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Number of NICs is the number of network interface cards you will see inside your VM (e.g.When a VM is selected, you can choose other options for it as well: To avoid confusion and possible errors, it is recomended to use the same identifier name as the name of the VM.
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Choose an identifier name, a VM from the VM list (you may have to refresh the list using the provided button).
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When the connection between GNS3 and VirtualBox have been made, you need to tell GNS3 which VMs it should see and be able to use. Launch the GNS3 startup wizard, select the GNS3 VM, and it should be able to start the VM. # ip addr add IP_address/ subnet_mask dev vboxnet0 See Network configuration#Routing table for more information on assigning IP addresses. Therefore, this must be performed manually in the terminal. For some reason, VirtualBox does not assign the IP to the interface, nor does it enable it. Note the IP address dedicated to the interface in the GUI. In most cases, it will be called vboxnet0 or similar. In File > Host Network Manager, set up a host-only network. To create a network connection between the GNS3 VM and the host OS, a host-only network must be configured. Go to GNS3 Github and download the VirtualBox version of the GNS3 VM with the exact same version number as your GNS3 version. The official GNS3 VM should be used to increase performance. If you do not install the virtualbox-sdk package, you will not get the vboxapi.py script, and GNS3's vboxwrapper.py needs this to connect the VMs. If you already have VirtualBox installed, you should be able to just reinstall it. To avoid any problems with GNS3 not finding VirtualBox, it is recommended to install VirtualBox AFTER you install GNS3. To use VirtualBox machines for your topology, you need to install virtualbox and virtualbox-sdk. GNS3 supports QEMU, VirtualBox and VMware out of the box. When creating your topology (your virtual network), you most likely want to add machines to it. Install them and ensure the libvirtd daemon is running before using GNS3 with Cloud and NAT end devices.
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To make libvirt work correctly, GNS3 needs dnsmasq and ubridge AUR. Libvirt can be used to create the end devices "Cloud" (providing a virtual wan interfaces, isolating the tested network to the other devices in the main network) and NAT.
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Note: Once installed, it is important to enable and start the USER service, where USER is the username for the user-level account on which GNS3 will be run.
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