Cacti is a free network monitoring and graphing (”trending”) tool, which i’ve managed to install on a computer at work. The idea is that eventually i will have a portable network monitoring tool that is both easy to physically lug around and reasonably easy to plug into a new network and let it do its thing. Eventually, there will be more tools installed. While the solution presented here is really simple, i did four complete re-installs of the system before i was up and running. I could have made it with less work if i’d either followed the kind instructions given, or if i’d spent more time debugging. This time i just took the lazier path. These are the steps i took:

• Install Kubuntu 7.10 (which is the current stable version — the new one’s out in twenty odd days). While any Linux installation will do, these instructions are for a Debian-based distribution… which includes the aptitude application. If you don’t have aptitude, just use whatever package management system may you have. When you’re done, reboot.
• Optional, but recommended: Using Adept, or any other package management tool of your choice (use apt-get, if everything else fails), remove the packages you don’t need. I removed the office and multimedia packages, since this won’t be a desktop/office station.
• Optional: Add proprietary display driver, in my case, the NVidia driver. REBOOT once you’re done, or start from step one above.

Now it’s time to update your system. I first did this using the graphical Adept tool, but it crashed on me, so i moved to the command line instead.

• Fire up a terminal (i use konsole) and enter sudo aptitude update. You will be prompted for your password. Watch the texts fly.
• Next, enter the following two lines:
  sudo aptitude safe-upgrade
  sudo dpkg –configure -a
  Repeat until you get no errors

Your computer is now updated. Time to add Cacti. Cacti needs MySQL to be installed first, and while the cacti package suggests that it will install MySQL properly, it won’t. At least not yet. A future version probably will. Again at the terminal (konsole), enter the following and answer Yes to any questions.

• sudo aptitude install mysql-server
• sudo aptitude install cacti

The installers will ask for the passwords for mysql administration and the cacti application. Depending on the context, you will create one or recall it. In either case, write that password down, because once you need it, you won’t remember it

The Cacti installation will use the Apache 2 web server, but i had a problem with the Cacti installation that needed to be (located, debugged and) fixed first:

Edit the /etc/apache2/conf.d/cacti.conf file. On the first line of the file, change the Alias /cacti into Alias /cacti/site. Leave the path at the end of the line untouched.

I know i’m probably doing something fundamentally wrong here, as Cacti should be running from the aliased directory /cacti, not /cacti/site, but applying this fix made Cacti run for me.

Now fire up a web browser on your monitoring box and go to http://localhost/cacti/site to access your Cacti installation. If all goes well, log in as admin/admin, change your password and (with the help of the Cacti manual) start adding devices!