Important information

Before you install cPanel & WHM or cPanel DNSONLY, you must know the following information:

• Because cPanel is designed for commercial hosting, we only license publicly visible, static IP addresses. We do not license dynamic, sticky, or internal IP addresses.
• We do not provide an uninstaller. After you install our software, you must reformat the server to remove it.
• Only install cPanel & WHM on a freshly installed operating system.
• We recommend that you use the cPanel & WHM installer, which will install all of the services that it needs. If you install services before you install cPanel & WHM, you will encounter compatibility problems. When you install your operating system, deselect software package groups like Gnome, KDE, or other GUI desktop environments.
• You will need a package handler like yum. This package handler is included in default installations of CentOS and Red Hat^® Enterprise Linux^®.

Overview

Before you install cPanel & WHM or cPanel DNSONLY, make certain that your system meets all of our minimum requirements for new installations.

Perl must be present on your server before the installation script for cPanel & WHM can run successfully. If Perl is not present during installation, the cPanel & WHM installer will attempt to install Perl via the yum -y install perl command. If this installation is not successful, you will see the following error message:

Perl versions

Your system Perl installation should be Perl 5.8.8 for RHEL 5 and CentOS™ 5 servers, or Perl 5.10 for RHEL 6 and CentOS 6 servers.

Manual installation

If you receive errors when the cPanel & WHM installer attempts to install Perl, make certain that yum functions correctly on your server.

To attempt to install Perl again, run the following command:

yum install perl

Supported operating systems

Supported virtual environments

Virtual environments that are detected and reported as functional

Recommended file system

When you install your operating system, we recommend that you use an ext filesystem (ext2, ext3, or ext4).

If you use the ext4 filesystem, you must download and install the package mentioned in the Red Hat documentation.

We only develop and test cPanel & WHM on file systems that support flock. Some network file systems (for example, NFS) may require additional configuration in order to function properly.

Recommended partitions

For some servers, additional partitions are beneficial. This is particularly true for servers with high email volume. The number of files that the operating system can access per partition is limited.

iNodes

In Linux, an inode is a filesystem object that contains the owner, permissions, and other important metadata. Every file, image, directory, email, and symbolic link on your server requires an inode.

On average, files on webservers are usually smaller than on other types of servers. Therefore, we recommend that you allocate more than the default number of inodes on your server’s partitions.

If you install everything on a single partition, the base cPanel installation requires at least 1,000,000 inodes, plus at least 50,000 inodes per cPanel account that you plan to host.

If you plan to use the partition scheme on the Advanced Partitioning Guide, add the following to the default number of inodes per partition:

Recommended swap space

Install cPanel & WHM

To install cPanel & WHM, run the following commands:

1. To open the /home directory, run the following command:

   cd /home

2. To install GNU Wget, which you can use to retrieve installation files with HTTP, HTTPS, and FTP, run the following command:

   yum install wget

3. To fetch the latest installation files from cPanel’s servers, run the following command:

   wget -N http://httpupdate.cpanel.net/latest

4. To open and execute the installation files, run the following command:

   sh latest