OpenStack on one machine
To learn more about OpenStack cloud management software, a student or research may install OpenStack on a single machine, such as a laptop computer or a virtual machine, and emulate a small datacenter using virtual machines or containers.
Researchers and students may choose from multiple projects that will set up OpenStack on a single machine. Some projects are community-based open-source projects and others are vendor supported projects (while still nominally open-source).
This post is an overview of links and resources to installing OpenStack on one machine.
DevStack
DevStack is a community-driven open-source project that provides scripts and drivers to install OpenStack on a single machine. It includes direction to install on a laptop computer and to install on a single virtual machine. Devstack may also be configured to use LXC containers as compute nodes, or to use nested KVM virtualization for compute nodes.
OpenStack AutoPilot
Openstack Autopilot is the Ubuntu OpenStack installer. It is free as long as you use less than ten machines in your cloud infrastructure. So, most students and researchers will be able to play around with Autopilot for free.
Autopilot will set up an OpenStack cloud using LXD containers. This means that the system can Continue reading
Using the OpenDaylight SDN Controller with the Mininet Network Emulator
OpenDaylight (ODL) is a popular open-source SDN controller framework. To learn more about OpenDaylight, it is helpful to use it to manage an emulated network of virtual switches and virtual hosts. Most people use the Mininet network emulator to create a virtual SDN network for OpenDaylight to control.
In this post, I will show how to set up OpenDaylight to control an emulated Mininet network using OpenFlow 1.3. Because I am using virtual machines, the procedure I use will work the same in all commonly used host systems: Linux, Windows, and Mac OS X.
Using Virtual Machines
In this lab example, I will use two virtual machines. One will run the Mininet emulated network and the other will run the OpenDaylight controller. I will connect both VMs to a host-only network so they can communicate with each other and with programs running on the host computer, such as ssh and the X11 client.
I will use VirtualBox to run the Mininet VM that I downloaded from the mininet project web site, which is the easiest way to experiment with Mininet. The Mininet project team provides an Ubuntu 14.04 LTS VM image with Mininet 2.2.1, Wireshark Continue reading
Saving a Cloonix network topology
The Cloonix network simulator has been updated to version 29, which adds the ability to save network simulation topologies and node configurations to a directory.
Users may save a network topology and all node configurations to a directory of their choice. They may also load saved topologies into Cloonix so they can restore a network scenario they previously created. The save function of Cloonix v29 supports copy-on-write filesystems and also allows users to save the full filesystems of nodes, if they wish.
This post will work through a detailed tutorial showing how to save, load, and re-save topologies and node configurations using the Cloonix GUI or command-line interface.
Different methods to save a Cloonix project
In this tutorial we will show three ways Cloonix may be used to save filesystems and network topologies:
- Create a new base filesystem by starting a VM in Cloonix, loading software and configurations, then saving either a full VM disk image or a derived VM disk image.
- This simple case is useful when upgrading or modifying disk images that will be used in simulation scenarios.
- This simple case is useful when upgrading or modifying disk images that will be used in simulation scenarios.
- Start the Cloonix graph, set up the VMs, load software, and configure them. Then save the topology and filesystems.
Lenovo Thinkpad T420: Another excellent, inexpensive Linux laptop
For the past three years, I have been using a Lenovo Thinkpad T400 as my main platform for researching open-source network simulators and emulators. The T400 is an excellent, inexpensive computer that, even today, offers excellent value.
But, I need a computer that supports high-resolution external monitors so it must have a DisplayPort output. I also want to expand the number of VMs I can run concurrently with adequate performance so I need a processor that supports HyperThreading. I want to switch to the Ubuntu Linux distribution and the Ubuntu Unity desktop environment needs just a bit more processing power to run smoothly.
I recently purchased a used Lenovo Thinkpad T420 laptop, which offers everything I want and more. It is a five-year old product but it offers all the ports and performance I need. Because it is well past its depreciation curve, anyone can purchase a used T420 for a very low price. Read on to learn more about the Lenovo Thinkpad T420, another excellent and inexpensive Linux platform.
The Lenovo Thinkpad T420
The Lenovo Thinkpad T420 is a business-class notebook produced in 2011 that was leased in large volumes by companies for use by their employees. Now, Continue reading
Process images for your blog with ImageMagick
When writing a blog post about a technical topic, I often capture a lot of screen shots that I need to edit before adding them to my blog article. Usually I want to add a border around each image and I sometimes want to reduce the size of images that are too large. I want to do this quickly and easily so I use ImageMagick, an open-source command line image editor.
It takes too long to edit a large number of images one by one in an image editor like Photoshop or Gimp. Using ImageMagick makes it easy to batch process all images in a folder by entering a simple command. You may also incorporate ImageMagick into shell scripts, batch files, or other programs to automate the preparation of images for your blog.
ImageMagick is a powerful image manipulation tool with an intimidating set of options and subcommands. However, most bloggers will use only a few simple options. In this post, I will show how to install and use ImageMagick to perform the simple image conversions bloggers typically need. I will show how this can be done on each of the major operating systems: Linux, Windows, and Mac OS X.
Continue reading
Cloonix Network Simulator updated to v28
The Cloonix development team recently released a major update to the Cloonix network simulator.
Cloonix version 28 makes major changes to the infrastructure of Cloonix. It changes the installation procedure, the location of Cloonix files on your computer, and the names of the commands used to start and administer Cloonix.
Cloonix version 28 also makes changes to the features available to users. It adds support for multiple Cloonix servers running on the same machine, and standardizes and documents the new interface types used to connect virtual machines to each other.
Read the rest of this post for more details about what’s new in Cloonix v28.
Using Cloonix
In this post, I wrote some examples to show how to use the changed features in Cloonix v28 but I will not discuss the basics of using Cloonix because I assume the reader is already familiar with Cloonix.
If you are not already familiar with Cloonix, you should read the Cloonix documentation. Also, I have written many posts about using the Cloonix network simulator. Please check these posts if you need more information about using Cloonix.
Install Cloonix
The procedure to install Cloonix v28 has changes slightly — one new software dependency has Continue reading
KVM Performance Limits for virtual CPU cores
When using open-source network simulators that use KVM as a virtualization tool, each node in the network simulation is actually a KVM virtual machine so the maximum supported number of nodes in a network simulation is the same as the maximum number of KVM virtual machines that can run on the host computer.
Unfortunately, there seems to be no single authoritative statement about the maximum number of KVM virtual machines that can run on a host computer. Most information I could find about KVM limits does not publish absolute limits but, instead, recommends best practices.
In this post, I will synthesize the information available from many different sources into a single recommendation for the maximum number of KVM-based nodes that can run in an open-source network simulator running on a single host computer.
Capture data on open-source router interfaces in GNS3
In this post, I will show how to set up data capture in the GNS3 network simulator when using network devices that are emulated by VirtualBox or QEMU virtual machines.
The GNS3 network simulator makes it easy for users to capture and view data passing across the interfaces of devices running in a GNS3 network simulation. The GNS3 documentation covers how to capture data from devices running on Dynamips in GNS3 but the procedures for capturing data from devices running in other hypervisors, such as VirtualBox or QEMU/KVM, are not well documented.
While GNS3 users may start and stop data capture on Dynamips VM interfaces any time they wish, they must plan ahead when they intend to capture data on open-source routers and hosts running on VirtualBox or QEMU virtual machines.
Using VirtualBox linked clones in the GNS3 network simulator
GNS3 1.3 will create and manage VirtualBox virtual machine linked clones from within the GNS3 user interface. This simplifies the process of setting up VirtualBox virtual machines in GNS3 makes GNS3 easier to use for studying the operation of open-source routers, switches, and hosts in network simulation scenarios.
In this post, I will show how to set up and use VirtualBox linked clones in your GNS3 simulation scenarios and work through a detailed tutorial.
Using POX components to create a software defined networking application
When network engineers are learning the concepts of software defined networking and SDN controllers, they may want to experiment with SDN network scenarios before learning to write programs to be used by the SDN controllers.
POX is a simple-to-use SDN controller that is bundled with the Mininet SDN network emulator and is used in education and research as a learning and prototyping tool. POX components are Python programs that implement networking functions and can be invoked when POX is started. POX comes with a few stock components ready to use.
In this tutorial, we will use stock POX components to implement basic switching functionality with loop prevention in a software defined network, without writing any code. Then, we will explore how the SDN controller programs the OpenFlow-enabled switched in a network created using the Mininet network emulator.
Prerequisite knowledge required
This tutorial assumes you already have the the prerequisite knowledge defined in the list below. If you need to understand more about any of the topics listed below, the list provides links to resources that offer enough information to prepare you to work through this tutorial.
- You have a basic understanding of Ethernet networks, IP networking, and software Continue reading
How to map OpenFlow switch TCP ports in Mininet SDN simulations
When testing SDN functions in the Mininet network emulator and viewing captured OpenFlow messages in a packet analyzer such as Wireshark, it is difficult to identify which SDN switch is the source or destination of each captured message.
The only reliable way to identify which SDN switch sent or received an OpenFlow message is to look at the source or destination TCP port of the OpenFlow packets. This is because most OpenFlow messages exchanged between switches and the controller do not contain any other information that helps identify the sending or receiving switch. Neither Mininet nor the Open vSwitch database provides information that might be used to identify the TCP ports used by each switches to communicate with the OpenFlow controller in the network.
This post describes a procedure to map which TCP ports are used on each switch to communicate with the SDN controller in the Mininet network simulation. This procedure will enable researchers or students to study the interactions between SDN controller and switches in a more detailed and accurate way.
Summary of procedure
To map which TCP ports are used on each switch to communicate with the SDN controller in the Mininet network simulation, execute the steps Continue reading
IMUNES on Linux
The IMUNES open-source network simulator can now be installed on and run on Linux. Previously, IMUNES was available only for the FreeBSD operating system.
The Linux version of IMUNES is ready to be used and can set up and run network emulation scenarios. It does not yet have all the features offered in the FreeBSD version of IMUNES but the development team intends make add in more features until both versions support similar capabilities.
In this post, we will show how to install the Linux version of IMUNES on Ubuntu 14.04, look at the tool set used by IMUNES on Linux, and experiment with a simple network simulation scenario.
Compatibility with Linux versions
IMUNES is compatible with all popular Linux distributions.
The IMUNES development team seems to be testing IMUNEs on the latest available Linux distributions. If you are using Linux distributions like Ubuntu 15.04, you can follow the standard IMUNES install directions. However, if you are using a long-term-supported distribution like Ubuntu 14.04, there are some extra software dependencies that you must install.
Install IMUNES in Ubuntu 14.04
I am using Ubuntu 14.04 LTS as my host operating system. When installing IMUNES on Ubuntu Continue reading
GNS3 Version 1.3: What’s new for Open-Source Routers
In 2014, the GNS3 development team launched a successful Kickstarter crowdfunding campaign to support development of a major new release, version 1.0, which was released in October that same year. I was happy to support the Kickstarter campaign and now I am finally getting around to taking a look at the new version of GNS3.
The last time I used the GNS3 network simulator, it was at version 0.8.7. After producing version GNS3 1.0, the GNS3 development team has been updating it frequently. GNS3 is now at version 1.3.7.
In this post, I will look at the new version 1.3.7 of GNS3 and evaluate how it works with emulated routers and hosts running open-source software.
What’s new in GNS3 1.x
Below, I describe the new GNS3 1.x features in two sections. The first section summarizes new GNS3 features that are relevant to all users of GNS3, including those who will use GNS3 to emulate networks consisting of routers and hosts running open-source software. The second section summarizes new features relevant only those who are running commercial router images in GNS3.
New features relevant to open-source routers
The following list Continue reading
Book review: The Book of GNS3
No Starch Press recently offered me a preview copy of a new book about the GNS3 network simulator, titled The Book of GNS3 written by Jason Neumann. This book covers the new version of GNS3, GNS3 1.x. Here is my review of The Book of GNS3.
The Book of GNS3 effectively serves as a user manual for GNS3. It offers detailed installation and configuration information for GNS3 1.x in one easy-to-access volume. Experienced users will find some new information in this book, especially about the new features available in GNS3 1.x. However, I think the main beneficiaries will be new or inexperienced users of GNS3.
GNS3 is usually used by people who wish to emulate networks of commercial routers from vendors such as Cisco and Juniper. Understandably, Mr. Neumann spends most of the book discussing how to set up GNS3 to run commercial routers and, as much as is possible, switches.
How does this book help those who want to use open-source routers in GNS3? Read the rest of my review to find out.
Coverage of Open-Source Routing topics
While I read through this book, I looked for the parts that are relevant to my interests in Continue reading
Install the GNS3 network simulator version 1.x
The GNS3 development team produced a major new release, version 1.0, in October 2014. Since then, they have been regularly updating GNS3 and, at the time I write this, the latest version of GNS3 is version 1.3.7.
The latest version of GNS3 cannot be installed using a package manager like Ubuntu Software Center or Synaptic because no packages have been created yet for GNS3 1.x. The Ubuntu repository and the GNS3 PPA only provide packages for old versions of GNS3. The latest version of the GNS3 package for Debian/Ubuntu is GNS3 0.8.7.
The GNS3 development team is working on packages for GNS3 1.x but, as of the time I post this, it is not clear when they will be available.
To install the latest version of GNS3 on an Ubuntu Linux system, install the dependencies, download the GNS3 source files, and compile the software. I provide the list of commands in this post.
Install GNS3 on Ubuntu Linux
We will use GNS3 to build a simulated network consisting of open-source routers, switches, and hosts so we only need to install the GNS3 GUI, the GNS3 Server, and VPCS. However, in the sections below, Continue reading
Build your own network simulator using open-source DevOps tools
Open-source DevOps tools are used to deploy applications and services in datacenter server networks, but they may also enable researchers or students to simulate networks. In this post, we will survey popular open-source DevOps tools and provide links to information that shows how to use them to create network simulation scenarios.
Most open-source network simulators simplify the setup and configuration of virtual machines and the networking connections between virtual machines. DevOps tools such as OpenStack do the same things, although they expose more of the complexities of the virtualized infrastructure to the user.
If you are already using DevOps tools for other activities you may find it useful to also use them when you need to create a simulated network instead of learning to use a network simulator.
Comparing simulators to DevOps tools
Both open-source network simulators and a coordinated set of DevOps tools perform the same role: they orchestrate the setup, interconnection, and configuration of virtual nodes in a virtual network.
Open-source simulators are built to support small-scale simulation scenarios on one computer, although some can run in a distributed mode across multiple computers. DevOps tools are designed to work in datacenters composed of hundred or thousands of servers, Continue reading
CORE Network Emulator updated to 4.8
The CORE Network Emulator has been updated to version 4.8. This new version fixes the issues I noted in my previous review of CORE release 4.7. It also implements some new features. See the CORE 4.8 release notes for all the details.
The most visible change is the addition of some new services — most notably a new Docker service that will allow Docker containers to be used as nodes in the simulation scenario.
More about CORE
I’ve written a lot about the CORE Network Emulator and all my previous posts are still relevant to CORE 4.8 — except where I discuss the bugs in previous versions that are fixed in the latest release. If you have not used the CORE Network Emulator before, I suggest you read the following posts, in order:
- CORE Network Emulator overview
- Solving a few issues
- Install services software
- Solve the garbage-data problem
- New features in CORE 4.7
- Services Overview
- How to customize services
This should get you started using the CORE Network Emulator. If you wish to learn more, please read my other posts about CORE and consult the CORE documentation.
Install CORE 4.8 from packages
One can Continue reading
Cloonix network simulator updated to version 26
The Cloonix development team released an update to Cloonix version 26 in May 2015. An important addition in version 26 is a greatly expanded and improved Cloonix user guide.
The new version also changes the user interface, adds a new LAN type, and eliminates the t2t device. It also includes updated guest virtual machines.
User interface changes
In Cloonix Version 26, the user interface eliminates the tool bar and makes all graph objects available via a right-click drop-down menu.
Right-click to access the virtual network object menu
Cloonix v26 KVM configuration window
Installing Cloonix v26
The only change to the install procedure is a some new prerequisite software packages that must be installed to support compilation.
You can install pre-compiled binaries or compile Cloonix from source code. I prefer to compile it. The source code and the precompiled binaries are on the Cloonix Software page.
To compile the source code on Xubuntu 14.04, I followed the procedure documented in the Cloonix install documentation.
We will install Cloonix v26 in our Home directory. Download and unpack the source code.
Visualizing software defined network topologies using POX and Gephi
When a researcher uses the Mininet network simulator to create a network of hosts and switches connected to an SDN controller, he or she may wish to be able to see what the simulated network topology looks like.
The POX SDN controller includes a component that will send network topology data to the Gephi data visualization platform, which can the show a graph of nodes and links representing the network topology. In this post, I will show how to set up POX and Gephi so we can see the network topologies created using the topology options in the Mininet command.
While we work through this tutorial we will also see how the POX SDN controller, which does not offer a native Northbound API, can use POX components to provide northbound interfaces.
Prerequisite skills and activities
This tutorial assumes you already have the following. I include links to relevant posts if you need to review any of these requirements.
- You have a basic understanding of Ethernet, IP, and software defined networking.
- You have set up the Mininet 2.2.1 virtual machine on your computer
- You have a basic understanding of how Mininet commands work
- You are familiar with the POX Continue reading
Install Gephi on the Mininet VM
This post describes how to install the Gephi graph visualization utility on the Mininet 2.2 virtual machine.
I want to investigate the node and link discovery function of OpenFlow and, to do that, I plan to experiment with some components of the POX SDN controller that interface with the Gephi graph visualization utility. Previously, I set up the Mininet network simulator, which includes the POX SDN controller. The final step is to install Gephi on the Mininet virtual machine.
Unfortunately, I found that the install instructions on the Gephi web site do not work. So, I used another procedure to solve the Java issue I encountered and complete the installation.
The Mininet virtual machine
Log into the Mininet VM via SSH with X forwarding. If needed, review my previous post about setting up the Mininet VM. Ensure both the NAT interface and the host-only network interface are connected.
Java
Gephi runs on Java but Java is not installed in the Mininet VM, which is based on a minimal installation of Ubuntu Server 14.04. So we must install Java.
The Gephi documentation states we need to use the Oracle version of Java, which is not available in the Continue reading