GNS3 2.0 Architecture and schema Part 1: What is the GNS3 Controller?

Key Takeaways

[Music] in this video I'm going to discuss the gns3 architecture specifically with regards to version two of gns3 now when you first start with gns3 it can sometimes be overwhelming as there are many terms and Concepts used such as gns3 GUI the gns3 VM vpcs qmu iosv iOS V layer 2 bolt-in hubs bolt-in switches VMware and virtual box integration and so forth and so on now Greg asked this question on the community is there a document somewhere that explains gns 3 its parts and how they fit together something as simple as an architecture diagram so firstly Greg asked the question in the right place technical questions should be asked in the community because there's a large community that can help you as well as the core developers Julian and Jeremy answering questions through the community Julian has pointed out this document where you can get the latest API documentation and that's to do with 1.5.4 development version as well as a documentation talking about version 2.0 and this documentation as well as 2.1 is the documentation that I'm going to talk about because in this document we have a schema of gns3 as well as the different components that make up gns 3 so firstly gns3 is split into four parts or four components we have the GS3 guei that's probably what most of us are familiar with we have this gooey interface that we can build topologies on and interact with devices through now in the past we used to only have the guy and a lot of the logic and control was contained in the GUI that changes in version 2.0 so as Julian says here the difference between 1.x and 2.x is that in 1.x the client is smart and has knowledge of the topology where where as in version 2.0 all the logic is in the controller and uses a RAC API this was changed for multiple reasons but one of them is to simplify the life of third parties genus 3 has a rest API and you can use applications such as curl to interact directly with the API and automate your topologies in gns 3 so if you are writing a third party application you can make use of this API to build topologies programmatically personally I think this is a great idea because with the way that the world is moving with regards to network Automation and network programmability it makes sense that gus3 also exposes apis that developers or that Network Engineers can use to interact with the application so first component is the guei so we have the GS3 GUI that talks to a controller this is the GS3 server so we have that as a process running within the gns3 VM we also have the compute servers running on the gns 3 VM they manage various components such as qmu IOU and dynamips which are the various emulators used by gns 3 so the controller is the brains there's only one controller that doesn't run in the guy that runs within the genus 3 VM in genus 3 2.0 the brains are moved to the controller so the guey displays the topology the guy only has direct contact with the controller the compute is where emulators are executed if the compute is on the same server as the controller they would run in the same process when you add a node to your topology such as an iOS V router an instance of the emulator is started so here I've got two iOS V routers so instances of qmu are started to allow me to run multiple routers now this might sound very complex but from a user's point of view it's very very simple I have a GUI and I integrate the guy with the gns3 VM see my other videos where I show you how to integrate the GUI with the junus 3 VM but under the hood there's a lot of options and complexity that's hidden from us as the user so in the same way that you drive a car where you drive the car but don't understand how the internal combustion engine necessarily works genus 3 has abstracted you from the details of the application so we as users are abstracted or have the complexity hidden from us which is great we use iPhones or Android phones but don't necessarily understand GSM or all the chips and components that make up a phone in the same way we would use the js3 GUI to interact with the controller but all of this internal complexity is hidden from us now in later releases we may have a gns3 web interface that's not available in version 1.5 or 2.0 which are the current releases at the time of this recording this recording is been done in January 2017 so if you're watching this video in the future check on the GS3 website if a newer release of GS3 is available that includes the GS3 web interface I want to thank you for watching if you've enjoyed this video please like it and please subscribe to my YouTube channel I wish you all the very best [Music]