Hello Mark 
You wrote:
I have created two files:
muninnode
which contains:
service[Munin]=x,x,x,/etc/init.d/munin-node restart,munin-node,root
This is mostly correct, however the following line will need to be adjusted:
Code:
service[Munin]=x,x,x,/etc/init.d/munin-node restart,munin-node,root
TO
Code:
service[muninnode]=x,x,x,/etc/init.d/munin-node restart,munin-node,root
The service name needs to match the name of the file that you created in the /etc/chkserv.d directory. Once you have made the change, you can monitor the results in the Chkservd log:
/var/log/chkservd.log
Thank you