Aug 212012
 

This is an article of mine, first published on Wazi

Every organization must monitor its infrastructure’s uptime and performance. While the popular Nagios application is a good general-purpose monitoring program that you can extend with plugins to handle just about any task, you may do even better by employing Cacti as a graphical front end to RRDTool‘s data logging and graphing functionality. Cacti was developed specifically to monitor and collect performance information, while Nagios is more oriented toward state changes, such as noting whether a daemon is up or down.

RRDTool stores all of the necessary information to create graphs and populate them with data in a MySQL database. Cacti provides templates to gather and show information such as system load (CPU, RAM, disks), users connected, MySQL load, and Apache load, all of which can affect the performance of your site.

Cacti’s front end is completely PHP-driven. It supports data gathering via different methods such as scripts in any language and SNMP.

Continue reading »

flattr this!

Apr 152012
 

Monitoring how much bandwidth is used is a fundamental task to check the status of your servers, or just your desktop, so i always test new tools to see if i find something good. This is the third article of this series and in this one i’ll take a look at Bmon, speedometer and Nload.

Continue reading »

flattr this!

Mar 222012
 

This is an article of mine, first published on Wazi
You can read the first part here

In this article we’ll see how apply BPF filters to wireshark to show the details of an HTTP session, an e-mail session and how to monitor who is visiting a certain site from our local network.
Finally I will make a summary of the most useful filters to use with Wireshark.

Here’s another classic example – an HTTP session. As before, start Wireshark and start capturing the traffic from the interface that goes out. Today, most HTTP traffic is compressed to speed up the exchange of information, so by default Wireshark decompresses the body part of HTTP packets. You can click on Edit -> Preferences -> Protocols -> HTTP and verify that “Uncompress entity bodies” is checked.
Continue reading »

flattr this!

Manage your bandwidth with Trickle

Sometimes it’s useful to limit the bandwidth used by some of your programs, perhaps you want to limit your Browser or FTP client, and they dont’ have a native way to limit the input and/or output bandwidth they are using, there is a small application that can solve this problem for you: Trickle trickle is [...]

Simple security by evaluating open ports

Article by Dominique Cimafranca first published on his blog regarding Ubuntu, and Linux in general. A simple but effective procedure for evaluating security on your computer is to check what sites it’s connecting to, or what sites are connecting to it. Most critical malware nowadays turn computers into zombies for botnets — typically zombified hosts will [...]