Sniffit 0.3.7beta – Very good packet sniffer for unix. Has an interactive mode where you can select connections in progress to watch, or a mode to log packets to a file in the background. Supports a configuration file and tpcdump like packet filtering. Sniffit runs on LINUX, SunOS, Solaris, FreeBSD and IRIX.
You can download it from the following link: https://packetstormsecurity.com/files/download/10074/sniffit.0.3.7.beta.tar.gz
Source: https://packetstormsecurity.com/files/10074/sniffit.0.3.7.beta.tar.gz.html