Sunday, June 8, 2014

Cacti - Let's Dance.

Ok - for a really long time people have been carrying on about Open Source network monitoring and how good it is bla bla bla.

Well, I've been around long enough to see that while Open Source apps have their place in an FCAPS management platform, there isn't an Open Source app that ticks all these boxes (ESPECIALLY from a network perspective).

Once you start digging, you'll notice that most Open Source "Network" monitoring and management apps should REALLY be called "Server" monitoring and management apps.

It really does shit me to tears how often the word "Network" is used to incorrectly describe anything else (servers, workstations, end user devices) simply because they connect to a network.

While there are a number of good commercial Network management applications out there (HP IMC, a handful from Manage Engine) and some bad ones (Cisco PRIME)...

Anyway, todays focus is on Cacti.

Cacti itself is a great graphing tool which is basically a modern day version of the venerable MRTG.

Cacti has one awesome feature though which is plugin support.

Add some plugins and all of a sudden you've got yourself threshold monitoring and alerting, live bandwidth monitoring and all sorts of goodness.

Now, Cacti is a bit of a bitch to install.

Thankfully, there's a really good guide / script that covers how to install cacti with all useful plugins over at:

I used to have a modified version of the above links script in this post but honestly, save yourself a lot of time and pain and just download CactiEZ.

CactiEZ is a pre-rolled ISO where you basically install it on a VM, set a password and IP address, choose which plugins you wish to enable through the GUI and you're up and going.

I have Cacti running in a commercial environment running from the Cacti EZ installer and it just works.

In fact, it does everything our previous installation of PRTG did but has even more features.

Installation is a breeze.

Once you're at the first-time configuration GUI, my advice is to check all add-ons and plug-ins (except the Barracuda device plug-in unless you have a specific need for this) even if you don't need them straight away.

Now, before you start adding devices, here's a hot tip - CactiEZ has 1 minute averages configured out of the box.

Those who want / need this understand how important that is.

To enable 1 minute average reporting go to Console -> Templates -> Data Templates and select Interface - Traffic.

In the associated RRA's list select all and click save.

Now, speaking of adding devices, Cacti has an auto subnet discover feature (although it's somewhat hidden).

To enable it, go to Console -> Configuration -> Settings -> Misc and perform the following:

Under Discover -> Subnets to Scan enter your subnet information.
Next, configure your SNMP Communities string to the read-only string you've configured campus wide (right?) and set the discovery schedule to your desired interval.

Newly discovered devices will appear in the Devices area which you can then filter and begin monitoring.

No comments:

Post a Comment