CI/CD Set Up

This tutorial will walk you through on how to setup CI/CD

Topics covered:

Overview

Terraform helps you build a graph of all your resources and parallelizes the creation or modification of any non-dependent resources. Thus, Terraform builds infrastructure as efficiently as possible while providing the operators with clear insight into the dependencies on the infrastructure.

Pre-requisites

GitHub Organization account
Fork the repos below to your GitHub Organization account
- https://github.com/egovernments/DIGIT-DevOps
- https://github.com/egovernments/CIOps
AWS KMS
Go lang (version 1.13.X)
SOPS
GitHub user
Docker Hub account
AWS account with admin access to provision EKS Service. Try subscribing to a free AWS account to learn the basics. There is a limit on what is offered as free. This demo requires a commercial subscription to the EKS service. The cost for a one or two days trial might range between Rs 500-1000. (Note: Post the demo, for the internal folks, eGov will provide a 2-3 hrs time-bound access to eGov's AWS account based on the request and the available number of slots per day).
Install kubectl on your local machine to interact with the Kubernetes cluster.
Install Helm to help package the services along with the configurations, environment, secrets, etc into a Kubernetes manifests.
Install terraform version (0.14.10) for the Infra-as-code (IaC) to provision cloud resources as code and with desired resource graph. It also helps destroy the cluster in one go.
Install AWS CLI on your local machine so that you can use AWS CLI commands to provision and manage the cloud resources on your account.
Install AWS IAM Authenticator to help authenticate your connection from your local machine and deploy DIGIT services.
Use the AWS IAM User credentials provided for the Terraform (Infra-as-code) to connect to the AWS account and provision the cloud resources.
- You will receive a Secret Access Key and Access Key ID. Save the keys.
- Open the terminal and run the command given below. The AWS CLI is already installed and the credentials are saved. (Provide the credentials, leave the region and output format blank).
```
aws configure --profile cicd-infra-account 

AWS Access Key ID []:<Your access key>
AWS Secret Access Key []:<Your secret key>
Default region name []: ap-south-1
Default output format []: text
```
- The above creates the following file on your machine as /Users/.aws/credentials.
```
[cicd-infra-account] 
aws_access_key_id=*********** 
aws_secret_access_key=****************************
```

Setup Details

Before we provision the cloud resources, we need to understand and be sure about what resources need to be provisioned by terraform to deploy CI/CD.

The following is the resource graph that we are going to provision using terraform in a standard way so that every time and for every environment, the infra is the same.

EKS Control Plane (Kubernetes master)
Work node group (VMs with the estimated number of vCPUs, Memory)
EBS Volumes (Persistent volumes)
VPCs (Private networks)
Users to access, deploy and read-only

Terraform Script Resource Graph

Ideally, one would write the terraform script from scratch using this doc.
Here we have already written the terraform script that provisions the production-grade DIGIT Infra and can be customized with the specified configuration.
Clone the DIGIT-DevOps GitHub repo. The terraform script to provision the EKS cluster is available in this repo. The structure of the files is given below.

git clone --branch release https://github.com/egovernments/DIGIT-DevOps.git
cd DIGIT-DevOps/infra-as-code/terraform


└── modules
    ├── kubernetes
    │   └── aws
    │       ├── eks-cluster
    │       │   ├── main.tf
    │       │   ├── outputs.tf
    │       │   └── variables.tf
    │       ├── network
    │       │   ├── main.tf
    │       │   ├── outputs.tf
    │       │   └── variables.tf
    │       └── workers
    │           ├── main.tf
    │           ├── outputs.tf
    │           └── variables.tf
    └── storage
        └── aws
            ├── main.tf
            ├── outputs.tf
            └── variables.tf

Here, you will find the main.tf under each of the modules that have the provisioning definition for resources like EKS cluster, storage, etc. All these are modularized and react as per the customized options provided.

Example:

VPC Resources -
- VPC
- Subnets
- Internet Gateway
- Route Table
EKS Cluster Resources -
- IAM Role to allow EKS service to manage other AWS services
- EC2 Security Group to allow networking traffic with the EKS cluster
- EKS Cluster
EKS Worker Nodes Resources -
- IAM role allowing Kubernetes actions to access other AWS services
- EC2 Security Group to allow networking traffic
- Data source to fetch the latest EKS worker AMI
- AutoScaling launch configuration to configure worker instances
- AutoScaling group to launch worker instances
Storage Module -
- Configuration in this directory creates EBS volume and attaches it together.

The following main.tf with create s3 bucket to store all the states of the execution to keep track.

//DIGIT-DevOps/Infra-as-code/terraform/egov-cicd/remote-state

[**main.tf**](https://github.com/egovernments/DIGIT-DevOps/blob/release/infra-as-code/terraform/egov-cicd/remote-state/main.tf)\*\*\*\*

provider "aws" {
  region = "ap-south-1"
}

#This is a bucket name that you can name as you wish
resource "aws_s3_bucket" "terraform_state" {
  bucket = "try-cicd-workshop-yourname" 

  versioning {
    enabled = true
  }

  lifecycle {
    prevent_destroy = true
  }
}

#This is a bucket name that you can name as you wish
resource "aws_dynamodb_table" "terraform_state_lock" {
  name           = "try-cicd-workshop-yourname"
  read_capacity  = 1
  write_capacity = 1
  hash_key       = "LockID"

  attribute {
    name = "LockID"
    type = "S"
  }
}

The following main.tf contains the detailed resource definitions that need to be provisioned.

Dir: DIGIT-DevOps/Infra-as-code/terraform/egov-cicd

main.tf

terraform {
  backend "s3" {
    bucket = "try-cicd-workshop-yourname"
    key = "terraform"
    region = "ap-south-1"
  }
}

module "network" {
  source             = "../modules/kubernetes/aws/network"
  vpc_cidr_block     = "${var.vpc_cidr_block}"
  cluster_name       = "${var.cluster_name}"
  availability_zones = "${var.network_availability_zones}"
}


data "aws_eks_cluster" "cluster" {
  name = "${module.eks.cluster_id}"
}

data "aws_eks_cluster_auth" "cluster" {
  name = "${module.eks.cluster_id}"
}
  
provider "kubernetes" {
  host                   = "${data.aws_eks_cluster.cluster.endpoint}"
  cluster_ca_certificate = "${base64decode(data.aws_eks_cluster.cluster.certificate_authority.0.data)}"
  token                  = "${data.aws_eks_cluster_auth.cluster.token}"
  #load_config_file       = false
}
  
module "eks" {
  source          = "terraform-aws-modules/eks/aws"
  version         = "17.24.0"
  cluster_name    = "${var.cluster_name}"
  vpc_id          = "${module.network.vpc_id}"
  cluster_version = "${var.kubernetes_version}"
  subnets         = "${concat(module.network.private_subnets, module.network.public_subnets)}"

  worker_groups = [
    {
      name                          = "spot"
      subnets                       = "${concat(slice(module.network.private_subnets, 0, length(var.availability_zones)))}"
      override_instance_types       = "${var.override_instance_types}"
      kubelet_extra_args            = "--node-labels=node.kubernetes.io/lifecycle=spot"
      additional_security_group_ids = ["${module.network.worker_nodes_sg_id}"]
      asg_max_size                  = "${var.number_of_worker_nodes}"
      asg_desired_capacity          = "${var.number_of_worker_nodes}"
      spot_allocation_strategy      = "capacity-optimized"
      spot_instance_pools           = null
    }
  ]
  tags = "${
    tomap({
      "kubernetes.io/cluster/${var.cluster_name}" = "owned",
      "KubernetesCluster" = "${var.cluster_name}"
    })
  }"
 
}

module "jenkins" {

  source = "../modules/storage/aws"
  storage_count = 1
  environment = "${var.cluster_name}"
  disk_prefix = "jenkins-home"
  availability_zones = "${var.availability_zones}"
  storage_sku = "gp2"
  disk_size_gb = "50"
  
}

Custom Variables/Configurations

Define your configurations in variables.tf and provide the environment-specific cloud requirements. The same terraform template can be used to customize the configurations.

├── egov-cicd
│   ├── main.tf 
│   ├── outputs.tf
│   ├── providers.tf
│   ├── remote-state
│   │   └── main.tf
│   └── variables.tf

Following are the values that you need to mention in the following files. The blank ones will prompt for inputs during execution.

variables.tf

#
# Variables Configuration
#

variable "cluster_name" {
  default = "<Desired Cluster name>"  #eg: my-digit-cicd
}

variable "vpc_cidr_block" {
  default = "192.168.0.0/16"
}

variable "network_availability_zones" {
  default = ["ap-south-1b", "ap-south-1a"]
}

variable "availability_zones" {
  default = ["ap-south-1b"]
}

variable "kubernetes_version" {
  default = "1.18"
}

variable "instance_type" {
  default = "t3a.xlarge"
}

variable "override_instance_types" {
  default = ["t3.xlarge", "r5ad.xlarge", "r5a.xlarge", "t3a.xlarge"]
}

variable "number_of_worker_nodes" {
  default = "1"
}

variable "spot_max_price" {
  default = "0.0538"
}

variable "ssh_key_name" {
  default = "egov-cicd"
}

Run Terraform Scripts

We have covered what the terraform script does, the resources graph that it provisions and what custom values should be given with respect to the selected environment.

Now, run the terraform scripts to provision the infra required to Deploy DIGIT on AWS.

Use the 'cd' command to change to the following directory and run the following commands. Check the output.

cd DIGIT-DevOps/infra-as-code/terraform/egov-cicd/remote-state
terraform init
terraform plan
terraform apply


cd DIGIT-DevOps/infra-as-code/terraform/egov-cicd
terraform init
terraform plan
terraform apply

After successful execution, the following resources get created and can be verified by the command "terraform output".

s3 bucket: to store terraform state
Network: VPC, security groups
IAM users auth: using keybase to create admin, deployer, the user

Use the URL https://keybase.io/ to create your own PGP key. This creates both public and private keys on the machine, upload the public key into the keybase account that you have just created, give a name to it and ensure that you mention that in your terraform. This allows you to encrypt sensitive information.

Example: Create a user keybase. This is "egovterraform" in the case of eGov. Upload the public key here - https://keybase.io/egovterraform/pgp_keys.asc
Use this portal to Decrypt the secret key. To decrypt the PGP message, upload the PGP Message, PGP Private Key and Passphrase.
EKS cluster: with master(s) & worker node(s).
Storage(s): for es-master, es-data-v1, es-master-infra, es-data-infra-v1, zookeeper, kafka, kafka-infra.
Use this link to get the kubeconfig from EKS to fetch the kubeconfig file. This enables you to connect to the cluster from your local machine and deploy DIGIT services to the cluster.

aws sts get-caller-identity

# Run the below command and give the respective region-code and the cluster name
aws eks --region <region-code> update-kubeconfig --name <cluster_name>

Finally, verify that you are able to connect to the cluster by running the command below:

export KUBECONFIG=<path-to-your-kube_config>
kubectl config use-context <your cluster name>

kubectl get nodes

NAME                                             STATUS AGE   VERSION               OS-Image           
ip-192-168-xx-1.ap-south-1.compute.internal   Ready  45d   v1.18.10-eks-bac369   Amazon Linux 2

Whola! All set and now you can Deploy Jenkins

Jenkins Deployment

Post infra setup (Kubernetes Cluster), we start with deploying the Jenkins and kaniko-cache-warmer.

Pre-requisites

Sub domain to expose CI/CD URL
GitHub Oauth App (this provides you with the clientId, clientSecret)
- Under Authorization callback URL enter the below url ie (Replace <domain_name> with your domain) https://<domain_name>/securityRealm/finishLogin
Github User
Generate a new ssh key for the above user (this provides the ssh public and private keys)
Add the earlier created ssh public key to GitHub user account
Add ssh private key to the gitReadSshPrivateKey
With previously created GitHub users generate a personal read-only access token
Docker hub account details (username and password)
SSL certificate for the sub-domain

Prepare an <ci.yaml> master config file and <ci-secrets.yaml>. Name this file as desired. It has the following configurations:

credentials, secrets (you need to encrypt using sops and create a ci-secret.yaml separately)
Add subdomain name in ci.yaml
Check and add your project specific ci-secrets.yaml details (like github Oauth app clientId, clientSecret, gitReadSshPrivateKey, gitReadAccessToken, dockerConfigJson, dockerUsername and dockerPassword)
To create a Jenkins namespace mark this flag true
Add your environment-specific kubconfigs under kubConfigs like https://github.com/egovernments/DIGIT-DevOps/blob/release/config-as-code/environments/ci-demo-secrets.yaml#L50
KubeConfig environment name and deploymentJobs name from ci.yaml should be the same
Update the CIOps and DIGIT-DevOps repo ssh url with the forked repo's ssh url.
Make sure earlier created github users have read-only access to the forked DIGIT-DevOps and CIOps repos.
SSL certificate for the sub-domain.

Prepare CIOps Configs

Update the DOCKER_NAMESPACE with your docker hub organization name.
Update the repo name "egovio" with your docker hub organization name in buildPipeline.groovy
Update the cache repo name https://github.com/egovernments/CIOps/blob/master/vars/buildPipeline.groovy#L166 https://github.com/egovernments/CIOps/blob/master/vars/buildPipeline.groovy#L185
Remove the below env:
Remove the below volumeMounts:
- https://github.com/egovernments/CIOps/blob/master/vars/buildPipeline.groovy#L60-L61
- https://github.com/egovernments/CIOps/blob/master/vars/deployer.groovy#L20-L21
Remove the below volume:
- https://github.com/egovernments/CIOps/blob/master/vars/buildPipeline.groovy#L80-L87
- https://github.com/egovernments/CIOps/blob/master/vars/deployer.groovy#L32-L39

cd DIGIT-DevOps/deploy-as-code/deployer

export KUBECONFIG=<path-to-your-kube_config>
kubectl config use-context <your cluster name>
go run main.go deploy -c -e ci 'jenkins,kaniko-cache-warmer,nginx-ingress,cert-manager'

Jenkins is launched. You can access the same through your sub-domain configured in ci.yaml.

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Last updated 8 months ago