GNS3
GNS3 is an open-source, free software platform that allows users to virtualize hardware devices. GNS3 (Graphical Network Simulator) enables the simulation of complex networks using virtual devices. It is widely used by network professionals and students for training and certification preparation.
GNS3 - Install you GNS3 Server¶
From the left navigation menu, select "compute" → "Instances" and click on "Add Instance" Since the GNS3 image is based on Ubuntu, choose Ubuntu under the Operating System filter.
Compute Offering¶
Under the Compute Offering option, select GNS3VM (2.2.54) v2.2. This offering allocates 8 CPUs, 16 GB of memory, and 120 GB of disk space. You can always scale the offering up or down as needed; please refer to the documentation for instructions on how to adjust your instance.
Data Disk¶
Leave the DATA disk unselected by choosing No thanks. This option adds an additional separate disk to your instance. If more space is needed you can always upscale the root disk later; please refer to the documentation for instructions on how to do this.
Networks¶
Choose your network. If no network is available, select Create New Network. Enter the required information as shown in the screenshot.
GNS3 Instance Name¶
After filling in the information, enter a Name for your GNS3 instance. Use your first and last name to identify your server.
Click "Launch Instance"
GNS3 Network¶
GNS3 Configure Firewall for Internet Access¶
After deploying your GNS3 instance, you will need to configure your firewall for internet access. In the left navigation menu, select Network → Guest Networks, then click on your network.
Go to the Egress Rules tab, select ALL under the protocol option, and click Add to create the egress rule. The source CIDR will be selected automatically.
Open Required Ports¶
To open the required ports, go to Public IP Addresses and click on the IP address of your GNS3 appliance.
To allow SSH access, GNS3 web access, GNS3 client access, and VNC client access, the following ports must be allowed in the firewall:
- 22 for SSH
- 80 for the GNS3 web interface and client
- 5000–6000 for connecting the VNC client to the VMs in GNS3
Add the ports to the firewal:
The same ports also need to be forwarded to the GNS3 instance.
- Select the Port Forwarding tab.
- Add the required ports and assign them to the GNS3 instance by clicking the Add button.
GNS3 Client¶
To ensure proper communication and functionality, the GNS3 client version *need to match the server version. The Server version currently in use is version 2.2.54. Follow the link below to download the correct GNS3 vesion.
- From the navigation menu, select Downloads or click Downloads Page
Enable both the Desktop and the Webclient option.
After installing the GNS3 client, configure it to connect to the IP address of your firewall. In the GNS3 client, open Preferences from the Edit menu, or use the shortcut Ctrl + Shift + P.
GNS3 Template Credentials¶
Default Credentials for GNS3 Appliance Templates