download cisco router ios image gns3 iou

# masquerade rule that let containers connect # You can see that the Docker server creates a

on the host it adds a NAT rule to iptables:.

on the container it adds a default route to the host ip address of 172.17.42.1.

To allow networking to the outside world docker does two things: This configuration allows each container to talk to the host and to the other containers. Networking GNS3 and containerĪ docker container has a virtual interface, eth0, with an ip assigned to it randomly chosen by docker from the network 172.17.0.0/16, this interface is “piped” to a corresponding interface on the host with a name similar to vethb1ed276 on the host this interface, together with similar interfaces of other docking containers, are bridged together on the docker0 bridge, that has the ip address 172.17.42.1/16. In both cases you need Docker already installed on your Linux system.

Or the image can be pulled from the Docker Registry with: $ sudo docker build -t='digiampietro/gns3-large'. The docker container can be built using the mybuild script or:

set startup.sh as the executable that runs when the container starts.

install Gnome Connection Manager and the gcmconf script.

install QEMU, an emulator similar to VirtualBox.

compile and install iouyap, it is needed to interface the IOU executable with GNS3.

compile and install VPCS, a sort of pc simulator that implements basic network testing functions like dhcp client, ping etc.

install gns3-gui and gns3-server, the two components of GNS3.

compile and install Dynamips (the simulation engine used by GNS3).

install Wireshark for packet capture and analysis from inside GNS3.

install software required by GNS3 and related software.

build the image starting from the latest version of Ubuntu (14.04) officially available on the Docker Registry.

The Docker file is available on the GitHub repository for the gns3-large project and contains instructions to I called the container gns3-large, because it is quite fat, it contains everything needed to build some software included in the image. If you need persistence you have to explicitly declare persistent volumes (folders) on the Dockerfile or you have to explicitly mount a folder, on the host, on a folder, in the docker image, when you start the docker image ( -v option) in our case we explicitly mount the user’s entire home directory inside same directory in the docker image. On the host you see the processe(s) running in a docker container as normal processes.Īnother important feature of docker containers is that when they stop nothing is saved so that when they restart it is as if you are starting a new fresh image. The huge advantage of Docker containers against virtual machines is that they spin-up in milliseconds instead of tens of seconds and, because they share same kernel, don’t have to simulate the entire operating system, so they are much more efficient in terms of host resource usage.

GNS3 is available on Windows, Mac OSX and on Linux, but it shines on Linux because, to use IOU, if you are not on Linux you need a Linux virtual machine running on VirtualBox.īut, because GNS3 glues together many moving parts, it can be troublesome to install everything and to have everything working seamlessly, for this reason i created a Docker image with everything installed, functioning and ready to be used on Linux (or in a Linux virtual machine running in Windows or Mac OSX).ĭocker is another fantastic piece of software that, together with CoreOS and other cloud orchestration projects, like Google’s Kubernetes, is one of the building blocks for the incoming Cloud Revolution.ĭocker containers (or Docker images) have similarities with virtual machines, but they run on same Linux kernel as the host, in a “ chrooted” environment using Cgroups and namespace isolation to provide resource limitation (on cpu and or RAM usage) and isolation from the other host processes that are invisible inside the Docker container.

It also allows to connect the virtual network to the physical network, it is possible to access Internet in the emulated world and vice-versa. GNS3 is a fantastic piece of software, it glues together different open source software and allows to emulate a network that includes Cisco routers (using real Cisco firmware), Cisco switches (using IOU, Cisco IOS on Unix), Cisco ASA and any other devices that can run on Qemu or Virtual Box emulator.

Download cisco router ios image gns3 iou