How to run X applications on a guest VM in the cloonix network simulator

To run a program that uses a graphical user interface on a guest virtual machine running in the cloonix open-source network simulator, log into the guest VM from the host computer using SSH and forward the X11 display. Then, any X11 program you run on the guest VM using that SSH session, such as Wireshark, will display its X windows on the host computer.

Initial setup

First, we create a cloonix network simulation with at least one guest VM. In this example, we created three guest VMs named Cloon1, Cloon2, and Cloon3.

A cloonix network simulation with three guest VMs

See previous posts related to using cloonix, if you need help setting up the example network.

Connect to guest VM via SSH

Open a new terminal window on the host computer. We do this so we can run X windows from the guests on the host. As discussed in the Cloonix v24 overview post, cloonix uses a patched version of the Dropbear SSH client so we use the dbssh command that is installed in the cloonix tree directory, ~/Netsims/cloonix-24.11.

The Dropbear SSH client automatically forwards X windows from the client machine to the server machine so Continue reading

How to simulate an IPv6 network using the cloonix network simulator

As we work through this tutorial, we will learn how to use the cloonix graph interface to build a simulation scenario that includes two small IPv6 networks connected to each other by two routers via static routes. We will also learn how cloonix saves network topologies and guest virtual machine root filesystems.

Linux IPv6 network simulation running on the cloonix open-source network simulator

The cloonix open-source network simulator uses KVM virtual machines in the simulated network so, in this tutorial, we will demonstrate real Linux router and host configuration procedures.

Procedure summary

First, let’s review the high-level steps we will execute to set up and configure a simulated IPv6 network and then save a network topology and node configurations.

1. Create root filesystems, one for each virtual machine we plan to create in the simulation
2. Create static guest virtual machines with the previously-created root filesystems
3. Connect nodes to create a network topology
4. Configure each node in the simulated network
5. Save the network simulation scenario for future use
6. (Optional) Make changes and save another version of the topology
7. (Optional) Load a saved network simulation scenario

Step 1: Create root filesystems

We intend to create a scenario made up of static root filesystems Continue reading