In Kubernetes, how to set pods' names when using replication controllers?

Question

I have a simple replication controller yaml file which looks like this:

apiVersion: v1
kind: ReplicationController
metadata:
  name: nginx
spec:
  replicas: 3
  selector:
    app: nginx
  template:
    spec:
      containers:
      - image: library/nginx:3.2
        imagePullPolicy: IfNotPresent
        name: nginx
        ports:
        - containerPort: 80
    metadata:
      labels:
        app: nginx

And after running this replication controller, I will get 3 different pods whose names are "nginx-xxx", where "xxx" represents a random string of letters and digits.

What I want is to specify names for the pods created by the replication controller, so that the pods' name can be "nginx-01", "nginx-02", "nginx-03". And further more, for say if pod "nginx-02" is down for some reason, and replication controller will automatically create another nginx pod, and I want this new nginx pod's name to remain as "nginx-02".

I wonder if this is possible? Thanks in advance.

Answer 1

This can be implemented using statefulsets which is out of beta since version 1.9. Quoting the documentation: When using kind: StatefulSet,

Pods have a unique identity that is comprised of an ordinal, a stable network identity, and stable storage. The identity sticks to the Pod, regardless of which node it’s (re)scheduled on.

Each Pod in a StatefulSet derives its hostname from the name of the StatefulSet and the ordinal of the Pod. The pattern for the constructed hostname is $(statefulset name)-$(ordinal).

So in the example above, you would get nginx-0,nginx-1,nginx-2