Installing and Managing Contrail 5.0 Microservices Architecture Using Helm Charts

Understanding Helm Charts

Helm is the package manager for Kubernetes, an open source software for managing containerized systems. The packaging format used by Helm is a chart, a collection of files that describe a related set of Kubernetes resources. Helm charts enable you to define, install, and configure your Kubernetes application. A chart can be used to deploy something simple, like a memcached pod, or something complex, like a full web application stack complete with HTTP servers, databases, and the like.

Starting with Contrail Release 5.0, Contrail Helm charts give you complete life cycle management of installation, update, and delete of Contrail Docker-based containers in a microservices architecture.

The Contrail Helm deployer supports deploying Contrail for OpenStack.

Contrail Helm Deployer Charts

The Contrail Helm deployer uses the following charts.

• helm-toolkit chart

  Contains common templates and functions that are used by every other Contrail Helm chart.

• contrail-thirdparty chart

  Defines and deploys third party containers as Kubernetes resources for Contrail, including:

  • RabbitMQ

  • ZooKeeper

  • Cassandra

  • Kafka

  • Redis

• contrail-controller chart

  Deploys and manages Contrail components as Kubernetes resources, including:

  • control

  • config

  • webui

• contrail-analytics chart

  Deploys and manages Contrail analytics components as Kubernetes resources.

• contrail-vrouter chart

  Deploys and manages Contrail vrouter components as Kubernetes resources.

• contrail-superset chart

  A superset of all other Contrail Helm charts, can be used to install all Kubernetes resources defined in other Contrail charts.

Contrail Kubernetes Resource implementation

All Contrail Helm charts follow a similar approach to implementing Kubernetes resources. For each of the Contrail Release 5.0 containers, configuration input is given as an environment variable in the file values.yaml. Use the variable .Values.contrail_env to define environment variables for the containers.

All of the environment variables are stored in Kubernetes resources called configmaps. The configmaps are loaded into specific containers as environment variables.

Because Contrail is an infrastructure-level application, every pod of Contrail is hosted on the host network namespace. Consequently, the daemonset controller is used to define all Contrail pods, so that each of the Contrail pods are brought up on different nodes to avoid port conflicts.

Example: Contrail Pods Deployment Options

Installing Contrail Using Helm Charts

Use one of the following procedures to install Contrail with OpenStack Ocata using Helm charts:

• Using Helm Charts to Provision Multinode Contrail OpenStack Ocata with High Availability

• Using Helm Charts to Provision All-in-One Contrail with OpenStack Ocata