Hi, perhaps this happens due to some oddity in my system, but I have noticed meesages like this while doing updates via yum (this has happened today)

Downloading packages:
updates/21/x86_64/prestodelta                               | 621 kB  00:00    
Delta RPMs reduced 21 M of updates to 1.4 M (93% saved)
(1/13): gdal-libs-1.11.1-4.fc21_1.11.1-5.fc21.x86_64.drpm   | 463 kB  00:00    
(2/13): gdal-python-1.11.1-4.fc21_1.11.1-5.fc21.x86_64.drpm |  42 kB  00:00    
(3/13): glpk-4.53-5.fc21_4.53-6.fc21.x86_64.drpm            |  87 kB  00:00    
(4/13): harfbuzz-0.9.35-1.fc21_0.9.36-1.fc21.i686.drpm      |  40 kB  00:00    
(5/13): harfbuzz-0.9.35-1.fc21_0.9.36-1.fc21.x86_64.drpm    |  41 kB  00:00    
(6/13): harfbuzz-icu-0.9.35-1.fc21_0.9.36-1.fc21.x86_64.drp |  11 kB  00:00    
(7/13): libgeotiff-1.2.5-16.fc21_1.4.0-2.fc21.x86_64.drpm   | 323 kB  00:00    
(8/13): phonon-4.8.1-1.fc21_4.8.2-1.fc21.x86_64.drpm        |  49 kB  00:00    
(9/13): qt5-qtlocation-5.4.0-1.fc21_5.4.0-2.fc21.x86_64.drp |  71 kB  00:00    
(10/13): qt5-qtsensors-5.4.0-1.fc21_5.4.0-2.fc21.x86_64.drp |  22 kB  00:00    
(11/13): stoken-libs-0.8-2.git.ba44603.fc21_0.81-1.fc21.x86 |  21 kB  00:00    
(12/13): wireshark-1.12.2-1.fc21_1.12.2-2.fc21.x86_64.drpm  | 271 kB  00:00    
(13/13): wireshark-gnome-1.12.2-2.fc21.x86_64.rpm           | 1.0 MB  00:00    
Finishing delta rebuilds of 10 package(s) (20 M)
/usr/sbin/prelink: No such file or directory
prelink not installed, cannot undo prelinking/usr/sbin/prelink: No such file or directory
prelink not installed, cannot undo prelinking/usr/sbin/prelink: No such file or directory
prelink not installed, cannot undo prelinking/usr/sbin/prelink: No such file or directory
/usr/sbin/prelink: No such file or directory     ]  0.0 B/s | 1.9 MB  --:-- ETA
Some delta RPMs failed to download or rebuild. Retrying../s |  20 MB  00:00 ETA
(1/5): harfbuzz-0.9.36-1.fc21.i686.rpm                      | 164 kB  00:00    
(2/5): harfbuzz-0.9.36-1.fc21.x86_64.rpm                    | 160 kB  00:00    
(3/5): harfbuzz-icu-0.9.36-1.fc21.x86_64.rpm                |  17 kB  00:00    
(4/5): libgeotiff-1.4.0-2.fc21.x86_64.rpm                   | 716 kB  00:00    
(5/5): stoken-libs-0.81-1.fc21.x86_64.rpm                   |  43 kB  00:00

So it seems that the reconstruction of certain packages fails due to prelink missing?

Regards, Sergio