AppOps with Kubernetes and Devtron - The Perfect Fit

Kubernetes needs no introduction in this cloud-native world. It was born when I was a middle-aged man. Years later, I am still as young as earlier (take with a pinch of salt) while Kubernetes grew out to be a fine tool that outperformed other platforms in enabling operational efficiency and application resilience. 

In the past, I wrote several articles and guides on Kubernetes and supported platforms. But then, in the pursuit of appyness, there is no end to innovation. 

In this article today, I take up another interesting use-case of Devtron as an open-source platform that refactors the Kubernetes ecosystem into an easy-to-use AppOps model. 

First, a few basics. 

What Are We Trying to Achieve?

Exploring the Devtron platform to validate its capabilities to build, deploy and manage apps on a K8s cluster. 

What is Devtron?

Devtron is an open-source, GUI based platform to deploy and manage Kubernetes applications. The platform allows you to manage an entire application ecosystem through a single control pane that spans across multiple cloud service providers with varying environments. While doing so, efficient collaboration and security sits at its core to naturally enable a DevOps model.

Let's get a hands on. 

Stage 1: Creating an Amazon EKS Cluster

We will start with configuring an AWS EKS cluster (you may also use a GKE or AKS cluster as per your choice). In case you already have a cluster setup, you may skip over to Stage 2.

Part One: Installing the AWS CLI

To work with AWS on the command line, you need to install the AWS CLI, that enables the creation and management of AWS services from a Linux, macOS, or Windows console. If you’re logged into the AWS console, you can spin up the AWS CloudShell, which comes preinstalled with the AWS CLI.

To install AWS CLI on Linux, log into your Linux operating system and access the console.

1. Fetch the latest AWS CLI version for Linux-x86(64-bit) platform.

$ curl "https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip" -o "awscliv2.zip"

$ unzip awscliv2.zip

$ sudo ./aws/install

$ aws --version

1. Fetch the latest version of eksctl.

$ curl --silent --location "https://github.com/weaveworks/eksctl/releases/latest/download/eksctl_$(uname -s)_amd64.tar.gz" | tar xz -C /tmp

$ sudo mv /tmp/eksctl /usr/local/bin

$ eksctl version
0.40.0

1. The next step is to deploy an Amazon EKS cluster. To do so, use the create cluster command, that sets up all the required resources.

$ eksctl create cluster \
--name devtron-darwin-cluster \
--region us-east-2 \
--nodegroup-name devtron-darwin-nodegroup \
--node-type t2.micro \
--nodes 4 \
--nodes-min 1 \
--nodes-max 5 \
--managed

• a given name, 
• region,
• nodegroup-name,
• node-type, nodes,
• minimum nodes and maximum nodes of the node group,
• and then deploys the cluster on a managed node group type.

1. Fetch the kubectl tool for Kubernetes version 1.18. Note that there are different links available for lower or higher versions, however, to use Devtron, version 1.18 or above is recommended.

$ curl -o kubectl https://amazon-eks.s3.us-west-2.amazonaws.com/1.18.9/2020-11-02/bin/linux/a

md64/kubectl

$ chmod +x ./kubectl

$ mkdir -p $HOME/bin && cp ./kubectl $HOME/bin/kubectl && export PATH=$PATH:$HOME/bin

$ kubectl version --short --client

Client Version: v1.18.9-eks-d1db3c

$ kubectl get service

NAME         TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE
kubernetes   ClusterIP   10.100.0.1   <none>        443/TCP   33d

Stage 2: Installing Devtron

1. Start by changing the Kubernetes context to the EKS cluster that you want to use, change the region and cluster name values to those specific to your environment.

$ aws eks --region us-east-2 update-kubeconfig --name 

darwin-devtron-cluster02

$ kubectl create namespace devtroncd

$ curl -fsSL -o get_helm.sh https://raw.githubusercontent.com/helm/helm/master/scripts/get-helm-3

$ chmod 700 get_helm.sh

$ ./get_helm.sh

$ sudo yum -y install openssl

$ helm version

WARNING: Kubernetes configuration file is group-readable. This is insecure. Location: /home/cloudshell-user/.kube/config
WARNING: Kubernetes configuration file is world-readable. This is insecure. Location: /home/cloudshell-user/.kube/config
version.BuildInfo{Version:"v3.5.3", GitCommit:"041ce5a2c17a58be0fcd5f5e16fb3e7e95fea622", GitTreeState:"dirty",

GoVersion:"go1.15.8"}

$ helm repo add devtron https://helm.devtron.ai

$ helm install devtron devtron/devtron-operator --namespace devtroncd --set secrets.POSTGRESQL_PASSWORD=new-password-here

$ kubectl get pod -n devtroncd

$ kubectl logs -f inception-849d647c4d-ldncs -n devtroncd

$ kubectl -n devtroncd get installers installer-devtron -o jsonpath='{.status.sync.status}'

Applied[cloudshell-user@ip-10-0-XX-XX ~]$

$ kubectl get pods -n devtroncd

$ kubectl -n devtroncd get secret devtron-secret -o jsonpath='{.data.ACD_PASSWORD}' | base64 -d 
argocd-server-59XXXXX-XXXX[cloudshell-user@ip-10-0-XX-XX ~]$

xxxxxxxxxx

$ kubectl get svc -n devtroncd

devtron-grafana                       ClusterIP      10.100.159.169                         

devtron-kubernetes-external-secrets   ClusterIP      10.100.171.60                        

devtron-minio                         ClusterIP      10.100.230.236                      

devtron-minio-svc                     ClusterIP      None                                                                                                    

devtron-nats                          ClusterIP      10.100.195.145                                                                                          

devtron-nats-mgmt                     ClusterIP      None                                                                                 

devtron-service                       LoadBalancer   10.100.204.202   a4777dd57858a4dc59afb0a4517b1748-XXXXXXXXXX.us-east-2.elb.amazonaws.com

PS: Dashboard URL above is edited for security purposes. 

$ kubectl -n devtroncd get secret devtron-secret -o jsonpath='{.data.ACD_PASSWORD}' | base64 -d

1. In the Devtron dashboard, click on the Global Configurations button at the bottom left and select the option Host URL.

1. To add a GitOps account, click on the GitOps tab on the left of your global configurations screen and add the Github organization and access credentials. 
2. Add the Git Host, the Github organization name, Git access credentials, and then click Save.

1. Click on add git account, Name to your Git provider, set the URL, Authentication type, the Git Username, Password, and then click Save.

1. Click Add docker registry, set the Registry name, the Registry type (in our case its ECR), add the Registry URL, the AWS region, the Amazon IAM role access Id, Secret access key, and then click Save.

1. On the Devtron dashboard, click on the Applications tab; this will bring up a display with a button Add New App at the top right of the screen, click on the button.

1. To enable Continuous Integration, we need to add a new workflow to our application. Click add a New Workflow, give the workflow a Name and click Save.

1. Select the Trigger tab to view your available workflows. Click Select Image on the deploy step to trigger the deployment using the deployment strategy that we defined, and the pipeline will display as Progressing.

1. If an earlier Installation of Devtron failed on the cluster, you might receive errors in case you try to re-install Devtron. Make sure to look at the errors that are being thrown from the inception pod. You can quickly check the logs using the command below.

 $ kubectl logs -f inception-d95bc9478-7blw6 -n devtroncd

$ pod=$(kubectl -n devtroncd get po -l app=inception -o jsonpath='{.items[0].metadata.name}')&& kubectl -n devtroncd logs -f $pod

$ cd devtron-installation-script/
$ kubectl delete -n devtroncd -f yamls/
$ kubectl delete -n devtroncd -f charts/devtron/templates/devtron-installer.yaml
$ kubectl delete -n devtroncd -f charts/devtron/templates/install.yaml
$ kubectl delete -n devtroncd -f charts/devtron/crds
$ kubectl delete ns devtroncd

$ cd devtron-installation-script/
$ kubectl delete -n devtroncd -f yamls/
$ kubectl -n devtroncd patch installer installer-devtron --type json -p '[{"op": "remove", "path": "/status"}]'

    1. To resolve the issue, run the commands below to upgrade your Devtron installation.

$ helm repo update
$ helm upgrade devtron devtron/devtron-operator -n devtroncd

$ kubectl -n devtroncd get installers installer-devtron -o jsonpath='{.status.sync.status}'

$ kubectl logs -f git-sensor-0 -n devtroncd