rar'I yüklemeniz gerekiyor.

32bit için :
wget http://packages.sw.be/rpmforge-release/rpmforge-release-0.5.1-1.el5.rf.i386.rpm

rpm -ivh rpmforge-release-0.5.1-1.el5.rf.i386.rpm
64 bit için
wget http://packages.sw.be/rpmforge-release/rpmforge-release-0.5.1-1.el5.rf.x86_64.rpm

rpm -ivh rpmforge-release-0.5.1-1.el5.rf.x86_64.rpm
ardından

yum -y install rar unrar