Netkit is a self-contained environment that makes it easy and costless to
emulate complex network configurations on a single host machine. The idea
underlying Netkit is that each network device is implemented by a virtual
machine running the appropriate software. Virtual machines can then be
interconnected as desired by configuring virtual collision domains.

Interconnected machines may be organized to form a laboratory (lab),
which can be used to emulate the behavior of a particular service or
protocol (e.g., DNS). The configuration of the lab can be saved to ease
its distribution and replication.

The project was born (and is still carried on) with the main purpose of
supporting teaching of networking subjects with realistic experiences.

Requires netkit-kernel and netkit-filesystem available at SlackBuilds.org

After installing add environment variable to ~/.bashrc (~/bash_profile)
or system global:

export NETKIT_HOME=/opt/netkit export MANPATH=:$NETKIT_HOME/man export
PATH=$NETKIT_HOME/bin:$PATH

You may check your configuration:

# cd /opt/netkit # ./check_configuration.sh

For quick start:
http://www.netkit.org/netkit-labs/netkit_introduction/netkit-introduction.pdf
http://www.netkit.org/faq.html