Kubernetes pod naming convention

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I'm wondering if there is a proper naming convention for generated pod names in Kubernetes. By generated pod names I mean the name displayed in both kubectl get pods or, for instance, by querying the heapster api:

$ curl -s http://192.168.99.100:32416/api/v1/model/namespaces/kube-system/pods
[
"kube-addon-manager-minikube",
"kube-dns-v20-8gsbl",
"kubernetes-dashboard-tp9kc",
"heapster-kj8hh",
"influxdb-grafana-stg3s"
]

$ curl -s http://192.168.99.100:32416/api/v1/model/namespaces/default/pods
[
"my-nginx-2723453542-065rx"
]

If there is no convention (as it looks like) are there any scenario(s) in which the common format: pod name + 5 alpha-numeric chars is true?

kubernetes naming
4 Answers

Naming Convention:

When you create a Deployment, it creates a replicaset named as:

replica-set-name = <deployment-name>-<random-string>

The replicaset, in turn, creates the pods adding another random string* to them:

<replica-set-name>-<random-string>

Example:

$ kubectl create deploy nginx --image=nginx
deployment.apps/nginx created

$ kubectl scale --replicas=3 deploy/nginx 
deployment.extensions/nginx scaled

$ kubectl get replicaset
NAME                                     DESIRED   CURRENT   READY   AGE
nginx-554b9c67f9                         3         3         3       96s

$ kubectl get po
NAME                                           READY   STATUS    RESTARTS   AGE
nginx-554b9c67f9-c5cv4                         1/1     Running   0          74s
nginx-554b9c67f9-hjkjq                         1/1     Running   0          74s
nginx-554b9c67f9-wbwdm                         1/1     Running   0          2m7s

* Not random at all:

In fact, the "random strings" aren’t completely random at all.

To prevent “bad words”, vowels and the numbers 0, 1 and 3 were removed from the rand.String function (PRs for reference: #37225 and #50070).

So, the <random-string> will be composed by a combination of the following alphanumeric characters: bcdfghjklmnpqrstvwxz2456789.

user_76410780

If you use StatefulSets then the naming convention is:

|--- StatefulSets: < name >
│----------└─ Pod: < name >-< ordinal index >

e.g. postgresql-0

user_20362060
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