Install Perl Modules on CentOS 6

sudo yum install perl-CPAN
sudo cpan
say "yes" to everything

I had an error about missing perl-YAML, sudo yum install perl-YAML, as well.

Can't Install Modules and Themes From Drupal Page on CentOS 6

This is the error message that I got.

Run command "sudo setsebool -P httpd_can_network_connect on", it might take a few minutes for it to fully complete.

Setup SSH Option on Drupal Module and Theme Update on CentOS 6

yum -y install php-pear php-devel gcc libssh2-devel
pecl install "channel://pecl.php.net/ssh2-0.12"
echo extension=ssh2.so > /etc/php.d/ssh2.ini
service httpd restart

This is what happens afterwards.

Name-based Virtual Hosting

/etc/httpd/conf/httpd.conf

NameVirtualHost *:80

< VirtualHost *:80 >
    ServerAdmin webmaster@dummy-host.example.com
    DocumentRoot /var/www/html/drupal
   ServerName example.com
    ErrorLog logs/example.com-error_log
    CustomLog logs/example.com-access_log common
</ VirtualHost >

service httpd restart

Install VirtualBox Guest Additions for CentOS 6

1) Make sure the computer has network connection
2) mkdir rpm
3) cd rpm

Location of RPMForge for CentOS: http://wiki.centos.org/AdditionalResources/Repositories/RPMForge
Download the rpmforge-release package. Choose one of the two links below, selecting to match your host's architecture. If you are unsure of which one to use you can check your architecture with the command uname -i

i686 http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el6.rf.i686.rpm
x86_64 http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el6.rf.x86_64.rpm

4) wget http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el6.rf.i686.rpm
5) rpm --import http://apt.sw.be/RPM-GPG-KEY.dag.txt
6) rpm -i rpmforge-release-0.5.3-1.el6.rf.i686.rpm
7) yum install dkms
8) y
9) Devices -> Insert Guest Additions CD image...
10) mount -t iso9660 /dev/dvd1 /media
11) cd /media
12) sh ./VBoxLinuxAdditions.run
13) It will complain of missing kernel-devel-x..., do a yum install kernel-devel-x... whatever version it is.
14) sh ./VBoxLinuxAdditions.run

Now you can use commands such as, vboxmanage guestcontrol

CentOS 6 Running Out Of Space

Error message: At least 2MB more space needed on the /boot filesystem.

rpm -qa | grep kernel
Resulting grep:
kernel-2.6.32-71.el6.x86_64
kernel-2.6.32-71.29.1.el6.x86_64
kernel-2.6.32-131.0.15.el6.x86_64

Newest one is 2.6.32-504
Remove all except the most recent one
rpm -e kernel-2.6.32-71.el6.x86_64 kernel-2.6.32-71.29.1.el6.x86_64

Update kernel
yum -y update kernel

Update other things (optional)
yum -y update

Reference: http://www.cyberciti.biz/faq/installing-kernel-2-6-32-131-2-1-el6-x86_64-needs-8mb-on-boot-filesystem/