Kubernetes 101 : Updates or Rollouts
The deployment rollout:
A rollout for a deployment of pods is caused by a change in any parameter in the pod's template within the deployment Yaml file - .spec.template -
For example, if we change the labels or the container images in the pod's template, we will trigger a rollout.
Changes like scaling a deployment by changing the number of pod replicas, do not cause a rollout.
We could make the changes in the deployment Yaml file - for the image -and apply the changes: - this is the preferred way since any previous changes are recorded in the Yaml file - :
We apply the changes using the below command:
We could also change the pod's parameters - image of the container - of a deployment using the below command for example:
We can check the status of our rollout, using the below command:
We run the below command to check the newly deployed updated pods - with the new version of nginx - :
We will notice that our new updated pods have different names from the older ones that were replaced.