Frequently Asked Questions#

I want to..#

Add a new project to SKA organisation#

Develop a Tango device#

Containerise my solution#

A summary of our containerisation standards can be found in the Container Standards CheatSheet.

$ docker -v

  Docker version 1.7.0, build 0baf609

Incorporate my project into the integration environment#

We use Kubernetes as an orchestration layer - refer to our Orchestration Guidelines.

Once a project is ready to form part of the integrated solution, we need to verify that all prerequisites are installed and working properly.

$ kubectl version

  Client Version: version.Info{Major:"1", Minor:"15", GitVersion:"v1.15.1", GitCommit:"4485c6f18cee9a5d3c3b4e523bd27972b1b53892",
  GitTreeState:"clean", BuildDate:"2019-07-18T09:18:22Z", GoVersion:"go1.12.5", Compiler:"gc", Platform:"linux/amd64"}
  The connection to the server localhost:8080 was refused - did you specify the right host or port?

$ minikube

  Minikube is a CLI tool that provisions and manages single-node Kubernetes clusters optimized for development workflows...
  • Launch Kubernetes.

    • Look out for kubectl is now configured to use “minikube” near the end:

 $ sudo -E minikube start --vm-driver=none --extra-config=kubelet.resolv-conf=/var/run/systemd/resolve/resolv.conf

 😄  minikube v0.34.1 on linux (amd64)
 🤹  Configuring local host environment ...

 ⚠️  The 'none' driver provides limited isolation and may reduce system security and reliability.
 ⚠ ️  For more information, see:
 👉  https://gitlab.com/kubernetes/minikube/blob/master/docs/vmdriver-none.md

 ⚠️  kubectl and minikube configuration will be stored in /home/ubuntu
 ⚠️  To use kubectl or minikube commands as your own user, you may
 ⚠️  need to relocate them. For example, to overwrite your own settings:

   ▪ sudo mv /home/ubuntu/.kube /home/ubuntu/.minikube $HOME
   ▪ sudo chown -R $USER /home/ubuntu/.kube /home/ubuntu/.minikube

💡  This can also be done automatically by setting the env var CHANGE_MINIKUBE_NONE_USER=true
🔥  Creating none VM (CPUs=2, Memory=2048MB, Disk=20000MB) ...
📶  "minikube" IP address is 192.168.86.29
🐳  Configuring Docker as the container runtime ...
✨  Preparing Kubernetes environment ...
   ▪ kubelet.resolv-conf=/var/run/systemd/resolve/resolv.conf
🚜  Pulling images required by Kubernetes v1.13.3 ...
🚀  Launching Kubernetes v1.13.3 using kubeadm ...
🔑  Configuring cluster permissions ...
🤔  Verifying component health .....
💗  kubectl is now configured to use "minikube"
🏄  Done! Thank you for using minikube

Test that the connectivity in the cluster works

$ kubectl get pods -n kube-system
NAME                               READY   STATUS    RESTARTS   AGE
coredns-86c58d9df4-5ztg8           1/1     Running   0          3m24s
...

$ helm version
version.BuildInfo{Version:"v3.1.2", GitCommit:"d878d4d45863e42fd5cff6743294a11d28a9abce", GitTreeState:"clean", GoVersion:"go1.13.8"}

...

Note

Until recently, we have been using Helm 2 in all our Ansible Playbooks for provisioning machines and development environments. Helm 2 used Tiller as a deployment service, and would be started in your environment by running the helm init command. This is no longer the case with Helm 3. More info here .

Use this ansible playbook to upgrade your existing Helm 2 to Helm 3.

Once Helm is installed, develop a helm chart for the project. Refer to Helm instructions for guidelines.

Install Helm charts from our own repository#

The SKAMPI repository is in essence a configuration management repository, which basically just consists of a number of Helm charts and instructions for installing them on a kubernetes cluster.

Installing Helm charts from our own Helm Chart Repository is another option, specifically that enables installing different charts during run-time.

To add the SKA Helm chart repo to your local Helm, simply run

$ helm repo add skao https://artefact.skao.int/repository/helm-internal

Working with the Helm chart repository, including how to package and upload charts to our repository, is described here in detail.

Deploy the TMC prototype and Webjive in kubernetes#

The integration gitlab repository can be found at ska-telescope/ska-skampi.

Documentation on deployment can be found at /projects/skampi/en/latest/README.html

Add the helm chart to the skampi repository: Integrating a chart into the SKAMPI repo.

  • Verify k8s integration

    • Launch the integration environment

$  make deploy_all KUBE_NAMESPACE=integration

and verify that the pods are able to startup without any errors

$ watch kubectl get all,pv,pvc,ingress -n integration

Every 2.0s: kubectl get all,pv,pvc -n integration           osboxes: Fri Mar 29 09:25:05 2019

NAME                                          READY   STATUS             RESTARTS   AGE
pod/databaseds-integration-tmc-webui-test-0   1/1     Running            3          117s
pod/rsyslog-integration-tmc-webui-test-0      1/1     Running            0          117s
podtangodb-integration-tmc-webui-test-0      1/1     Running            0          117s
pod/tangotest-integration-tmc-webui-test      1/1     Running            2          117s
pod/tmcprototype-integration-tmc-webui-test   4/5     CrashLoopBackOff   2          117s
pod/webjive-integration-tmc-webui-test-0      4/4     Running            0          117s
...