutorial you should be able to complete the task successfully.

# yum install yum-priorities

Installing PHP 5.3 on CentOS 5.7 x86_64

Install the EPEL x86_64 Repo

# rpm -Uvh http://download.fedora.redhat.com/pub/epel/5/x86_64/epel-release-5-4.noarch.rpm

Install the IUS x86_64 Repo

# rpm -Uvh http://dl.iuscommunity.org/pub/ius/stable/Redhat/5/x86_64/ius-release-1.0-8.ius.el5.noarch.rpm

# yum install php53u php53u-common php53u-devel

# php -v
PHP 5.3.8 (cli) (built: Aug 23 2011 06:33:32)
Copyright (c) 1997-2011 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2011 Zend Technologies

Installing PHP 5.3 on CentOS 5.7 i386

Install the EPEL i386 Repo

# rpm -Uvh http://download.fedora.redhat.com/pub/epel/5/i386/epel-release-5-4.noarch.rpm

Install the IUS i386 Repo

# rpm -Uvh http://dl.iuscommunity.org/pub/ius/stable/Redhat/5/i386/ius-release-1.0-8.ius.el5.noarch.rpm

# yum install php53u php53u-common php53u-devel

# php -v
PHP 5.3.8 (cli) (built: Aug 23 2011 06:33:32)
Copyright (c) 1997-2011 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2011 Zend Technologies

Before upgrading CentOS 5.6 to 5.7 it cannot be stressed enough how important it is to make a backup of your system before you do this. Actions listed in this post are written with the assumption that they will be executed by the root user running the bash or any other modern shell.

Clean All Packages

# yum clean all

The following command will get a list of packages that are going to be updated.

# yum list updates

Upgrade CentOS 5.6 to 5.7

# yum update

Finally reboot the server for Kernel changes to take effect

# reboot

Verify that CentOS 5.7 is working:

# cat /etc/redhat-release
CentOS release 5.7 (Final)

Or:

# lsb_release -a
LSB Version: :core-4.0-amd64:core-4.0-noarch:graphics-4.0-amd64:graphics-4.0-noarch:printing-4.0-amd64:printing-4.0-noarch
Distributor ID: CentOS
Description: CentOS release 5.7 (Final)
Release: 5.7
Codename: Final

Or:

# rpm -q centos-release
centos-release-5-7.el5.centos

CentOS 5.7 is now available (see download link at the end of the article) for both 32-bit and 64-bit architectures and it is based on the upstream release of Red Hat Enterprise Linux 5.7. It contains lots of updates, bugfixes and new features.

CentOS 5.7 Downloads

You can download CentOS Linux 6 via the web/ftp server or via BitTorrent (recommended) client.

CentOS 5.7 DVD ISO downloads

• Download CentOS 5.7 32 bit i386 DVD ISO Local Mirror
• Download CentOS 5.7 64 bit x86_64 DVD ISO Local Mirror

CentOS 5.7 DVD ISO Torrents

Torrent files for the DVD’s are available at the following location:

• Download 32 bit i386 torrent file
• Download 64 bit x86_64 torrent file