TripleO Containers Patching

With the support of only container based deployments, it is important to know that how to edit files used for development to verify end to end deployment with the changes. The puppet manifests changes has to be applied to overcloud-full image, same as existing, in the folder /usr/share/openstack-puppet/modules. And code changes specific to a container has to be applied on the container.

Updating a Package in a Container

Download the RPMs to be update to on the container image, in this post, lets see how to override, openvswitch2.10-ovn-host RPM for the ovn-controller container image.
Create a Dockerfile from the existing ovn-controller image

  FROM 192.168.10.1:8787/rhosp14/openstack-ovn-controller:2019-02-21.1
  ADD openvswitch2.10-ovn-host-2.10.0-54.el7fdn.x86_64.rpm \
    /openvswitch2.10-ovn-host-2.10.0-54.el7fdn.x86_64.rpm
  RUN rpm -Uvh /openvswitch2.10-ovn-host-2.10.0-54.el7fdn.x86_64.rpm
  ENTRYPOINT kolla_start

Build the image with a custom tag “patched” and push it to the container registry

  $ docker build . -t 192.168.10.1:8787/rhosp14/openstack-ovn-controller:patched
  $ docker push 192.168.10.1:8787/rhosp14/openstack-ovn-controller:patched

Updating the image after the deployment in the overcloud node
- Update the image tag to “patched” in the container startup config scripts, for ovn-controller, update the file hashed-docker-container-startup-config-step_4.json with this new tag.
- Apply the modified config file using paunch command

  $ paunch apply --config-id tripleo_step4 \
      --file /var/lib/tripleo-config/hashed-docker-container-startup-config-step_4.json

Using the updated image as part of the deployment
- Create an environment file to override the image for ovn-controller

  parameter_defaults:
    DockerOvnControllerImage: 192.168.10.1:8787/rhosp14/openstack-ovn-controller:patched

Add this environment file to the deploy command

Modify Source Code in Container

Following steps allows to modify a container image in undercloud and upload it to registry so that it could be applied to all the nodes during the deployment.

Run the run command to enter to the container with bash prompt, specify a custom name for this instance

  $ docker run --name server-ovn-patch -it -u root \
      192.168.10.1:8787/rhosp14/openstack-neutron-server-ovn:2019-02-21.1 bash

Modify the required files and exit the container
Commit the run instance to a image with specific tag and push it to the registry

  $ docker commit --change "ENTRYPOINT kolla_start" server-ovn-patch \
      192.168.10.1:8787/rhosp14/openstack-neutron-server-ovn:patched
  $ docker push 192.168.10.1:8787/rhosp14/openstack-neutron-server-ovn:patched

Using the updated image as part of the deployment
- Create an environment file to override the image

  parameter_defaults:
    DockerNeutronApiImage: 192.168.10.1:8787/rhosp14/openstack-neutron-server-ovn:patched

Add this environment file to the deploy command