yum verify

[Bruno Wolff III]

On Sat, Jul 25, 2009 at 20:54:56 +0100,
  Patrick Dupre <pd520 at york.ac.uk> wrote:
> Hello,
>
> I would like to check the integrety of my installation. Is their an
> option of yum which could let me check all the packages and download
> the one which are not correct ?
>
> rpm let me verify, but not download.

You can use yum reinstall to reinstall the packages flagged by rpm.
You can use the whatprovides query option to get from files to packages.