How to make local rpm source in CentOS

yum install createrepo

cd /opt/yliyun/conf
createrepo ./rpm

/opt/yliyun/conf/CentOS-Local.repo
# CentOS-Local.repo
#
#  This repo can be used with mounted DVD media, verify the mount point for
#  CentOS-6.  You can use this repo and yum to install items directly off the
#  DVD ISO that we release.
#
# To use this repo, put in your DVD and use it with the other repos too:
#  yum --enablerepo=c6-local [command]
#  
# or for ONLY the media repo, do this:
#
#  yum --disablerepo=\* --enablerepo=c6-local [command]
[c6-local]
name=CentOS-$releasever - Media
baseurl=file:///opt/yliyun/conf/rpm/
gpgcheck=0
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6

yum --disablerepo=\* --enablerepo=c6-local -c conf/CentOS-Local.repo -q -y localinstall conf/rpm/*.rpm --nogpgcheck