https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/9/html-single/installing_identity_management/index#prerequisites
 
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  Chapter 28 refers to a package installation that is from the Red Hat iDM installation of RHEL 8.

yum module for iDM are not available on RHEL 9.

`` dnf install ipa-server-dns ` is required.