anchor.diff:      Howdy World!
   +
   The output now shows `v2` version of the image is being used.
  -+
  -. Delete resources:
  -
  -    kubectl delete deployment/app-rolling svc/app-rolling
   
   == Rollback
   
  +More details about 
  +
  +== Delete resources
  +
  +Delete resources created in this chapter:
  +
  +    kubectl delete deployment/app-recreate svc/app-recreate deployment/app-rolling svc/app-rolling
  
positive.code: 
  Let's look at these two deployment strategies.
  
  For our usecase, the application initially uses the image `arungupta/app-upgrade:v1`. Then the Deployment is updated to use the image `arungupta/app-upgrade:v2`. The v1 image prints "`Hello World!`". The v2 image prints "`Howdy World!`". The source code for these images is in the link:images[] directory.
  
  == Pre-requisites
  
  A 3 master nodes and 5 worker nodes cluster as explained at link:../cluster-install##multi-master-multi-node-multi-az-gossip-based-cluster[] is used for this chapter. A smaller cluster may be used.
  
  All configuration files for this chapter are in the `app-upgrade` directory.
  
  == Recreate strategy
  
  All existing pods are killed before the new ones are created. The configuration file looks like:
  
  
negative.code:     Annotations:              <none>
      Selector:                 name=app-recreate
      Type:                     LoadBalancer
      IP:                       100.65.43.233
      LoadBalancer Ingress:     af2dc1f99bda211e791f402037f18a54-1616925381.eu-central-1.elb.amazonaws.com
      Port:                     <unset>  80/TCP
      TargetPort:               80/TCP
      NodePort:                 <unset>  30158/TCP
      Endpoints:                100.96.1.14:80,100.96.2.13:80,100.96.3.13:80 + 2 more...
      Session Affinity:         None
      External Traffic Policy:  Cluster
      Events:
        Type    Reason                Age   From                Message
        ----    ------                ----  ----                -------
        Normal  CreatingLoadBalancer  24s   service-controller  Creating load balancer
        Normal  CreatedLoadBalancer   23s   service-controller  Created load balancer
  
  . Acccess service:
  
      $ curl http://af2dc1f99bda211e791f402037f18a54-1616925381.eu-central-1.elb.amazonaws.com
      Hello World!
  +
  The output shows that `v1` version of the image is being used.
  