Deploy Canary Set Up

Clone the repository

cd ~/environment
git clone https://github.com/aws-containers/eks-microservice-demo.git
cd eks-microservice-demo

Create a namespace and a mesh

kubectl apply -f flagger/mesh.yaml
  
namespace/flagger created
mesh.appmesh.k8s.aws/flagger created

Create a deployment and a horizontal pod autoscaler

export APP_VERSION=1.0
envsubst < ./flagger/flagger-app.yaml | kubectl apply -f -
  
horizontalpodautoscaler.autoscaling/detail created
deployment.apps/detail created  

Create IAM policy and Role for flagger-loadtester

# Create an IAM policy called AWSAppMeshK8sControllerIAMPolicy
aws iam create-policy \
    --policy-name FlaggerEnvoyNamespaceIAMPolicy \
    --policy-document file://envoy-iam-policy.json

# Create an IAM service account for flagger namespace
 eksctl create iamserviceaccount --cluster eksworkshop-eksctl \
  --namespace flagger \
  --name flagger-envoy-proxies \
  --attach-policy-arn arn:aws:iam::$ACCOUNT_ID:policy/FlaggerEnvoyNamespaceIAMPolicy \
  --override-existing-serviceaccounts \
  --approve

Deploy the load testing service to generate traffic during the canary analysis

helm upgrade -i flagger-loadtester flagger/loadtester \
  --namespace=flagger \
  --set appmesh.enabled=true \
  --set "appmesh.backends[0]=detail" \
  --set "appmesh.backends[1]=detail-canary" \
  --set "serviceAccountName=flagger-envoy-proxies"

Release "flagger-loadtester" does not exist. Installing it now.  
NAME: flagger-loadtester  
LAST DEPLOYED: Mon Mar 15 19:31:10 2021  
NAMESPACE: flagger
STATUS: deployed  
REVISION: 1
TEST SUITE: None  
NOTES:  
Flagger's load testing service is available at http://flagger-loadtester.flagger/  

Create a canary definition

Now let’s deploy the Flagger canary definition file for detail service

kubectl apply -f flagger/flagger-canary.yaml
  
canary.flagger.app/detail created

You can see the below objects being created by flagger

kubectl -n appmesh-system logs deploy/flagger --tail 15  -f | jq .msg

"Service detail-primary.flagger created"
"all the metrics providers are available!"
"VirtualNode detail-primary.flagger created"
"VirtualNode detail-canary.flagger created"
"VirtualRouter detail created"
"VirtualService detail created"
"VirtualRouter detail-canary created"
"VirtualService detail-canary created"
"Deployment detail-primary.flagger created"
"detail-primary.flagger not ready: waiting for rollout to finish: observed deployment generation less then desired generation"
"all the metrics providers are available!"
"Scaling down Deployment detail.flagger"
"HorizontalPodAutoscaler detail-primary.flagger created"
"Service detail.flagger created"
"Initialization done! detail.flagger"

You should see the below event from canary

kubectl -n flagger describe canary/detail
Events:                                                                                                                                             Type     Reason  Age                  From     Message                                                                                            ----     ------  ----                 ----     -------
Warning  Synced  2m24s                flagger  detail-primary.flagger not ready: waiting for rollout to finish: observed deployment generation less then desired generation
Normal   Synced  85s (x2 over 2m24s)  flagger  all the metrics providers are available!                                                           Normal   Synced  84s                  flagger  Initialization done! detail.flagger

After the bootstrap is completed,

  • detail deployment is scaled to zero.
  • Traffic to detail.flagger will be routed to the primary pods.
  • AppMesh resources like virtualnode, virtualservice, virtualrouter has been created for the detail service
kubectl get pod,deployment,svc,virtualnode,virtualservice,virtualrouter -n flagger
NAME                                      READY   STATUS    RESTARTS   AGE
pod/detail-primary-5f4cb44b79-xxxx      3/3     Running   0          3m58s
pod/detail-primary-5f4cb44b79-xxxx       3/3     Running   0          3m58s
pod/flagger-loadtester-5bdf76cfb7-yyyy   3/3     Running   0          5m35s

NAME                                 READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/detail               0/0     0            0           4m50s
deployment.apps/detail-primary       2/2     2            2           3m58s
deployment.apps/flagger-loadtester   1/1     1            1           5m35s

NAME                         TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)    AGE
service/detail               ClusterIP   10.100.xxx.104   <none>        3000/TCP   2m58s
service/detail-canary        ClusterIP   10.100.yyy.188   <none>        3000/TCP   3m59s
service/detail-primary       ClusterIP   10.100.zzz.217   <none>        3000/TCP   3m59s
service/flagger-loadtester   ClusterIP   10.100.pp.62     <none>        80/TCP     5m35s

NAME                                             ARN                                                                                          AGE
virtualnode.appmesh.k8s.aws/detail-canary        arn:aws:appmesh:us-east-2:$ACCOUNT_ID:mesh/flagger/virtualNode/detail-canary_flagger        3m59s
virtualnode.appmesh.k8s.aws/detail-primary       arn:aws:appmesh:us-east-2:$ACCOUNT_ID:mesh/flagger/virtualNode/detail-primary_flagger       3m59s
virtualnode.appmesh.k8s.aws/flagger-loadtester   arn:aws:appmesh:us-east-2:$ACCOUNT_ID:mesh/flagger/virtualNode/flagger-loadtester_flagger   5m35s

NAME                                           ARN                                                                                        AGE
virtualservice.appmesh.k8s.aws/detail          arn:aws:appmesh:us-east-2:$ACCOUNT_ID:mesh/flagger/virtualService/detail.flagger          3m58s
virtualservice.appmesh.k8s.aws/detail-canary   arn:aws:appmesh:us-east-2:$ACCOUNT_ID:mesh/flagger/virtualService/detail-canary.flagger   3m58s

NAME                                          ARN                                                                                       AGE
virtualrouter.appmesh.k8s.aws/detail          arn:aws:appmesh:us-east-2:$ACCOUNT_ID:mesh/flagger/virtualRouter/detail_flagger          3m58s
virtualrouter.appmesh.k8s.aws/detail-canary   arn:aws:appmesh:us-east-2:$ACCOUNT_ID:mesh/flagger/virtualRouter/detail-canary_flagger   3m58s

Testing the setup

Exec into flagger-loadtester pod

kubectl exec deploy/flagger-loadtester -n flagger -it -- bash
  
Defaulting container name to loadtester.
Use 'kubectl describe pod/flagger-loadtester-5bdf76cfb7-wl59d -n flagger' to see all of the containers in this pod.
bash-5.0$

Curl to detail service to confirm if you get a response from the deployed service

curl http://detail.flagger:3000/catalogDetail
{ "version": "1", "vendors": ["ABC.com"] }

Congratulations! You have set up the canary analysis for backend service detail successfully.