when i tried to update a new install;

~]$ sudo yum -y update Loaded plugins: fastestmirror, refresh-packagekit, security Setting up Update Process Determining fastest mirrors * base: repos.dfw.quadranet.com * extras: repos.dfw.quadranet.com * updates: repos.dfw.quadranet.com extras | 3.4 kB 00:00 extras/primary_db | 37 kB 00:00 updates | 3.4 kB 00:00 updates/primary_db | 3.7 MB 00:02 Error: database disk image is malformed ~]$

ran a web search, which produced 'about 408 results'. skimmed thru them looking for a favorable url, which was;

forums.fedoraforum.org/showthread.php?t=308521

which led to these 2;

~]$ sudo yum clean dbcache ~]$ sudo yum history new

system is now updateing without errors.

hope this is help to anyone who man have problem.