Last modified: 2025 September 18

Overview

The FastUpdate Cache system serves as an on-demand cache for your servers. This system accepts update requests from cPanel & WHM servers and provides them with the most recent software versions. The FastUpdate Cache system allows you to speed up new feature installations for your cPanel & WHM servers.

A FastUpdate Cache server provides the following benefits:

• Provides cPanel & WHM updates from the httpupdate servers when you request them.
• Reduces redundant file transfers outside of your network when you download new features.
• Simplifies the cPanel & WHM deployment practices for current customers in the httpupdate network.
• Allows an easy method for you to participate in the httpupdate network.

When you install the FastUpdate Cache package, you can configure your cPanel & WHM servers to download updates from the mirror. You can also open a customer support ticket and request to participate in the httpupdate mirror system.

How do I create a FastUpdate Cache mirror?

Before you create a FastUpdate Cache mirror, install the firewalld daemon on the server. To do this, run the following commands:

sudo dnf install firewalld
sudo systemctl enable firewalld
sudo systemctl start firewalld

To install the FastUpdate Cache Package, perform the following steps:

1. Log in to the server as the root user via SSH.
2. Run the following script:

curl -L https://updateseeds.cpanel.net/install-almalinux9.sh | sh

The script performs the following actions:

• Installs required dnf repositories.
• Installs the collectd daemon and the Varnish web accelerator cache.
• Configures the collectd daemon to function on the server.
• Configures the Varnish web accelerator to function on the server.
• Configures the Varnish web accelerator’s firewall to open port 80.

To include your FastUpdate Cache server in Trusted Rotation, open a support ticket with the following title:

cPanel FastUpdate Partner Verification Request

How do I view a list of servers that my FastUpdate Cache server monitors?

To return a list of servers that a FastUpdate Cache server monitors, enter the following URL in a web browser:

https://updateseeds.cpanel.net/fastupdate_sources.pl

This URL returns a list of server IP addresses that the FastUpdate Cache server monitors, one per line. For example:

http://208.74.121.35/
http://208.74.121.41/

How do I troubleshoot FastUpdate errors?

The following sections list some common FastUpdate Cache server errors and how to troubleshoot them.

Installation errors

Your server does not possess enough free disk space.

The server on which you install the FastUpdate Cache package must contain at least 40 GB of available disk space. If your server contains less than this amount, the system returns the following error message:

Jul 29 08:49:20 whm-11-50-c7.vm.local varnishd[6100]: Error: (-sfile) size "40G":
larger than file system

To troubleshoot this error, increase the available disk space on your server to at least 40 GB and run the installation script again.

You execute the installation script as a non-root user.

If you attempt to execute the FastUpdate Cache package installation script as a user other than the root user, the system returns the following error message:

You must run this command as root.

To troubleshoot this issue, log in to the server as the root user and run the installation script again.

You execute the installation script on a server that runs AlmaLinux 8 or earlier.

If you attempt to execute the FastUpdate Cache package installation script on a non-AlmaLinux 9 server, the system returns the following error message:

You must install the package on AlmaLinux 9

To troubleshoot this issue, confirm that AlmaLinux 9 exists on your server and run the installation script again.

You leave SELinux enabled on the server.

You must set SELinux to run in permissive mode, or disable SELinux, before you attempt to install the FastUpdate Cache package. If you do not perform either of these actions, Varnish cannot install.

If you attempt to execute the FastUpdate Cache package installation script on a server with SELinux in enforcing mode, the system returns the following error message:

SELinux cannot run in 'enforcing' mode. Set the 'SELINUX’ line to ‘disabled' or
'permissive' in the /etc/selinux/config file, run the 'setenforce 0’ command, and
rerun the installation script.

To disable SELinux, open the /etc/selinux/config file with a text editor and set the SELINUX line to permissive or disabled. For example:

SELINUX=disabled

After you perform this action, run the setenforce 0 command and run the installation script again.

SELinux cannot run in 'enforcing' mode. Run the ‘setenforce 0’ command and rerun

Post-installation errors

If the FastUpdate Cache package installs correctly on your server, but the server does not function, one of the following issues may exist:

The http-varnish Varnish daemon does not currently run on the server.

A FastUpdate Cache mirror requires the http-varnish daemon to run on the server. If the http-varnish daemon does not run on the server, the system returns an error message that resembles the following example:

Failed to issue method call: Unit httpupdate-varnish.service failed to load: No such
file or directory.

To troubleshoot this issue, disable the systemctl varnish daemon and enable the http-varnish daemon. To do this, run the following series of commands:

systemctl stop varnish
systemctl disable varnish
systemctl enable httpupdate-varnish
systemctl start httpupdate-varnish

For more information, read Varnish Cache’s Troubleshooting Varnish documentation.

More than one service's firewall attempts to listen on port 80.

You can only configure one service’s firewall to open port 80. If more than one service attempts to open port 80, your FastUpdate Cache server cannot function.

To troubleshoot this issue, remove one of the services whose firewall attempts to open port 80. To do this, run the following series of commands:

firewall-cmd --permanent --zone=public --remove-service=https
firewall-cmd --reload