Thanks Strahil and Sandro for your replies and sorry for the delay. @strahil [main] gpgcheck=1 installonly_limit=3 clean_requirements_on_remove=True best=True skip_if_unavailable=False Which it just is the original dnf.conf. To this, we'd apply the proxy settings written above the question. But we reach the SSL error. @sandro Unfortunately we can not use the smart proxy. We cannot install applications. Katello rpm as an example. We have our Foreman in place and we can download the 'katello-ca-consumer-latest.noarch.rpm' using CURL. But, when trying to install it, 'yum localinstall katello-ca-consumer-latest.noarch.rpm', it requires 'subscription-manager' as dependency package, which is not installed/included in CentOS8/RHEL8 and fails. Foreman is for the moment excluded. It could be interesting to fix the SSL/proxy issue, we haven't yet found how to fix it. Maybe you could address us, please? Thanks