Troubleshooting a Recent Installation

For cPanel & WHM version 11.40

If you have installed cPanel and WHM according to our documentation and are still experiencing problems, there are steps that you can take to identify and resolve the issue.

How to Fix RPM Installation Failures

There are several reason your installation could fail due to an issue with the RPMs. To learn more about these failures, visit our document on RPM Installation Failures.?

Checking Resolvers

If you are having DNS problems, ensure that the server has a list of functional resolvers. Resolvers allow the server to find IP addresses corresponding to domain names by communicating with DNS servers.

If you need to add resolvers to your server:

  1. Open /etc/resolv.conf with a text editor (such as nano).
  2. If no resolvers have been entered into the configuration file, type nameserver $IP where $IP is meant to represent the IP address of the resolver.
    • You should be able to obtain at least 2 resolvers from your data center.

To make sure the resolver is working properly:

  1. Open a terminal session.
  2. Type host, where can represent any domain.
    • For example: host
  3. If results are returned to the server, the resolvers have been properly configured.

Examining the CPU and Memory

Once the resolvers are added and the system has been checked, you may want to examine your directories and partitions to ensure they are properly configured.

  • Use the command df -h to view information about all the currently mounted file systems.
  • Use the command free -m to view information about the server’s available memory.
  • Use the command cat /proc/cpuinfo to view information regarding the server’s processing power.
  • Use the command cat /proc/meminfo to view more detailed information regarding the server’s memory.

Deactivating the Firewall

If you have a firewall running, you will need to disable it prior to running the cPanel installation. Red Hat and CentOS distributions allow you to disable the firewall during the operating system’s installation configuration. This is the recommended method.

However, this can also be accomplished in Red Hat and CentOS by running the following commands in your command line interface:

  • /etc/init.d/iptables save
  • /etc/init.d/iptables stop

The OS firewall must remain disabled in order for WHM and cPanel to run on your web server. When the installation is complete, you will need to configure your firewall using a third-party client. cPanel recommends using APF or CSF.

Verifying the License

If you suspect that your cPanel and WHM license is not functioning:
  1. Run either of the following commands from your server’s command line interface:
    • curl -L
    • lynx -dump
  2. Next, visit
  3. Enter the IP address you obtained in step 1.
    • Our website will display the status of your license.

If your server’s IP (from step 1) does not match the IP address on your license, contact cPanel Customer Service for further assistance.

If your IP address matches the license, and you are still experiencing problems, run the following script to verify your license:

  • /usr/local/cpanel/cpkeyclt

Once the script runs, you should be returned promptly to the command line with no messages if it works properly. If it takes longer than a few seconds, you may be experiencing connectivity issues.

If cpkeyclt fails, ensure that you are able to resolve our licensing servers. To test that you can resolve our servers. use the following command:

  • host

You may also need to ensure that the time and date of the server are not set too far into the future or past.

Checking Browser Compatibility

Updates to cPanel & WHM 11.36 were tested in the following operating systems:
  • Windows 7
  • Mac OS 10.6, 10.7, 10.8
Updates to cPanel & WHM 11.36 were tested and are compatible with the following browsers: Updates to cPanel & WHM 11.36 were not tested, but have limited compatibility with the following browsers:
  • Microsoft Internet Explorer 6 and 7
  • Opera 12
  • Safari 5.1 and above
  • note Note: In these browsers, specific features related to email are supported. The pages in cPanel & WHM 11.36 will likely function, but there may be minor defects or inconveniences related to specific functionality.

Topic revision: r23 - 19 Sep 2013 - 18:03:27 - Main.JenniferDoubrava