Hi guys.

What options such as '--dnf-cmd' do, can you tell?

E.g.,

  mock --dnf-cmd debuginfo-install PACKAGE

is equivalent (very simplified) to:

  chroot $chroot

  dnf debuginfo-install PACKAGE

dnf-cmd is command, not an option. So you cannot combine --rebuild and --dnf-cmd.

> At the same time - I hit something which might be common I'd imagine:

...

  - cannot install the best update candidate for package mpfr-3.1.6-1.el8.x86_64
  - cannot install both mpfr-4.1.0-8.el8.x86_64 and mpfr-3.1.6-1.el8.x86_64
  - cannot install both mpfr-3.1.6-1.el8.x86_64 and mpfr-4.1.0-8.el8.x86_64
(try to add '--skip-broken' to skip uninstallable packages or '--nobest' to use not only best candidate packages)

This is problem of repository and needs to be fixed there.

As a workaround you can modify your config and set

config_opts['dnf.conf'] = """
[main]

...

best=0

...

"""

But this will silently hides new version of packages from you and may result to builds which may have broken deps on current distribution.

Miroslav