Installing Cacti in CentOS 6.2 Part 2: GUI, Plugins, Host Monitoring, Email Alerts

First thing your going to do since the last post is log into the fresh cacti server.
This can be achieved by going to http://(serverIP or FQDN)/cacti
From here, you will get the welcome/setup screen:

This just gives you some basic info that will help you understand what you are about to do.

Just press next here, of course you want to pray to the GNU gods and thank them for the wonderful open source movement. Sacrifice a small microchip here for extra blessing.



A few screens later I got a list of things that ARENT installed on my cacti installation.
Looks like im missing

So we want to install these. Hop into the CLI of the server and run this command:

#>   yum install net-snmp net-snmp-utils
#>  echo “[dag] name=Dag RPM Repository for Red Hat Enterprise Linux baseurl=\$releasever/en/\$basearch/dag
enabled=1″ > /etc/yum.repos.d/dag.repo
#>  yum install rrdtool

This will get the right things installed, you can now refresh the page to see that all the expected binaries are installed.

Next, it will bring you to the familiar login screen where the default u/p is ‘admin/admin’ It will ask you to change your password for the admin user on first entry.

then we are in the main menu!

You can even see your current installed version in the top right. At the time of this writing, version 0.8.8a was the latest.



My base installation has three plugins installed:

Thold – build threshholds and gain email alerts based on them
Syslog – receive input from syslog and display it in cacti
Settings – a general settings plugin for cacti

Installing plugins is actually pretty easy. You just wget them, untar them and copy them into the right dir on the cacti install. Lets get started!
First, you need the path for the tarballs, head to and find the appropriate plugin and find the path.
input that path after the wget command. I usually just wget these to my home folder and then extract/copy them out. But you can do what you want.


It drives me crazy, but the plugins have a : in their name, so when you get it downloaded, you have to rename them in order for tar to not freak out.

 mv plugin:thold-v0.4.9-3.tgz thold.tgz

now with the file in a doable format, find the freedom to untar that business and then copy it to the right place in the cacti/plugins dir.

tar -zxvf settings.tgz
tar -zxvf thold.tgz
tar -zxvf syslog.tgz
rm -Rf *.tgz
mv ./settings /var/www/html/cacti/plugins
mv ./syslog /var/www/html/cacti/plugins
mv ./thold /var/www/html/cacti/plugins

if you are unsure of where cacti is installed, you can always run

find / -name cacti

this will search root and get your cacti installation visible in the output.

Now that the plugins are moved to the right folder, head to the plugins page in the cacti web interface and refresh, you’ll see the plugins now listed. Easy? thanks to the PIA (plug in architecture) that the developers created. Small sacrifice to GNU required at this point.

Install the plugin with the nice little buttons.
You’ll get some questions when installing syslog, and for us, since we’ve got nice versions, we install with the partitioned and nice db options.

Now is a good time to head over to the settings page and make configurations for your setup.
I wont cover all the options, as they will be specific to your needs and emotional connectedness to your current shop.


Next well get some common things in place to make adding hosts really easy, and make sure that you are tracking the right things.
My favorite thing to track Windows hosts with is SNMP-Informant. It installs a small service on a windows machine and will track OIDs. I love it. They have a standard version that you can play around with as long as your a small shop.

Once you have configured your host to accept SNMP from the cacti machine, you can look at all sorts of wonderful data.
The cacti forums have tons of great Data Queries that you import into cacti and then build out monitoring from there.

Thold is one of those that can do wonderful email alerts if a SNMP query has passed a certain limit, or if a host goes down.


I wont get into data queries here, as they each have their own way of installing and configuring.
Enjoy Cacti.