Hi

On Sun, Dec 14, 2014 at 5:17 AM, Sudhir Khanger  wrote:
 DNF
regularly downloads cache, disables delta RPM support, and doesn't support
local repos. 

With the latest dnf update, Delta RPM support is enabled again.  

https://admin.fedoraproject.org/updates/dnf-0.6.3-2.fc21,dnf-plugins-core-0.1.4-1.fc21,hawkey-0.5.2-1.fc21

As a general recommendation, always refer to specific bug reports when talking about issues

Rahul