how to install rrdtool

[root@localhost jason]# rpm -ivh rpmforge-release-0.3.6.1.el5.rf.i386.rpm error: open of rpmforge-release-0.3.6.1.el5.rf.i386.rpm failed: No such file or directory [root@localhost jason]# rpm -ivh rpmforge-release-0.3.6.1.el5.rf.i386.rpm error: open of rpmforge-release-0.3.6.1.el5.rf.i386.rpm failed: No such file or directory [root@localhost jason]# rpm -ivh rpmforge-release-0.3.6-1.el5.rf.i386.rpm warning: rpmforge-release-0.3.6-1.el5.rf.i386.rpm: Header V3 DSA signature: NOKEY, key ID 6b8d79e6 Preparing... ########################################### [100%] 1:rpmforge-release ########################################### [100%] [root@localhost jason]# yum install rrdtool Loaded plugins: fastestmirror, priorities Loading mirror speeds from cached hostfile * base: ftp.daum.net * extras: ftp.daum.net * rpmforge: ftp.riken.jp * updates: ftp.daum.net http://apt.sw.be/redhat/el5/en/%24baserch/dag/repodata/repomd.xml: [Errno 14] HTTP Error 404: Not Found Trying other mirror. Error: Cannot retrieve repository metadata (repomd.xml) for repository: dag. Please verify its path and try again