Measure the transaction response times of web and application servers. Performing continuous passive monitoring of network traffic. Recording historical data of measurements in a back-end database and presenting via a web front-end.
PasTmon is a passive network traffic analyzer that can measure user transaction response times of various application protocols. You can even define your own signature rules to monitor custom TCP based applications. PasTmon is a server administrator's tool for measuring application performance and response times.
PasTmon is Open Source and licensed under the GNU General Public License v3. It is available for Linux, free to download, use and tailor to your needs.
Highlights in 0.17:

  • Auto reconfigure as network interfaces are added or deleted, starting and stopping sensors accordingly. To support highly dynamic environments like OpenStack and CoreOS.
  • New docker images released on DockerHub pastmonweb, pastmonsensor.

"PasTmon Passive Application Response Time Monitoring a CoreOS Cluster"
- ReapingZombies4FunAndProfit Blog

"Keeping an eye on your network with PasTmon"
by Ben Martin at

"Application Performance Monitoring with PasTmon"
by Kerry Thompson originally published in SysAdmin Magazine July 2007.