I am trying Apply Quota Patch To Postfix i have build postfix.spec file in SPEC folder but when i used to build the spec file : # rpmbuild -ba postfix.spec libdb-devel is needed by postfix-2:2.9.2-2.el6.x86_64 systemd-units is needed by postfix-2:2.9.2-2.el6.x86_64 i am unable to install these packages via yum, i have removed db4-devel rpm because libdb-devel conflicts with db4-devel . but i am unable to install libdb-devel and systemd-units. i use : yum install libdb-devel systemd-units. it says no package found I am using local repository and epel repository , i have installed all Development tools but unable to install Development libraries at starting. please help how to install both the packages. I am following http://www.howtoforge.com/virtual-u...urier-mysql-and-squirrelmail-fedora-17-x86_64. To build a mail server.