Deployment on kubernetes cluster

Introduction

The documentation is about how to deploy delfin on a single node kind kubernetes cluster where all the services of delfin are deployed as individual deployments inside a kubernetes cluster

The steps to deploy delfin on a kubernetes cluster

Pre-requisites

  • This installation is tested on Ubuntu 18.04.
  • root user is REQUIRED before the installation work starts.

This is test on a single node kind kubernetes cluster.
Root user is required for the installation.

Note: The deployment will be further tested on kubeadm kubernetes setup(in future)

The required packages:

apt-get install -y libltdl7 libseccomp2 git curl wget make

Install docker

wget https://download.docker.com/linux/ubuntu/dists/xenial/pool/stable/amd64/docker-ce_18.03.1~ce-0~ubuntu_amd64.deb
dpkg -i docker-ce_18.03.1~ce-0~ubuntu_amd64.deb

Install Kind

curl -Lo ./kind https://github.com/kubernetes-sigs/kind/releases/download/v0.11.1/kind-linux-amd64
chmod +x ./kind
mv ./kind /<some-dir-in-your-PATH>/kind
# here some-dir-in-PATH to be replaced by a directory in the PATH variable
Create a kubernetes cluster:
kind create cluster
# the default kubernetes kind cluster is created
Check the created cluster:
#Example
root@proxy:~# kind get clusters
kind

Note: For further kind installation information refer the below link:

Kind Installer reference

Install kubectl

Download the latest release with the command:

curl -LO "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl"
sudo install -o root -g root -m 0755 kubectl /usr/local/bin/kubectl

If you do not have root access on the target system, you can still install kubectl to the ~/.local/bin directory:

chmod +x kubectl
mkdir -p ~/.local/bin/kubectl
mv ./kubectl ~/.local/bin/kubectl
# and then add ~/.local/bin/kubectl to $PATH

Test to ensure the version you installed is up-to-date:

kubectl version --client

For detail kubectl installation information refer the below link:
Kubectl Installation reference

The installation is tested on the kubectl version
Client Version: v1.22.4
Server Version: v1.21.1

Get all kubernetes object files required for delfin deployment:

git clone https://github.com/sodafoundation/examples.git
# examples/delfin-kubernetes/deploy directory contains all the object files of delfin k8s delpoyment

The default version of delfin used is v1.5.0 To use a specific version of delfin replace the tags of delfin image in delfin-api-deployment.yaml ,delfin-task-deployment.yaml, delfin-exporter-deployment.yaml and delfin-alert-deployment.yaml files to desired tag(optional) 

# replace tag with required tag in each of the above mentioned files
image: sodafoundation/delfin:<tag required>

Build image from source code manually(optional)

To build the delfin docker image, source code and Dockerfile are needed. Dockerfile contains instructions on how the image is built.
Download the source code of delfin:

git clone https://github.com/sodafoundation/delfin.git

Build Delfin image and get into local environment:

cd delfin
# this builds the whole delfin code into the image with name as sodafoundation/delfin with tag as mentioned and saves into local environment
# in the place of tag give the desired tag
docker build -t sodafoundation/delfin:<tag> .
cd ..

Run the docker images command to verify that the build was successful:

docker images

Output:

REPOSITORY                                                 TAG     IMAGE ID       CREATED          SIZE
sodafoundation/delfin                                      <tag>     25cfadb1bf28   10 seconds ago   652 MB

Now,load the image downloaded with the tag into the kind node

# replace tag with downloaded version
kind load docker-image sodafoundation/delfin:<tag>

Commands to bring up the delfin services:

All the object files get added to the kubernetes cluster

Create all configMaps

cd examples/delfin-kubernetes/deploy
kubectl apply -f configMap.yaml

Create all pods

Brings up the api,task,alert,exporter,redis and rabbitmq services of delfin

kubectl apply -f delfin-api-deployment.yaml
kubectl apply -f delfin-task-deployment.yaml
kubectl apply -f delfin-exporter-deployment.yaml
kubectl apply -f delfin-alert-deployment.yaml
kubectl apply -f redis-deployment.yaml
kubectl apply -f rabbitmq-deployment.yaml

Create the service objects

kubectl apply -f delfin-api-service.yaml
kubectl apply -f delfin-exporter-service.yaml
kubectl apply -f delfin-alert-service.yaml
kubectl apply -f redis-service.yaml
kubectl apply -f rabbitmq-service.yaml

Get all the deployed objects

kubectl get all

To monitor the performance metrics on prometheus

Open the configMap.yaml file

# Uncomment the line in configMap.yaml file
# For prometheus exporter only 
performance_exporters = PerformanceExporterPrometheus

Follow the below site:
https://devopscube.com/setup-prometheus-monitoring-on-kubernetes/

To send an API request to a service

Use node IP and node port of the service
Example:

#Run the GET API to get the registered storages.
curl -X GET http://<IP of k8s node>:<nodePort of delfin-api-service SVC>/v1/storages
#Will give all the registered storages

For accessing cluster from outside, endpoint should be set which can be connected from outside the cluster
Follow the below link:
https://kind.sigs.k8s.io/docs/user/quick-start/#creating-a-cluster

Deleting the delfin on k8s

Steps to delete all the delfin k8s objects and k8s cluster created.

Delete all the config Maps from files.

kubectl delete configmap delfin-config

Delete all pods

Navigate to examples/delfin-kubernetes/deploy directory.

kubectl delete -f delfin-api-deployment.yaml
kubectl delete -f delfin-task-deployment.yaml
kubectl delete -f delfin-exporter-deployment.yaml
kubectl delete -f delfin-alert-deployment.yaml
kubectl delete -f redis-deployment.yaml
kubectl delete -f rabbitmq-deployment.yaml

Delete the services

kubectl delete -f delfin-api-service.yaml
kubectl delete -f delfin-exporter-service.yaml
kubectl delete -f delfin-alert-service.yaml
kubectl delete -f redis-service.yaml
kubectl delete -f rabbitmq-service.yaml

Get all the deployed objects

kubectl get all
# no delfin objects should be present

To delete k8s cluster

kind delete cluster