GNS3

I’ve been using GNS3 to build and test network topologies, and it’s been a game changer for hands-on learning and lab work. Whether I’m practicing routing protocols, experimenting with firewall setups, or replicating real-world network scenarios, GNS3 gives me a sandbox that behaves very similarly to physical gear. The depth of support for different vendors and devices is impressive, and being able to visualize and interact with packet flows adds a level of realism that generic simulators can’t match. It’s especially valuable if you’re prepping for networking certifications or testing network designs before deploying them live. However, it’s not plug-and-play. Getting GNS3 installed with all dependencies (like IOU/IOS images and proper virtualization) can take some dedication — and you’ll need decent hardware to avoid slowdowns once you start connecting many devices. Beginners without networking background may feel overwhelmed at first. Overall, GNS3 is a powerful tool that delivers real value to network engineers and students, but it demands patience and some technical skill — hence a 4-star rating.

There is still some room for improvement but it already is a quality. Fantastic tool for network engineers.

Hi Guys and to ALL those in making GNS3 great, A very nice tool this gns3 is, kudos all round. I have a few feature requests that should be easy to implement: 1 - Please add a 'Close Project' button as well as a menu item under the 'File' menu. REASON: in general closing something like a file or project makes more sense to the everyday user as we were taught this from the 1990's already... 2 - When a topology is made by dragging items to the screen, do not bind the gns3 version (2.1.21 or 2.2 etc. ) to the topology. Instead have a compatible window to state the version number compatibility. REASON: We share topologies between friends/programmers/consultants and not ALL of us prefer to use the latest greatest versions. It will be best to make the topology stand-alone item that can be exported/imported with ease across different versions of GNS3 3 - Please add a feature to the 'Snapshots' window to: --edit the name of the snapshot -- 'Lock' & 'Unlock' the snapshot to prevent ANY changes to it -- 'Autoload' a snapshot upon project opening -- 'Update' a snapshots' items in the window after a config change was done so the user can open the 'Snapshots' window, select the relevant snapshot and click 'Update' . The 'Delete' and 'Restore' features works just great. Thanks Guys, hear from you soon JM

A superb tool for network engineers. Invaluable for study and proof of concept work. And it's free & open source. What more could you ask for?

just brilliant