iot-usecase-k8

Deploy InfluxDB and Grafana on my kubernetes cluster

Tasks

• Pass the namespace as Gitlab environment variable
  Can I mention the environment variable inside the manifest/grafana-pv.yml file and issue the script kubectl apply -f manifest/grafana-pv.yml?
  No: Because these are gitlab environment variable and kubectl command usually do not update the yml files before applyting the resource. kubectl expect that file contains all the necessary information and do not require any preprocessing where the variables will be replace by the actuall value
• Can I access the container in -it (interactive mode) present in the pod?
  It is assumed that that pod contain single containery.
  In this case, the syntax is kubectl exec -it [pod name] -- [command]. For example kubectl exec -it influxdb-78c5898b88-2l5zt -- sh will let you invoke the sh terminal in the container present in influxdb-78c5898b88-2l5zt pod.
• What a Gitlab-agent for kubernets can do?
  Please follow this section https://about.gitlab.com/blog/2021/09/10/setting-up-the-k-agent/#roles-and-bindings
• How to assign a worker role to a node?
  Go to the the terminal of any node and enter the kubectl label command: kubectl label node [nodename] node-role.kubernetes.io/worker=worker
  for example: kubectl label node node2 node-role.kubernetes.io/worker=worker
• if you delete the a node with kubectl delete node node2 command, how can you get that back?
  Simply apply the following resource using kubectl apply command\

{
  "kind": "Node",
  "apiVersion": "v1",
  "metadata": {
    "name": "node2",
    "labels": {
      "name": "node2",
      "node-role.kubernetes.io/master":"master",
      "kubernetes.io/hostname":"node2",
      "node-role.kubernetes.io/control-plane":"control-plane"
    }
  }
}

• If I have two nodes and both are having control-plane and master, how can update the role of one node to worker and delte the old role?

Next Tasks

• Create a folder, for the persistent volume for the grafana-pv.yml and influxdb-pv.yml. So instead of creating the directory for the volume manually, I want to check and create the directory automatically.
• Can we have two agents?

kubernetes + GitlabCICD

[x] Install Gitlab agent on kubernetes cluster

src: https://docs.gitlab.com/ee/user/clusters/agent/install/ STATUS: Completed

[] Install Kubernetes Dashboard from Gitlab Repo

STATUS: Completed

[] Install Grafana Dashboard from Gitlab Repo

STATUS: Completed

[] Install influxDB from Gitlab Repo

STATUS: Completed

[] Install GraphDB from Gitlab Repo

Manually, I have attached a new volume of 40GB HDD to node3.
STATUS: WIP
Creation of the related resources (including PV, PVC, deployments, etc) are created from the CLI
SRC: https://hub.docker.com/r/ontotext/graphdb/