We encountered the error message ‘This system is not registered with an entitlement server, You can use “rhc” or “subscription-manager” to register’. On CentOS Stream 9 Linux system while trying to perform package installations. For RHEL, this usually is an indication that your system is not registered with Red Hat’s subscription management service.

$ sudo dnf clean all
Updating Subscription Management repositories.
Unable to read consumer identity

This system is not registered with an entitlement server. You can use "rhc" or "subscription-manager" to register.

21 files removed

Here is how we solved the issue on the system. Open the following file for editing:

sudo vi /etc/dnf/plugins/subscription-manager.conf

Change from enabled=1 to enabled=0:

[main]
enabled=0

# When following option is set to 1, then all repositories defined outside redhat.repo will be disabled
# every time subscription-manager plugin is triggered by dnf or yum
disable_system_repos=0

You can then update package cache and try install your packages.

For RHEL system, run the following command to register your system with the Red Hat Subscription Manager:

sudo subscription-manager register --username <your_username> --password <your_password>

Remember to replace use correct username and password for your Red Hat account. After successful registration, attach a subscription to the system:

sudo subscription-manager attach --auto

Check if subscription was successful and list of repositories the system has access to:

sudo subscription-manager status

To enable a specific repository, run:

sudo subscription-manager repos --enable=<repository_name>

Listing of available repositories can be done using:

sudo subscription-manager repos --list

Enjoy using your CentOS Stream or Red Hat Enterprise Linux system!.