Description of problem: yum has a setopt option which is quite useful --setopt=option=value Set any config option in yum config or repo files. For options in the global config just use: --setopt=option=value for repo options use: --setopt=repoid.option=value
this is supported already, just not yet documented.
Fixed by d21561b, will be included in dnf-0.4.10.
dnf-0.4.10-1.fc20 has been submitted as an update for Fedora 20. https://admin.fedoraproject.org/updates/dnf-0.4.10-1.fc20
Package dnf-0.4.10-1.fc20: * should fix your issue, * was pushed to the Fedora 20 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing dnf-0.4.10-1.fc20' as soon as you are able to. Please go to the following url: https://admin.fedoraproject.org/updates/FEDORA-2014-0089/dnf-0.4.10-1.fc20 then log in and leave karma (feedback).
dnf-0.4.10-1.fc20 has been pushed to the Fedora 20 stable repository. If problems still persist, please make note of it in this bug report.