Packages that are part of RHEL Server Optional repository are part of CentOS base repository. Use has no way of knowing that those packages won't be converted and even after conversion is not informed about them.

Steps to reproduce:

1. Install CentOS-7.9 on x86_64 system
2. Update packages and reboot
3. Install boost-doc package
4. Follow instructions from https://access.redhat.com/documentation/en-us/red_hat_insights/2023/html/converting_from_an_rpm-based_linux_distribution_to_rhel_using_red_hat_insights/proc_preparing-for-a-rhel-conversion-using-insights_converting-from-a-linux-distribution-to-rhel-in-insights
5. Run "Pre-conversion analysis for converting to RHEL" task
6. Check result of the "Pre-conversion analysis for converting to RHEL" task (see screenshot)
7. Run "Convert to RHEL from CentOS Linux 7" task
8. Check result of the "Pre-conversion analysis for converting to RHEL" task (see screenshot)
9. Check enabled repositories:

# yum repolist
Loaded plugins: fastestmirror, product-id, search-disabled-repos, subscription-manager
Loading mirror speeds from cached hostfile
repo id                                                                                                        repo name                                                                                                     status
client-tools-for-rhel-7-server-rpms/x86_64                                                                     Red Hat Client Tools for RHEL 7 x86_64                                                                            15
rhel-7-server-rpms/7Server/x86_64                                                                              Red Hat Enterprise Linux 7 Server (RPMs)                                                                      34,094
repolist: 34,109

1. Check the vendor of boost-doc package:

# rpm -q --queryformat "%{VENDOR}\n" boost-doc
CentOS

The same situation is with yum-plugin-fastestmirror package which is installed by default.

The main problems here are:

• the system is left in a state where most of the packages are provided by RHEL and with corresponding repositories enabled while other packages remain from CentOS and no longer have repository which may lead to a state where upgrading of the RHEL packages will not be possible due to broken dependencies (when CentOS packages depend on specific version of RHEL packages)
• user is not informed about these packages silently remain unconverted