how to install virtualBox 4.3 on Fedora/CentOS/RHEL

Oracle VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as home use. VirtualBox is a general-purpose full virtualizer for x86 hardware. Targeted at server, desktop and embedded use, it is now the only professional-quality virtualization solution that is also Open Source Software.
VirtualBox supports a large number of guest operating systems:
Windows 3.x
Windows NT 4.0
Windows 2000
Windows XP
Windows Server 2003
Windows Vista
Windows 7
Windows 8
Windows 8.1
DOS
Linux (2.4, 2.6, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 3.10, 3.11)
Solaris
OpenSolaris
OpenBSD
This guide shows howto install VirtualBox 4.3 (currently 4.3.20) on Fedora 21/20/19/18/17, CentOS 7/6.6/5.11, Red Hat (RHEL) 7/6.6/5.11. This guide uses Virtual Box own yum repositories.
Note: Fedora 16 users can install VirtualBox 4.2, Fedora 15/14 users can install VirtualBox 4.1, Fedora 13 users can install VirtualBox 4.0 and Fedora 12 users can install VirtualBox 3.2.

1. Change to root User
#su -

2. Install Fedora or RHEL Repo Files
#cd /etc/yum.repos.d/


Fedora 21/20/19/18/17/16/15/14/13/12 users
#wget http://download.virtualbox.org/virtualbox/rpm/fedora/virtualbox.repo

CentOS 7/6.6/5.11 and Red Hat (RHEL) 7/6.6/5.11 users
wget http://download.virtualbox.org/virtualbox/rpm/rhel/virtualbox.repo




3. Update latest packages and check your kernel version
Update packages
#yum update

Check that that you are running latest installed kernel version
Output of following commands version numbers should match:
Shell

#rpm -qa kernel |sort -V |tail -n 1
#uname -r

Note: If you got kernel update or run older kernel than newest installed then reboot:
Shell

#reboot




4. Install following dependency packages
CentOS 7/6/5 and Red Hat (RHEL) 7/6/5 needs EPEL repository, install it with following command:

CentOS 7 and RHEL 7 
rpm -Uvh http://dl.fedoraproject.org/pub/epel/7/x86_64/e/epel-release-7-5.noarch.rpm

CentOS 6 and RHEL 6
rpm -Uvh http://dl.fedoraproject.org/pub/epel/6/i386/epel-release-6-8.noarch.rpm

CentOS 5 and RHEL 5
rpm -Uvh http://dl.fedoraproject.org/pub/epel/5/i386/epel-release-5-4.noarch.rpm

#yum install binutils gcc make patch libgomp glibc-headers glibc-devel kernel-headers kernel-devel dkms

PAE kernel users install 
#yum install binutils gcc make patch libgomp glibc-headers glibc-devel kernel-headers kernel-PAE-devel dkms




5. Install VirtualBox Latest Version 4.3 (currently 4.3.20)

#yum install VirtualBox-4.3

Note:
This command create automatically vboxusers group and VirtualBox user must be member of that group.

you are  can download and install virtualbox manual from https://www.virtualbox.org/wiki/Downloads
if the download is finished,  please right click -> open with  package installer/


This command also build needed kernel modules.
Rebuild kernel modules with following command:

#/etc/init.d/vboxdrv setup
#service vboxdrv setup




6. Add VirtualBox User(s) to vboxusers Group
Replace user_name with your own user name or some another real user name.

#usermod -a -G vboxusers user_name




7. Start VirtualBox
Use launcher from menu or simply run:

#VirtualBox



Troubleshooting
If you have problems with KERN_DIR parameter or your kernel directory is not automatically detected then set KERN_DIR environment variable manually, using following method:

Current running kernel on Fedora
KERN_DIR=/usr/src/kernels/'uname -r'

Current running kernel on CentOS and Red Hat (RHEL
KERN_DIR=/usr/src/kernels/'uname -r'-'uname -m'

Fedora example
KERN_DIR=/usr/src/kernels/2.6.33.5-124.fc13.i686

CentOS and Red Hat (RHEL) example ##
KERN_DIR=/usr/src/kernels/2.6.18-194.11.1.el5-x86_64

Export KERN_DIR
export KERN_DIR


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