Tag Archives: Magnum

Openstack Deployment using Containers

Cloud Platforms, Containers & Kubernetes, DevOps & Automation, , , , , ,

I recently saw the Openstack self-healing demo from CoreOS team using Tectonic(Stackanetes project) and I kind of felt that the boundary between Containers and VMs are blurring. In this blog, I discuss the usecase of deploying Openstack using Containers.

We typically think of Openstack as a VM Orchestration tool. Openstack is composed of numerous services and deploying Openstack as one monolithic blob is pretty complex and difficult to maintain. The demo described showed how Containers simplify Openstack deployment. This is a great example of using Microservices architecture to simplify infrastructure deployment.

Following diagram shows the Openstack deployment model using Containers. The diagram below shows how Openstack service containers deploys user VM. The user VMs deployed using Openstack can run Containers as well..

vm_container1.PNG

Following are some notes on the architecture:

  • Openstack services like Nova, Heat, Horizon are containerized using Openstack Kolla project as Docker Containers. Some Openstack services like Nova is composed of multiple Containers.
  • Infrastructure components like Ceph, Openvswitch, Mongodb are also deployed as Containers.
  • For Container deployment, Openstack natively uses Ansible. Kubernetes can also be used for Orchestration.
  • Using Containers for Openstack service containers gives all the build, ship and deploy advantages of Containers.
  • Using orchestration solution like Kubernetes gives all the resiliency and deployment advantages for Openstack services.

This work also shows how Containers and VMs can work closely with each other for lot of use-cases. There are other Openstack projects like Magnum and Kuryr where there is an intersection between Containers and VMs. Magnum project deals with Container orchestration using Openstack and Kuryr project deals with doing Container networking using Openstack Neutron.

References:

Openstack and Docker – Part 2

Cloud Platforms, Containers & Kubernetes, , , ,

This is a continuation of my previous blog on Openstack and Docker. In this blog, I will cover Openstack Docker heat plugin and Magnum.

Following are some of the items that Nova Docker driver cannot do currently:

  1. Passing environment variables
  2. Linking containers
  3. Specifying volumes
  4. Orchestrating and scheduling the containers

Heat docker plugin solves problems 1-3 and partially solves problem 4. Following is the architecture diagram I found in Openstack Docker wiki for heat.

odocker2

  • Nova is not involved here. Openstack heat uses Docker plugin to talk to Docker agent on the host.
  • The host here is the VM spawned. The VM can either be spawned by Nova or Heat can spawn this using Nova driver.
  • Glance is not involved here as the container images are stored in Docker registry.
  • The Heat approach allows us to specify environment variables, link containers, specify volumes as well as orchestrate the host on which the Docker runs.

Using Heat plugin:

Continue reading Openstack and Docker – Part 2 →