Just a quick snippet of my /etc/yum.conf file which includes the ATrpms and FreshRpms repositories.

[main]
cachedir=/var/cache/yum
keepcache=0
debuglevel=2
logfile=/var/log/yum.log
pkgpolicy=newest
distroverpkg=redhat-release
tolerant=1
exactarch=1
obsoletes=1
gpgcheck=1
plugins=1
metadata_expire=1800

[atrpms]
name=Fedora Core $releasever – $basearch – ATrpms
baseurl=http://dl.atrpms.net/fc$releasever-$basearch/atrpms/stable

[freshrpms]
name=Fedora Linux $releasever – $basearch – freshrpms
baseurl=http://ayo.freshrpms.net/fedora/linux/$releasever/$basearch/freshrpms

A quick bit of shell magic to empty a Trac wiki database in a freshly installed Trac environment. In this example /var/www/html/trac is assumed to be the Trac environment you created with trac-admin.

$ for page in `trac-admin /var/www/html/trac wiki list | cut -d' ' -f1 | grep "^[A-Z]" | grep -v "Title"`; do trac-admin /var/www/html/trac wiki remove $page; done;