GNS3 Sourceforge account provides an OVA image ready to run gns3-server for those who want to use Cisco IOS on Unix images . However, at the time of this writing, the gns3-server version is outdated (1.3.3). The client must have the same version as the server to be able to connect to it.

Here is how you can update the gns3-server inside the image. Note that you need Internet access for the update.

  • Download the image from Sourceforge, run it with your favorite hypervisor.
  • Open a console and login, username=root and password=cisco .
  • Type pip search gns3-server to make sure you have Internet access.
  • If it succeeds, then type pip install gns3-server==1.3.10 to install latest version (at the time of this writing, it is 1.3.10).
  • Then type reboot.

Now your client running 1.3.10 should be able to connect to the server successfully.