Installing Munin, the site monitor named after a Norse god's crow

sudo aptitude install munin-node

sudo aptitude install munin 

sudo vi /etc/munin/munin.conf

a simple host tree

[wsf.grassrootsconnection.org]
address 127.0.0.1
use_node_name yes

Skipping this for now -- and I think this assumes both munin and munin-node on one server:

As a security measure, we are going to change so the node bind itself to the loopback interface.
So go and edit /etc/munin/munin-node.conf and make sure the host value looks like this:

#host *
host 127.0.0.1

sudo vi /etc/apache2/sites-available/munin

ServerAdmin webmaster@localhost
ServerName munin.grassrootsconnection.org
DocumentRoot /var/www/munin

Options FollowSymLinks
AllowOverride None

LogLevel notice CustomLog /var/log/apache2/munin-access.log combined ErrorLog /var/log/apache2/munin-error.log
ServerSignature On

sudo a2ensite munin

test syntax:
sudo apache2ctl -t

reload (article used sudo /etc/init.d/apache2 force-reload, not sure why, Agaric's way is more... graceful):
sudo apache2ctl -k graceful

That seemed to work!

http://munin.grassrootsconnection.org/index.html

Lets add another site and server to monitor-- this time, a different server.

# aptitude install munin-node
# vi /etc/munin/munin-node.conf

Added near the bottom of the file munin-node.conf, under "#host_name localhost.localdomain":

host_name wsf2008.net

Added to the very bottom of the file the IP address of the munin server (as a silly regular expression, boo Net::Server):

allow ^66.135.41.18$

Acknowledge this fresh start:

# /etc/init.d/munin-node restart

# /usr/share/munin/munin-update  --force-root

http://munin.grassrootsconnection.org/grassrootsconnection.org/wsf.grassrootsconnection.org.html

References:
http://www.debuntu.org/how-to-monitoring-a-server-with-munin
http://www.debianhelp.co.uk/munin.htm
http://2bits.com/articles/php-op-code-caches-accelerators-a-must-for-a-large-site.html

Resolution