Document link:  https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/9/html/upgrading_from_rhel_8_to_rhel_9/performing-post-upgrade-tasks-on-the-rhel-9-system_upgrading-from-rhel-8-to-rhel-9#performing-post-upgrade-tasks-rhel-8-to-rhel-9_performing-post-upgrade-tasks-on-the-rhel-9-system

Section number and name: 

7.1.2.iii 

Remove remaining RHEL 8 packages from your RHEL 9 system. To ensure that RPM dependencies are maintained, use the dnf remove command.

Describe the issue:

The command in the document:

     # dnf remove $(rpm -qa | grep \.el[78] | grep -vE 'gpg-pubkey|libmodulemd|katello-ca-consumer`)

Correct command:

     # dnf remove $(rpm -qa | grep \.el[78] | grep -vE 'gpg-pubkey|libmodulemd|katello-ca-consumer')

Impact of this issue:

The command does not work and does not exit.

Suggestions for improvement:

     # dnf remove $(rpm -qa | grep \.el[78] | grep -vE 'gpg-pubkey|libmodulemd|katello-ca-consumer')