Переименование узлов Kubernetes Cluster


Делаю: 09.04.2019


По материалам из видео индуса:

https://www.youtube.com/watch?v=TqoA9HwFLVU&list=PL34sAs7_26wNBRWM6BDhnonoA5FMERax0&index=18


Подготовили кластер и окружение как здесь.


Renaming Kubernetes Nodes

$ kubectl get nodes
NAME         STATUS   ROLES    AGE   VERSION
master.k8s   Ready    master   92m   v1.14.1
node1.k8s    Ready    <none>   90m   v1.14.1
node2.k8s    Ready    <none>   87m   v1.14.1


$ kubectl run nginx --image nginx --replicas=2


$ kubectl get all -o wide
NAME                         READY   STATUS    RESTARTS   AGE   IP           NODE        NOMINATED NODE   READINESS GATES
pod/nginx-7db9fccd9b-8thfw   1/1     Running   0          28s   10.244.2.4   node2.k8s   <none>           <none>
pod/nginx-7db9fccd9b-jvhsp   1/1     Running   0          28s   10.244.1.5   node1.k8s   <none>           <none>

NAME                 TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE   SELECTOR
service/kubernetes   ClusterIP   10.96.0.1    <none>        443/TCP   93m   <none>

NAME                    READY   UP-TO-DATE   AVAILABLE   AGE   CONTAINERS   IMAGES   SELECTOR
deployment.apps/nginx   2/2     2            2           28s   nginx        nginx    run=nginx

NAME                               DESIRED   CURRENT   READY   AGE   CONTAINERS   IMAGES   SELECTOR
replicaset.apps/nginx-7db9fccd9b   2         2         2       28s   nginx        nginx    pod-template-hash=7db9fccd9b,run=nginx


// Пароль: kubeadmin
$ ssh root@node1.k8s

# hostnamectl set-hostname kubeworker1.example.com

# reboot


$ ssh root@node1.k8s

# vi /etc/hosts
192.168.0.11 kubeworker1.example.com kubeworker1


$ kubectl delete node node1.k8s


[root@kubeworker1 ~]# kubeadm reset
[Y]


$ ssh root@master.k8s

# kubeadm token create --print-join-command
kubeadm join 192.168.0.10:6443 --token gl09a3.jnrvo3z6kprgii3p     --discovery-token-ca-cert-hash sha256:c25162d5fdc412f95e4180552f18e305c006f22e281c6318098ef8b480543abf


Выполняю ее на [root@kubeworker1 ~]


$ kubectl get nodes
NAME                      STATUS   ROLES    AGE    VERSION
kubeworker1.example.com   Ready    <none>   96s    v1.14.1
master.k8s                Ready    master   113m   v1.14.1
node2.k8s                 Ready    <none>   108m   v1.14.1


$ kubectl run nginx --image nginx --replicas=2

$ kubectl scale deploy nginx --replicas=4


$ kubectl get pods -o wide
NAME                     READY   STATUS    RESTARTS   AGE   IP           NODE                      NOMINATED NODE   READINESS GATES
nginx-7db9fccd9b-8thfw   1/1     Running   0          24m   10.244.2.4   node2.k8s                 <none>           <none>
nginx-7db9fccd9b-d4nxg   1/1     Running   0          15m   10.244.2.5   node2.k8s                 <none>           <none>
nginx-7db9fccd9b-r8m2p   1/1     Running   0          9s    10.244.3.3   kubeworker1.example.com   <none>           <none>
nginx-7db9fccd9b-zgtvf   1/1     Running   0          9s    10.244.3.2   kubeworker1.example.com   <none>           <none>


Еще один способ. Вроде хуже

// Ошибка
$ kubectl drain node2.k8s

$ kubectl drain node2.k8s --ignore-daemonsets


$ ssh root@node2.k8s
# kubeadm reset
[Y]


# vi /usr/lib/systemd/system/kubelet.service.d/10-kubeadm.conf

Добавил в конец после EXTRA_ARGS параметр --hostname-override=kubeworker2.example.com


# systemctl daemon-reload


# kubeadm reset
[Y]


// Ранее показано как получить
# kubeadm token create --print-join-command
kubeadm join 192.168.0.10:6443 --token gl09a3.jnrvo3z6kprgii3p     --discovery-token-ca-cert-hash sha256:c25162d5fdc412f95e4180552f18e305c006f22e281c6318098ef8b480543abf


$ kubectl get nodes
NAME                      STATUS                        ROLES    AGE    VERSION
kubeworker1.example.com   Ready                         <none>   23m    v1.14.1
kubeworker2.example.com   Ready                         <none>   48s    v1.14.1
master.k8s                Ready                         master   134m   v1.14.1
node2.k8s                 NotReady,SchedulingDisabled   <none>   130m   v1.14.1


$ kubectl delete node node2.k8s