[rrdtool] how to install rrdtool on CentOS 5.X 64bit

1. add Dag RPM Repository

# vi /etc/yum.repos.d/Dag.repo

-----------------------------------

[dag]

name=Dag RPM Repository for Red Hat Enterprise Linux

baseurl=http://apt.sw.be/redhat/el$releasever/en/$basearch/dag

gpgcheck=0

enabled=1

protetc=0

-----------------------------------

2. install rrdtool

# yum install rrdtool