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.
These requirements are the minimum requirements.
A server that meets only these requirements may not function properly, especially if the server runs certain demanding functions. Known issues include unsuccessful mail deliveries and websites that do not serve properly when they are called.
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.
Required tasks
Make certain that you complete the following tasks before you install your operating system or any cPanel product:
-
Register your fully qualified hostname — This hostname cannot be the same as any domain that is on your server (for example, if
example.comis a domain on your server, registerhostname.example.comas your fully qualified hostname). -
Define the IP address, subnet address, and default gateway IP address for your server — Your service provider can provide you with this information.
Before you install cPanel & WHM or cPanel DNSONLY, make certain that your server’s hardware meets all of the minimum requirements for new installations.
64-bit operating systems use more RAM than 32-bit systems.
How to choose a server
When you choose a server, you should consider the following questions:
- How many sites do you plan to host?
For example, if your server will host a large number of websites, which will each have associated email addresses and databases, the server will require more processing power, disk space, and RAM.
- What kind of web hosting you plan to do?
While cPanel & WHM will run on the minimum requirements below, the server will need more processing power, disk space, and RAM if you plan to host videos, music, or high-volume applications like forums.
Hardware requirements
|
Component
|
Minimum
|
Recommended
|
|---|---|---|
| Processor | 226 MHz | 226 MHz |
| Memory |
512 MB of RAM |
1 GB of RAM |
| Disk Space |
20 GB of disk space |
40 GB of disk space |
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:
Fatal! Perl must be installed before proceeding! |
In addition to the system Perl that you install before installation, cPanel & WHM servers use multiple Perl environments. For more information, read our Perl Environments and Modules documentation.
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.
We strongly recommend that you allow your operating system’s distribution to control the system Perl installation. Do not customize this Perl installation.
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
| Operating system | Additional restrictions |
|
CentOS versions 5.x and 6.x |
New installations of cPanel & WHM on CentOS servers must use CentOS version 6.0 or higher. |
| Red Hat Enterprise Linux® versions 5.x and 6.x | None. |
|
CloudLinux 5.x and 6.x |
cPanel does not support the use of Xen PV (paravirtualization) with CloudLinux. |
We support all of the official production release kernels for these operating systems.
Supported virtual environments
| Virtual environment | Additional restrictions |
| KVM | None. |
| Linux-VServer | None. |
|
Microsoft Server® 2008 Hyper-V |
cPanel only supports the drivers and configurations that Microsoft provides. |
|
OpenVZ |
|
| Oracle VM VirtualBox, VirtualBox OSE | None. |
|
Virtuozzo™ |
CloudLinux is not compatible with Virtuozzo. |
| VMware® Server, VMware ESX Server | None. |
| Xen, XenEnterprise™, XenExpress™, XenServer™ | None. |
Virtual environments that are detected and reported as functional
| Virtual environment | Additional restrictions |
|
SmartOS |
In order for cPanel & WHM to detect SmartOS, you must use cPanel & WHM version 11.36.1 or higher. |
Recommended file system
When you install your operating system, we recommend that you use an ext filesystem (ext2, ext3, or ext4).
If you use theext4filesystem, 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
|
Partition Name
|
Size
|
|---|---|
| / |
Grow to fill disk (40 GB recommended, 20 GB minimum) Note
To host a greater number of accounts, allocate more disk space to this partition.
|
| swap | See recommended swap space. |
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.
Advanced partition information is available in our Pre-Installation Options documentation.
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:
|
Partition
|
Number of inodes
|
|---|---|
/home |
Add at least 50,000 inodes per cPanel account. |
/usr |
Add 100,000 inodes. |
/var |
Add 2,000 inodes, plus 100 inodes per account that you plan to host. |
/tmp |
Add 50% of the default value. |
/boot and swap |
Use default values. |
Recommended swap space
|
For CentOS 5 |
|
| RAM | Minimum swap space |
|---|---|
| 4 GB or less | 2 GB |
| 4 GB to 16 GB | 4 GB |
| 16 GB to 64 GB | 8 GB |
| 64 GB to 256 GB | 16 GB |
| 256 GB to 512 GB | 32 G |
|
For CentOS 6 |
|
| RAM | Minimum swap space |
|---|---|
| 2 GB or less | Two times the amount of RAM on the server. |
| 2 GB to 8 GB | The same as the amount of RAM on the server. |
| 8 GB to 64 GB | Half the amount of RAM on the server. |
| 64 GB or more | 4 GB |
Install cPanel & WHM
To install cPanel & WHM, run the following commands:
-
To open the
/homedirectory, run the following command:cd/home -
To install GNU Wget, which you can use to retrieve installation files with HTTP, HTTPS, and FTP, run the following command:
yuminstallwget -
To fetch the latest installation files from cPanel’s servers, run the following command:
wget -N http://httpupdate.cpanel.net/latest -
To open and execute the installation files, run the following command:
sh latest