To allow conversions from older non-latest RHEL 8 versions we need to adapt convert2rhel to know where to find those repos and how to download and backup them.

Why can't we use the repofiles that are already on the system?
First, we don't know what repos the customer has enabled on the system. Second, the default repositories installed with either CentOS or Oracle Linux point only to the latest minor version. For example in case of CentOS Linux, to be able to access older minor version packages, the system needs to add new repos pointing to CentOS Vault - an archive of older system versions. Vault repos are not being installed on the system by default.

Where to get the repofiles for CentOS and Oracle Linux?
For CentOS 8.4: https://vault.centos.org/8.4.2105/BaseOS/x86_64/os/Packages/centos-linux-repos-8-3.el8.noarch.rpm
For Oracle Linux 8.4: Taken from a ISO image for the latest 8.4 version

What is expected from this:

• Copy the hardcoded repositories to a specific location in the machine (Probably, /var/convert2rhel/temp);
• Adapt the code so that when we detect the repos folder inside the 8/x86_64 directory we don't download package backups or check if the system is up-to-date with the system repos, but instead, we do that by using our own hardcoded repositories;
• Use rpm2cpio to extract repofiles from rpms in the mirror/vault pages
  • Example: rpm2cpio centos-release*.noarch.rpm |cpio -id

Acceptance Criteria:

• A new directory (presumably, repos) is added to the 8/x86_64 directory in convert2rhel under each supported RHEL clone folder (CentOS/Oracle Linux);
• Add a .repo file in this new directory corresponding with the supported EUS versions for each clone;
  • For CentOS Linux is expected to have 8.4 and 8.5;
  • For Oracle Linux is expected to have 8.4 only;
• The new key for Alma/Rocky/Scientific (Any non-official supported systems) should be empty for MVP