gns3

The content in this post is intended for educational and informational purposes only. All software rights belong to their respective owners. I’ve read quite a few tutorials on Netmiko with GNS3, but none of them show you how to directly utilize the console connection as the management interface for Cisco devices. In addition to the CiscoIosSSH driver, Kirk Byers also implemented the CiscoIosTelnet driver for establishing a connection to a Cisco device. This is perfect for GNS3 because the default console connection is essentially a Telnet connection without authentication. ...

The content in this post is intended for educational and informational purposes only. All software rights belong to their respective owners. Cisco includes the IOS on Linux (IOL) images available with the Cisco Modeling Labs (CML) Free Tier . Because IOL runs modern Cisco IOS-XE as a native Linux binary, it offers a lightweight, resource-friendly alternative for network emulation. This post will guide you through the process of adding Cisco IOL devices using GNS3 on macOS. ...

Most GNS3 users are familiar with VPCS . It’s the go-to device for simulating a simple endpoint node in our network labs. VPCS is suitable for the basics, but Docker supplies a selection of more feature-rich endpoint types. This post provides an example using Alpine Linux . Prerequisites GNS3 with macOS on Apple Silicon GNS3 client Steps Open your favorite terminal emulator. Download the latest alpine Docker image from Docker Hub . ...

As of the date of this post, GNS3 does not provide a native client for macOS on Apple Silicon. This post aims to address that issue. While this post serves as a companion to GNS3 with macOS on Apple Silicon , the GNS3 client described here will also function with other types of remote GNS3 servers. Prerequisites Mac computer with Apple silicon macOS Sequoia Git Steps Open your favorite terminal emulator. We will be working from the command line for the majority of the following steps. ...

The content in this post is intended for educational and informational purposes only. All software rights belong to their respective owners. Dynamips may seem to be a bygone technology for the present day, but it’s still a great solution for learning routing concepts on emulated Cisco router platforms. Want to kick it old school with the Cisco 7200 Series Router? ...

Ghostty is my primary terminal emulator for macOS, but I prefer to use a separate terminal emulator for GNS3 console (telnet) connections. After some research, I decided on Alacritty . It’s lightweight and supports the command-line options we need for GNS3. There are several ways to install Alacritty and Telnet, but I use MacPorts in this post. Steps Open your favorite terminal emulator (besides Alacritty 😉). Update the local ports tree with the global MacPorts ports repository. ...

Hosting a local GNS3 server inside an OrbStack Linux machine on Apple Silicon offers a flexible networking lab environment, though it introduces a few key constraints: No x86_64 KVM virtualization: Hardware acceleration is unavailable for nested x86_64 VMs. Emulation overhead: Running x86_64 Linux binaries relies on Rosetta emulation, introducing a slight performance penalty. Network limitation: OrbStack uses a custom-built virtual network stack that does not support bridged networking . The Cloud and NAT nodes will not function. Note: QEMU and libvirt are disabled due to these constraints. ...

After opening the GNS3 client and starting nodes, we primarily access the remote virtual devices with a console connection. This console connection is either Telnet, VNC, or SPICE. A console connection covers our requirement for physical access to virtual devices, but today, most administrative tasks are carried out with a link to the network management interface . I define the GNS3 server as remote if the gns3server process is not running on the host operating system. I consider the GNS3 VM remote because the gns3server process runs on a guest operating system (Ubuntu). ...

This post is a companion to the previous GNS3 with Microsoft Azure post. For many of us, an asymmetrical Internet connection usually equates to a much slower upload than download speed. Specifically, in our case, this results in a time-consuming process of uploading GNS3 image files to our remote gns3server VM instance. What if we need to recreate the disk attached to our gns3server VM instance? Modify the type (i.e., HDD to SSD) or decrease the size of the disk, which again would require us to recreate the disk? What if we need to spin up multiple gns3server VM instances for training purposes? Each situation may require a good amount of unnecessary (re)uploading. ...

Microsoft Azure is one of the big three public cloud computing providers for services such as virtual machines (VMs), containers, server-less computing, and machine learning. Azure is a large platform, but we’re focused solely on the Infrastructure as a Service (IaaS) resources in this guide. The GNS3 architecture is comprised of three primary components: User Interface (UI), Controller, and the (Compute) Server. The Server is the component that puts a strain on computer hardware resources. The more routers, switches, firewalls, and servers we add to our GNS3 topologies, the more CPU, RAM, and data storage we require. We usually come to a point where the hardware requirements of our GNS3 labs may exceed what our laptops and desktops can deliver. ...