Having given up on installing and using Munin once already I thought I would jot a few notes to help in future troubleshooting.
 
								- Test the connection by telnet from the munin-server to the munin-node
 telnet mynode 4949
 list [you should get a list of services available]
 fetch vmstat [you should get some vmstat numbers]
- Firewall is the munin-node firewalling the connection attempts of the munin server? Check iptables or system-security-tui
- host_name If you do not get any graphs check that munin-node.conf host_name value is set to the value that appears when telneting to port 4949 e.g.
 # munin node at my-server.tld
- Permissions There is probably an easier way to do this but I changed the munin users shell to bash temporarily and su – munin, then I ran the cron job and discovered some permission problems probably caused by something I did earlier. After fixing these I changed the shell back again to nologin and allowed the cron job to run and this sorted some of my graphing problems.
- Centos 5 – PNG Graphs not being produced from the rrd output. I tried to force running as root (not generally advised) 
 /usr/share/munin/munin-graph –force-root and got a font error: No fonts found; this probably means that the fontconfig 
 library is not correctly configured. You may need to
 edit the fonts.conf configuration file. More information
 about fontconfig can be found in the fontconfig(3) manual
 page and on http://fontconfig.orgThe solution seems to be to rollback your rrdtool from version 1.3.7 to 1.2.30 
 rpm -e –nodeps rrdtool
 wget ftp://fr2.rpmfind.net/linux/dag/redhat/el5/en/i386/dag/RPMS/rrdtool-1.2.30-1.el5.rf.i386.rpm
 yum install libart_lgpl
 rpm -Uvh rrdtool-1.2.30-1.el5.rf.i386.rpm


