In this article I will show you how to create new projects with GNS3 application. If you haven’t installed the GNS3 application, you can check out an older article here.Opening the application, you will see the following pop up window. Here you can type in the name you want your new GNS3 project to have. I named mine “ProjectTest”. Also, you can define the project files path. The small button next to the text field will help you to navigate your hdd and find the folder you want to use as the project files repository. Press the OK button to save the settings.
This is the empty workspace of GNS3. The first thing you have to do before start adding network devices is to show to the software where to find real IOS images to use for simulation.
In order to do that go at Edit>IOS images and hypervisors. Push the file browser button next of the Image file field.
Show to the mini file browser the path to an uncompressed IOS Image file. Press Open button.
GNS3 will check the file and will recognize the platform and the model for which the image is made for. Verify the information and push the Save button to save the setting.
After saving, the path to the IOS image will be added. Following the procedure you can add more IOS Images to fit your need for emulating. You can push Close button to close the window.
Now, you are ready to start drawing your network. You can drag and drop the devices from the left panel to the white area in the middle of the screen. When you initialy add a device in your workspace, the device is un-configured, with minimum hardware installed.
In order to edit the hardware part of the, right click on it and press “Configure”.
This window will appear. Chose “R1” to configure the first router.
At the right side of the window there are four tabs. In the first tab named “General” displayed information about the router hardware, like the platform, model, the assigned IOS Image. Notice that there is no start up configuration for the router.
Selecting the second tab in the right side, you can configure the amount of the several type of memories for your router. Please, be adviced about the memory needs for each IOS image version from CISCO.
Going on, on the third tab we can add slots with interfaces to our router. There are several option for adapters and wics. Don’t hesitate to play around with the options.
At the last tab named “Advanced”, you can configure some options like the configuration register, base mac, etc. Please, do not change any value of this fields unless you know what are you doing. Follow thw same prosedures to configure more than one router by changing the sellected router from the panel at the left side. Don’t forget to press “Apply” and/or “OK” to apply/save the settings for your router.
Now, we have our routers standing alone. We must connect them. To do so, we press the rj45 button and select the “Manual” option.
Clicking on a router, you will see all the available interfaces. Select one and click the router you want to be connected.
Clicking the other router, you will see the available interfaces. Select the one you want to be connected.
You have your routers connected. Pointing on a router or the connection you can see several information about them.
Now, it’s time to power up the routers. To do that just press the green play button.
Using the windows task manager you will see the cpu working at maximum.
In order to avoid destroying your cpu, right clicj on a router and select “Idle PC”. This will test your pc and evaluate several factors on your hardware and software.
A pop up window will appear asking you to select an option, making some recommendations. It’s better to select one of them. The recommendations are marked with an asterisk “*”.
After that, you will see on the tasking manager the cpu usage will be on proper level.
That’s it. No, you can start using your routers, make tests on configurations, etc. You can open the routers consoles pressing the console button.
You can create several network configurations and work with them like using real equipment. Just follow the same steps as I did.
Enjoy GNS3 software until the next tutorial!