Version 25 (modified by Vic Thomas, 6 years ago) (diff)


Understanding the AM API using Content Centric Networking

Image Map

1. Design the Experiment

  1. In today's experiment you will use resources at the aggregate listed on the worksheet. If you don't have a worksheet use Clemson InstaGENI (aka

2. Establish the Environment

2.1 Pre-work: Ensure SSH keys are setup

Verify that you have at least one public key associated with your account. To do that, after you login to the portal check under your Profile, under the SSH keys tab. If you do not have SSH keys associated yet, please follow the instructions on that tab of the Portal.

2.2 Configure Omni

  1. Login to the GENI Portal
  2. Click on the `Profile tab` link on the top of your screen. Then click on the `Configure omni` tab under `PROFILE`.

Figure 2-1 Click on the Configure omni tab under Profile.
  1. Click on the `Download your omni data` button under step 2.

Figure 2-2 Download your omni data under step 2.
  1. If this is the first time you try to access your GENI certificate you will have to generate one. Click on the `generate a certificate` link.

Figure 2-3 Click on Generate a certificate.
  1. Unless you really understand how SSL certificates work, choose the simple option. Click on the `Generate Combined Certificate and Key File` button and then click on `Close`. You will be taken back to the download page with the warning. Reload the page to enable the download button.

Figure 2-4 Click on Generate Combined Certificate and Key File.
  1. If you are a member of more than one project, select which project you would like to be the default one for running experiments in GENI. You can always change the project that is used by the `-r` command line option of Omni. Then click on `Download your omni data`.

Figure 2-5 Click on Download your omni data.
  1. The bundle will be saved at ~/Downloads/omni.bundle
  2. Open a terminal window and type:
    The cert and key files you need will be installed in the appropriate folders.

3. Obtain Resources

3.1 Create a slice

Create a slice using omni and the slice name of your choice. From now on that slice name will be referred to as SLICENAME.

$ omni createslice SLICENAME

3.2. Load a simple topology in jFed

For this exercise, we will edit an existing RSpec file. Start by loading this predefined topology into jFed.

  1. In the Portal, launch jFed for this slice.
  2. From the jFed Experimenter Toolkit menu (see figure), select the Open URL button.
Import an RSpec into jFed
Figure 3-1 Import an RSpec into jFed.
  1. Enter the URL for the RSpec:
    then click Ok.
  2. When jFed pops up a message asking you to pick a manager to use, select the manager listed on your worksheet from the list. After you pick an aggregate manager, a network topology should appear on the canvas.
    Pick Aggregate Manager
    Figure 3-2 Pick an Aggregate Manager.
    Because this RSpec file contains a generic description of resources and does not specify any particular aggregate manager, jFed will pop up a message asking you to specify an aggregate to use:
    Assign these nodes now ....

3.3. Modify the RSpec to automatically install and execute CCNX software

For this experiment, we need to install the following software on the nodes:

  • The CCNX software (ccnx-0.6.1-F15-x64.tar.gz)
  • Scripts that set up the CCNX software (ccnx-setup.tar.gz)
  • Scripts used to pull atmospheric precipitation data using the CCNX protocol (ccnx-atmos-F15-x64.tar.gz)

When the nodes start up, we need the following scripts to be executed:

  • Script that sets up the node (node-setup)
  • Script that sets up the ccnx protocol (ccnx-setup)
  • Script that setup up ccnx protocol routes (add-precip-routes)

We automate the installation and running of the software using install and execute scripts in the RSpec.

  1. Click on the collab node (see figure) to manipulate details of the node configuration.
    Note When you open the node information, you should see options like those in the figure.

Figure 3-3 Edit the nodes
  1. The way we will request installation of the proper software and execution of our experiment is to add install and execute services.

Figure 3-4 Specify the install and execute scripts
  1. First, select "Boot Scripts" tab as shown and then the green "+" button after Download sources:. In the URL box enter (cut-and-paste):
    and enter
    in the box next to it (labeled 'Install Path').

    Now, select the green "+" after Download sources: again. This time add:
    and enter
    in the box next to it (labeled 'Install Path').

    Similarly, add a third install service:
    and enter
    in the box next to it (labeled 'Install Path'). Note the different install directory this time.

  2. In a similar manner, use the green "+" button after Execute commands: to add three execute services on this node:
    cd /tmp/ccnx-setup &&  ./node-setup
    cd /tmp/ccnx-setup &&  ./add-precip-routes rsrchr
    cd /tmp/ccnx-setup && ./ccnx-setup router 4
  3. Be very careful when entering this information -- these commands will not be executed yet, so it will be some time before you will see any relevant error messages if there is a mistake here.
  1. Once both the install and execute services are specified, click anywhere in the main pane to have the options window disappear.
  2. You DO NOT have to specify install and execute scripts for the other nodes as they have already been done for you. You can check this by clicking on these nodes.

3.4. Export the modified request RSpec

Now we will pull back some of the covers and inspect exactly what jFed has been doing for us when preparing the RSpecs for the experiments we design. Each node and link has a corresponding element in the RSpec, and the details of the component configuration (such as the install and execute services we requested above) are specified with attributes, or sometimes child elements, within those portions of the document.

  1. From the jFed Experimenter Toolkit window (see figure), select the RSpec Editor tab. This will bring up a window showing the current RSpec -- please take a moment to inspect it. The `<node>` and `<link>` elements contain the specification for the components we will request, and if you look closely, you will be able to see the install and execute service elements you added earlier.

Figure 3-5 View the final request RSpec
  1. Use the Save to file button (in the upper left) to a local copy of your RSpec with the name ccn_precip_gec21.xml.rspec. We'll use this in the next step to demonstrate how other client tools also use RSpec files to communicate requests to aggregate managers.

Figure 3-6 Save the final request RSpec

3.6. Instantiate the new experiment using Omni

For this step, we'll change the approach a bit and switch to a new client tool, the command line Omni client.

From a terminal, please enter the command:


where AM_NICKNAME is the nickname for your assigned aggregate manager and SLICENAME is the name of the slice you created earlier (both of these are given on your worksheet). RSPEC_FILE should be replaced with the filename of the RSpec you saved in step 4.

If all is well, Omni should give you a number of informational messages, such as:

INFO:omni:Loading config file /home/geni/.gcf/omni_config

It should quickly proceed to the point where it makes the request to the remote manager:

INFO:omni:Creating sliver(s) from rspec file /home/geni/Downloads/experiments.rspec for slice ...

This step can sometimes be time-consuming, so please be patient. If it succeeds, within a couple of minutes Omni should report:

INFO:omni: Completed createsliver:

and your resource reservation is complete!


Next: Execute