Munin

Added by Michael Magua

What is Munin?

Read here: http://munin.projects.linpro.no/

Also on howtoforge: http://www.howtoforge.com/monitoring-multiple-systems-with-munin-debian-...

Packages:

(This is built around RHEL 4u4 done on Hulk - Regent Insurance)

I used the Dag Repo. Depending on your configuration you'll probably want these packages:

munin

munin-node

perl-Crypt-DES

perl-Digest-HMAC

perl-Digest-SHA1

perl-HTML-Template

perl-Net-Server

perl-Net-SNMP

perl-Socket6

Server configuration:

Config directory: /etc/munin

Open /etc/munin/munin.conf

Configure the default host/tree which is the server:

[server1.domain.com]

address 127.0.0.1

use_node_name yes

Edit /etc/munin/munin-node.conf and uncomment the host stanza and add your hostname, i.e:

host_name server1.domain.com

Upon installation the checks have been added to /etc/cron.d/munin. Edit this file to have it poll your

nodes as often as you desire. The default is 5 minutes.

Start munin-node service locally:

chkconfig --levels 3 munin-node on

/etc/init.d/httpd restart

/etc/init.d/munin-node start

chown -R munin.munin /var/www/html/munin

At this point you can browse http://localhost/munin/ to see your new graphs.

Packages:

Install the same packages as the server except for munin itself. Since it is a node you will need

munin-node.

Node configuration:

Config directory: /etc/munin

Edit /etc/munin/munin-node.conf to suit your needs, i.e for a node with an ip of 192.168.1.2 with

hostname of server2.example.com:

# Which port to bind to;

host 192.168.1.254

Edit /etc/munin/munin-node and uncomment the host stanza and add your hostname, i.e:

host_name server2.example.com

Add a munin server that you trust to the bottom of the file to do the checks, i.e if the munin server has

an IP of 192.168.1.1:

allow ^192\.168\.1\.1$

Start the munin-node service:

chkconfig --levels 3 munin-node on

/etc/init.d/munin-node start

Munin-node listens on tcp/4949 incase you're running iptables.

iptables -I INPUT -s -p tcp -m tcp --dport 4949 -j ACCEPT

Edit /etc/munin/munin.conf and underneath your host/tree add the node, i.e for node above:

[server2.example.com]

address 192.168.1.2

Q)How do the plugins work?

A)The plugins in /etc/munin/plugins are just symlinks to /usr/share/munin/plugins/*

Q)How do I enable a new plugin?

A) cd /etc/munin/plugins/ && ln -s /usr/share/munin/plugins/plugin . && /etc/init.d/munin-node restart

Q)How do I disable a plugin?

A)cd /etc/munin/plugins && rm -f && /etc/init.d/munin-node restart

Q)I have no graphs?

A)Have you got rrdtool / perl-rrdtool installed?

Q)Where can I get more plugins?

A)http://muninexchange.projects.linpro.no

Q)I've downloaded a new plugin what now?

A)mv plugin /etc/munin/plugins && /etc/init.d/munin-node restart

You can view a demo on Hulk at Regent by doing (enter the synaq password for Batman):

ssh -L 1234:172.20.85.217:80 synaq@196.15.172.233

Browse to http://localhost:1234/munin/