Kolla

The Kolla project is part of the OpenStack TripleO effort, focused on deploying OpenStack environments using Kubernetes and Docker containers.

Getting Started

Kubernetes deployment on bare metal is a complex topic which is beyond the scope of this project at this time. The developers require a development test environment. As a result, one of the developers has created a Heat based deployment tool that can be found here.

Build Docker Images

Images are built by the Kolla project maintainers. It is possible to build unique images with specific changes, but these would end up in a personal namespace. Read the docs directory image workflow documentation for more details.

The Kolla developers build images in the kollaglue namespace for the following services:

• Glance
• Heat
• Keystone
• Mariadb
• Nova
• Rabbitmq
• Neutron
• Mongodb
• Ceilometer
• Zaqar
• Horizon

$ sudo docker search kollaglue

A list of the upstream built docker images will be shown.

Use Kubernetes to Deploy OpenStack

At this point, we believe the key features for a minimum viable feature set are implemented. This includes the capability to launch virtual machines in Nova. One key fact is that networking may not entirely work properly yet until Neutron is finished, so the virtual machines may not actually behave as expected for an end user deployment.

Two options exist for those without an existing Kubernetes environment:

The upstream Kubernetes community provides instructions for running Kubernetes using Vagrant, available from: https://github.com/GoogleCloudPlatform/kubernetes/blob/master/docs/getting-started-guides/vagrant.md

The Kolla developers develop Kolla in OpenStack, using Heat to provision the necessary servers and other resources. If you are familiar with Heat and have a correctly configured environment available, this allows deployment of a working Kubernetes cluster automatically. The Heat templates are available from https://github.com/larsks/heat-kubernetes/. The templates require at least Heat 2014.1.3 (earlier versions have a bug that will prevent the templates from working).

Here are some simple steps to get things rolling using the Heat templates:

1. Clone the repository:

   git clone https://github.com/larsks/heat-kubernetes/
   cd heat-kubernetes
   

2. Create an appropriate image by running the get_image.sh script in this repository. This will generate an image called fedora-20-k8s.qcow2. Upload this image to Glance. You can also obtain an appropriate image from https://fedorapeople.org/groups/heat/kolla/fedora-20-k8s.qcow2

3. Create a file local.yaml with settings appropriate to your OpenStack environment. It should look something like:

   parameters:
     server_image: fedora-20-k8s
     ssh_key_name: sdake
   
   
     dns_nameserver: 8.8.8.8
     external_network_id: 6e7e7701-46a0-49c0-9f06-ac5abc79d6ae
     number_of_minions: 1
     server_flavor: m1.large
   

   You must provide settings for external_network_id and ssh_key_name; these are local to your environment. You will probably also need to provide a value for server_image, which should be the name (or UUID) of a Fedora 20 cloud image or derivative.

4. heat stack-create -f kubecluster.yaml -e local.yaml my-kube-cluster

5. Determine the ip addresses of your cluster hosts by running:

   heat output-show my-kube-cluster kube_minions_external
   

6. Connect to the minion node with ssh fedora@${minion-ip}

7. On the minion node:

   minion$ git clone http://github.com/stackforge/kolla
   minion$ cd kolla
   minion$ ./tools/start
   

Debugging

A few commands for debugging the system.

$ sudo docker images

Lists all images that have been pulled from the upstream kollaglue repository thus far. This can be run on the minion during the ./start operation to check on the download progress.

$ sudo docker ps -a

This will show all processes that docker has started. Removing the -a will show only active processes. This can be run on the minion during the ./start operation to check that the containers are orchestrated.

$ sudo docker logs <containerid>

This shows the logging output of each service in a container. The containerid can be obtained via the docker ps operation. This can be run on the minion during the ./start operation to debug the container.

$ kubectl get pods

This lists all pods of which Kubernetes is aware. This can be run on the master or minion.

$ sudo systemctl restart kube-apiserver
$ sudo systemctl restart kube-scheduler

This command is needed on the master after heat finishes the creation of the Kubernetes system (ie: my-kube-cluster is in CREATE_COMPLETE state). This is just a workaround for a bug in kubernetes that should be fixed soon.

$ journalctl -f -l -xn -u kube-apiserver -u etcd -u kube-scheduler

This shows log output on the server for the various daemons and can be filed in bug reports in the upstream launchpad tracker.

$ journalctl -f -l -xn -u kubelet.service -u kube-proxy -u docker

This shows log output on the minion for the various daemons and can be filed in bug reports in the upstream launchpad tracker.

$ telnet minion_ip 3306

This shows that the Mariadb service is running on the minions. Output should appear as follows

$ telnet 10.0.0.4 3306
Trying 10.0.0.4...
Connected to 10.0.0.4.
Escape character is '^]'.

5.5.39-MariaDB-wsrep

If the connection closes before mysql responds then the proxy is not properly connecting to the database. This can be seen by using jounalctl and watching for a connection error on the node that you can't connect to mysql through.

$ journalctl -f -l -xn -u kube-proxy

If you can conect though one and not the other there's probably a problem with the overlay network. Double check that you're tunning kernel 3.16+ because vxlan support is required. If you kernel version is good try restarting openvswitch on both nodes. This has usually fixed the connection issues.

Directories

• docker - contains artifacts for use with docker build to build appropriate images
• k8s - contains service and pod configuration information for Kubernetes
• tools - contains different tools for interacting with Kolla