Munin-node is not available per default on RHEL6 servers. But luckily, somebody has made a mirror which contains many nice applications, including the munin packages we want.
rpm -Uvh http://ftp.uninett.no/linux/epel/6/x86_64/epel-release-6-8.noarch.rpm
yum install perl-XML-SAX
yum install munin-node
And voila! 🙂
perl-XML-SAX has to be installed first due to dependency issues.
Edited 7.march 2013, updated URL`s