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Get to Know GENI and SAVI

Hello GENI index Hello GENI index Hello GENI index


1.Use the SAVI Client and the Federation Tool to Create a GENI Slice OMNI Bundle

  • Use SFTP to transfer the Omni Bundle you downloaded in pre-work to the Downloads folder on From the folder in which you have the Omni bundle, run
    $ sftp <savi-username>
    > cd Downloads
    > put omni.bundle
    > bye

Linux or Mac users can use scp

$ scp omni.bundle <savi-username>

Windows users can use winscp

CMD> winscp omni.bundle <savi-username>
  • Using your SAVI credentials, log in to Any ssh tool can be used for this, including Putty and cygwin ssh on Windows, and the builtin terminal tools on any Unix- or Linux-based


$ ssh <savi-username>

  • Once you're logged in, run

$ omni-configure

to configure Omni.

Now download and unpack the GENI-SAVI Federation Tool

$ wget

$ tar xvf tutorial.tar

Generate keys to be used on the SAVI VMs you will be creating

$  cd tutorial
$ ./ generatekey

It will ask you for your SAVI username, password, and project name. Then it will ask you for the key name. Use the name "savi-tutorial".

Pro Tip: Do not use a passphrase!.

Your SAVI keys are now in tutorial/keys, and your GENI keys are in your .ssh folder on Check to make sure that the keys are there.

2. Create a slice on GENI and Add Some VMs to it

We will now create a slice on GENI. Use your GENI username as the slice name. In the tutorial directory,

$ ./ createslice geni <your_geni_username>

Now add VMs at the Cornell and Utah Downtown Data Center racks

$ ./ createvm geni slice-name Ubuntu-14-04
$ ./ createvm geni slice-name Ubuntu-14-04

This will take about a minute. It will then come back with a response of the form

  Result Summary: Got Reserved resources RSpec from utahddc-geniracks-net. Reservation at utahddc-ig in slice rizpan expires at 2015-05-25 22:59:40 (UTC).

 To connect to the created VM please use to the given hostname="<name>"

The machine will now be in a booting state. It will take about 5-10 minutes before you can log in. We'll use the time productively and create some SAVI VMs while we wait.

3. Create VMs on SAVI at Toronto and Victoria

The general form of the command to create a VM on SAVI is

$ ./ createvm savi <tenant_name> <location> <os_image_name> <machine_name> <access_key>l <vm-name>

we have chosen values for all parameters. The vm-name should be your geni-username, followed by the sitename. E.g., for rickmcg, the name at Toronto will be rickmcg-toronto

$ ./ createvm savi <tenant_name> toronto ubuntu-14-04-64 small savi_tutorial <geni_username>-toronto
$  ./ createvm savi <tenant_name> victoria ubuntu-14-04-64 small savi_tutorial <geni-username>-victoria

We now have VMs at Cornell, Utah, Toronto, and Victoria. Check the status of your resources on both GENI and SAVI

$ ./ listinstance geni
$ ./ listinstance savi

Notice that access to the SAVI machines are by IP address

4. Learn some basic concepts of Ansible

Ansible ( is a free, open-source, intuitive IT automation tool that is well-suited to the tasks in this tutorial. Ansible commands can be run from the command line or put in a YAML file called a playbook. We will be creating an Ansible playbook to run the parameterized HTTP query described earlier.

Two basic concepts in Ansible are inventories and modules. An inventory is a list of hosts to be managed by Ansible, organized into groups. When you run Ansible commands, either from the command-line or in a playbook, you specify the host group that the command should operate on. In this way Ansible commands can operate on many hosts in parallel. Take a look at the Ansible inventory in your ansible-hosts file. This is basically the equivalent of the ssh-config except it's specialized for Ansible.

A task in Ansible consists of a module and some arguments for the module. A module provides a declarative abstraction on top of standard shell commands. So for example, in the shell on an Ubuntu machine you might install package “foo” like this:

$ sudo apt-get update
$ sudo apt-get install foo

An equivalent Ansible task in a playbook would look like:

- apt: name=foo state=latest update_cache=yes 

Or the same Ansible task could be invoked directly on the command line like this:

$ ansible remote-machine -m apt -a "name=foo state=latest update_cache=yes"

The task uses the apt module, and tells Ansible: “Make sure the latest version of package foo is installed”. There are many other modules which are well-documented at

Here are a few Ansible tasks to run, to get some experience with the command-line interface.

(a) Create an Ansible Hosts file

An Ansible hosts file is of the form

or ansible_ssh_host= ansible_ssh_host=

Create an Ansible Hosts file for your slice. An example is here:

(b) The ping module

The ping module simply tries to do a SSH login to a node and reports success or failure. Run the following command on your controller:

$ ansible nodes -i ansible-hosts -m ping

If you don’t see success everywhere then there is something wrong with your setup. Ask one of the tutorial leaders for help.

(c) The shell module

The shell module lets you run arbitrary SSH commands in parallel across a set of hosts. It’s useful for poking around, or if there is no Ansible module with the functionality you need. Try it out:

$ ansible nodes -i ansible-hosts -m shell -a "hostname"

You can replace hostname above with any other Linux command.

(d) The setup module

The setup module gathers a bunch of information about each node and saves it in variables that you can reference in your Ansible playbooks. This will be really useful to do the tutorial! Try it out on a node to see what it collects (replace <your-vm> with your hostname):

$ ansible <yourvm> -i ansible-hosts -m setup

(e) A simple playbook

Next, we will look at a simple Ansible playbook. An Ansible playbook is a YAML file containing a list of Ansible tasks. Copy the playbook below into a file called test.yaml:

- hosts: nodes
  remote_user: root
  - name: An example of a debug statement
    debug: var=ansible_hostname

Run the playbook as:

$ ansible-playbook -i ansible-hosts test.yaml

The setup module is run automatically at the beginning of a playbook to populate variables for each node. The above playbook will dump the value of each node’s ansible_hostname variable. To run the playbook on a single node, replace nodes with the name of one of your slice nodes (e.g.,

5. Create and run an Ansible playbook to install the software you'll need

Now you should have enough knowledge about Ansible to write a playbook to install the software you'll need on all the nodes. Below is a skeleton Ansible playbook that you can use. You will need to fill in the bits marked # INSERT ARGUMENTS HERE to perform the actions described in the name lines. If you get stuck at any point, you can take a look at this solution.

- hosts: nodes
  remote_user: root
  - name: Update apt cache

  - name: Install dnsutils (for dig)

  - name: Install geoip-bin (for geoiplookup)

Run this playbook on your Ansible control machine against all the nodes in your slice.

Pro Tip: use the -f argument to ansible-playbook to speed things up -- it lets you control the number of nodes to operate on in parallel, and the default is 5. Specifying -f 20 will run the playbook's tasks against all your slicelet nodes in parallel.

Next: Run Experiment

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