Install through yum:

[root@system ~]# yum -y install rrdtool

Install through apt-get:

[root@system ~]# apt-get install rrdtool

For manual installation:

Download the .rpm or .deb file(s) and save it to disk.
Binary Distributions: http://oss.oetiker.ch/rrdtool/download.en.html

Install:

[root@system ~]# rpm -ivh rrdtool-<version>.rpm

or

[root@system ~]# dpkg -i rrdtool-<version>.deb