https://fedoraproject.org/wiki/Upgrading_Fedora_using_package_manager
の 'Fedora 22 -> Fedora 23'
# rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-fedora-23-$(uname -i) # dnf upgrade # dnf clean all # dnf --releasever=23 --setopt=deltarpm=false distro-sync
に従ってアップグレード。