Deployment¶

rollout¶

when we first create deployment, it performs a rollout with revision=1 === replicaSet-1
next, if deployment object is upgraded, new rollout happens with revision=2 === replicaSet-2
eg: updating label, image,etc
k set image deployment-1 c1=image:version --record=true
or, k edit deployment deployment-1 --record=true
- --record flag to save the command used to create/update a deployment against the revision number.
check rollout status
k rollout status deployment deployment-1 --> status for deployment, status of each replica/pod
k rollout history deployment deployment-1 --revision=1 --> show revision history
Also run : k decribe deploymnet and check events

Recreate
- scaling down replicas = 0, then scale up to replicas-count (eg: 5)
Rolling update (default)
- scale down replicas by 1, and scale up by 1.
- if there is error with while deployment, it won't scale down further to maintain app availability.
Blue green
- service (select pod by label L1) --> Deployment-object-1, blue>> RS >> POD/s (all has L1)
- Deployment-object-2, green >> RS >> POD/s (all has L2)
- once all pod in L2 are healthy
- update service to select pod by L2
canary
- route small traffic to deployment-canary's pod, usinf common label selector on service
- once looks ok, the delete canary
- rollout changes to primary-deploymnet object.