Hands-On Tutorial: Developing and Onboarding Services in CORD

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Stephanie Patterson
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1 Hands-On Tutorial: Developing and Onboarding Services in CORD CORD BUILD 2017 Customize templateservice Add the service description and VM image to a profile Onboard the service Verify that the service has been onboarded Change the service configuration Modify the service synchronizer Slides t#slide=id.g274e395206_0_8 Customize templateservice To create a new service in CORD 4.0, normally you would create an. xproto file, run the xosgenx tool to generate a synchronizer stub from this file, write a service onboarding recipe, and then add the new service to the build system. In the interest of simplicity we re going to modify an existing templateservice in place and onboard our modified service into the running POD. Customize the service model The model is where we store information required to manage the VNF in CORD -- either global configuration for the VNF service (the Service object) or VM-specific configuration (the ServiceInstance object). Here we will simply add a string to each model that we can set via the GUI or a TOSCA recipe. $ cd ~/cord/orchestration/xos_services/templateservice/xos Edit service.xproto. Add a message field to each model. It should look like the following: message TemplateService (Service){ option verbose_name = "Template Service";

2 required string message = 1 [help_text = "A Message to Display", max_length = 254, null = False, db_index = False, blank = False]; } message TemplateServiceInstance (TenantWithContainer){ option verbose_name = "Template Service Instance"; required string message = 1 [help_text = "A Message to Display", max_length = 254, null = False, db_index = False, blank = False]; } Customize the service synchronizer The service synchronizer is responsible for configuring the service VM after it has been brought up in OpenStack. For some VNFs, the configuration method is to SSH into the VM, write some configuration files, and run the software. Our VNF image comes pre-loaded with Apache; we will write an index.html file with information from the model and start Apache. This section simply walks through the steps involved to build out this simple synchronizer. For more details about implementing synchronizers, please consult the Writing Synchronizers section of the CORD Guide. $ cd synchronizer/steps Edit sync_serviceinstance.py. Add new fields from the model to the get_extra_attributes() function so that they are available to the Ansible playbook. def get_extra_attributes(self, o): fields = {} fields['service_instance_message'] = o.message service = self.get_service(o) fields['service_message'] = service.message return fields Edit serviceinstance_playbook.yaml. The playbook is written using Ansible ( ). Edit it to look like this: - hosts: "{{ instance_name }}" connection: ssh user: ubuntu sudo: yes gather_facts: no vars: - service_instance_message: "{{ service_instance_message }}" - service_message: "{{ service_message }}"

3 tasks: - name: Write index.html file to apache document root template: src=../templates/index.html.j2 dest=/var/www/html/index.html - name: Start apache service: name=apache2 state=started Go to the templates directory $ cd.. $ mkdir templates $ cd templates (full path: ~/cord/orchestration/xos_services/templateservice/xos/synchronizers/t emplates ) Create index.html.j2 and edit it to contain the following text, which uses the variables set in the playbook: MyVNFService Service Message: "{{ service_message }}" Service Instance Message: "{{ service_instance_message }}" Add the service description and VM image to a profile A profile describes the list of services and other resources to be loaded onto the CORD POD. We will start with a base profile that has a set of generic CORD services. $ cd ~/cord/build/platform-install/profile_manifests Edit base-cord.yml. Uncomment the following, under xos_services: # An example of adding a new service to the profile - name: templateservice path: orchestration/xos_services/templateservice

4 keypair: templateservice_rsa Your new service will spin up VMs based on your VNF image. At the bottom of base-cord.yml, replace xos_images with the following: xos_images: - name: "my-vnf-image" url: " checksum: "sha256:2c d09f55ef e038e8da4e9dd7ec92024b1fe4d69772b815 a78" A TOSCA recipe can be used to bring up the new service in XOS. The recipe can also create a service instance, which will spin up a VM for the service and configure it via the synchronizer. In base-cord.yml, uncomment these lines: # An example of adding TOSCA for a service using the new engine. xos_new_tosca_config_templates: - template-service.yaml The last step is to change the TOSCA recipe to specify that the VM should use the new image. $ cd../roles/cord-profile/templates/ Edit template-service.yaml.j2. Change all occurrences of trusty-server-multi-nic to my-vnf-image in this file. NOTE: In this tutorial you are modifying an existing service. If instead you were adding a new service from scratch, a few more steps would be necessary to integrate the service with the build system: (DO NOT PERFORM THESE STEPS FOR THE TUTORIAL) Add the service to ~/cord/build/docker_images.yml Add the service synchronizer image to docker_image_whitelist in these files: ~/cord/build/scenarios/cord/config.yml ~/cord/build/scenarios/single/config.yml Add the service to the manifest file: ~/cord/.repo/manifest.xml Run git init in the service s source tree, if it is not already checked into a Git repo. The CORD team is working on streamlining the process. Onboard the service Now that the service code is ready and the service s information has been added to the profile and TOSCA recipe, we will add the new service (models and synchronizer) to the running POD. To do this, execute the following set of commands:

5 $ cd ~/cord/build $ make xos-teardown $ make clean-profile $ make build $ make compute-node-refresh Running through these steps should take about minutes in total. Verify that the service has been onboarded Log into the XOS GUI. You should see the new service on the left-hand side. Verify that the VNF VM has been created as follows: $ ssh head1 $ source /opt/cord_profile/admin-openrc.sh $ nova list --all-tenants Verify that the VNF VM has been configured correctly. The public IP of VM is displayed in the output of the command above: $ curl --interface fabric IP of VM> The curl command should show you the page written by the synchronizer (i.e., the VNF configuration). Change the service configuration Changing the service s configuration in XOS can dynamically update the VNF configuration. The synchronizer will re-write the configuration based on updates to the model. To see this in action: Change the TemplateService s Message field in the XOS GUI and click Save Change the TemplateServiceInstance s Message field in the XOS GUI and click Save Wait a few seconds, and re-run the curl command above. You should see the new messages in the output.

6 Modify the service synchronizer If the VNF configuration file format needs to change, we can modify the synchronizer and deploy a new version onto the POD. To see this in action: $ cd ~/cord/orchestration/xos_services/templateservice $ cd xos/synchronizer/templates/ Edit index.html.j2, add the following line at the bottom: We have modified the VNF configuration file template! To deploy a service synchronizer using the new configuration template onto the POD: $ cd ~/cord/build $ make xos-update-images $ make build After these steps have completed, go into the XOS GUI and click Save. This step is necessary to trigger the service synchronizer to update the configuration. Wait a few seconds, then run the curl command to see the updated page. CONGRATULATIONS! YOU HAVE COMPLETED THE HANDS-ON TUTORIAL.

XOS Data Modeling Abstractions. XOS APIs. Models. Policies. References. VNF mechanisms DJANGO. Docker Containers. Docker Containers.

XOS Data Modeling Abstractions XOS APIs Models GRPC TOSCA References Policies DJANGO Docker Containers Docker Containers OpenStack VM VNF mechanisms XOS Data Modeling Abstractions (Technology-agnostic)