GNS3 – network simulator

Graphical Network Simulator-3 (GNS3) is software that allows users to emulate, configure, test, and troubleshoot virtual and real networks.

It consists of a GNS3-all-in-one software (GUI) and the GNS3 virtual machine (VM).

GNS3 can help you prepare for certification exams such as the Cisco CCNA, but also help you test and verify real world deployments.

Key Features

• Combining virtual and real devices:
  • GNS3 mimics or emulates the hardware of a device and you run actual images on the virtual device. For example, you could copy the Cisco IOS from a real, physical Cisco router and run that on a virtual, emulated Cisco router in GNS3.
  • GNS3 simulates the features and functionality of a device such as a switch. You are not running actual operating systems (such as Cisco IOS), but rather, a simulated device developed by GNS3, like the built-in layer 2 switch.
• Using Dynamips emulation software to simulate Cisco IOS.
• Creating a customized network topology.
• Verifying configurations.
• No limitation on number of devices supported (the only limitation is your hardware: CPU and memory).
• Supports multiple switching options (NM-ESW16 Etherswitch module, IOU/IOL Layer 2 images, VIRL IOSvL2).
• Supports all VIRL images (IOSv, IOSvL2, IOS-XRv, CSR1000v, NX-OSv, ASAv).
• Supports multi vendor environments.
• Can be run with or without hypervisors.
• Native support for Linux without the need for need for additional virtualization software.
• Capturing packets with the built-in SolarWinds response time viewer for Wireshark tool.

Website: github.com/GNS3/gns3-gui
Support:
Developer: GNS3
License: GNU General Public License v3.0

GNS3 is written in Python. Learn Python with our recommended free books and free tutorials.

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