如何修改/设置kubernetes的默认节点?

Question

我正在尝试从这个链接安装RabbitMQ操作符在K8S集群

我在我们的环境

上创建了以下设置

例子

K8S Control Plane (Cent OS)   - 192.168.1.2
Worker Node - 1   (Cent OS)   - 192.168.1.3
Worker Node - 2   (WindowS)   - 192.168.1.4

当我默认执行kubectl apply -f https://github.com/rabbitmq/cluster-operator/releases/latest/download/cluster-operator.yml时，它会尝试安装RabbitMQ on Windows Node

由于RabbitMQ操作符YAML文件太大，我不确定在哪里和所有nodeSelector应该更改

然而，我想安装RabbitMQ on Linux node，我不知道如何更改/设置Kubernetes的默认节点

编辑

[root@re-ctrl1 ~]# kubectl get nodes -o wide --show-labels
NAME                                    STATUS   ROLES                  AGE   VERSION   INTERNAL-IP    EXTERNAL-IP   OS-IMAGE                       KERNEL-VERSION          CONTAINER-RUNTIME   LABELS
re-devcentos                            Ready    <none>                 83d   v1.21.0   192.168.1.3    <none>        CentOS Linux 7 (Core)          3.10.0-862.el7.x86_64   docker://1.13.1     beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=re-devcentos,kubernetes.io/os=linux
re-ctrl1                                Ready    control-plane,master   91d   v1.21.0   192.168.1.2    <none>        CentOS Linux 7 (Core)          3.10.0-862.el7.x86_64   docker://20.10.6    beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/arch=amd64,kubernetes.io/hostname=re-ctrl1,kubernetes.io/os=linux,node-role.kubernetes.io/control-plane=,node-role.kubernetes.io/master=,node.kubernetes.io/exclude-from-external-load-balancers=
win-lj7gtbktpgg                         Ready    <none>                 8d    v1.21.1   192.168.1.4    <none>        Windows Server 2019 Standard   10.0.17763.2061         docker://20.10.7    beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=windows,kubernetes.io/arch=amd64,kubernetes.io/hostname=win-lj7gtbktpgg,kubernetes.io/os=windows,node.kubernetes.io/windows-build=10.0.17763

Answer 1

在您的node标签中，有一个有用的标签称为kubernetes.io/os=linux，您应该使用此标签来调度节点上的pod。

例如:(部分文件)....

apiVersion: apps/v1
kind: Deployment
metadata:
labels:
app.kubernetes.io/component: rabbitmq-operator
app.kubernetes.io/name: rabbitmq-cluster-operator
app.kubernetes.io/part-of: rabbitmq
name: rabbitmq-cluster-operator
namespace: rabbitmq-system
spec:
replicas: 1
selector:
matchLabels:
app.kubernetes.io/name: rabbitmq-cluster-operator
template:
metadata:
labels:
app.kubernetes.io/component: rabbitmq-operator
app.kubernetes.io/name: rabbitmq-cluster-operator
app.kubernetes.io/part-of: rabbitmq
spec:
nodeSelector:
kubernetes.io/os: linux #<----this is making deployment's pod to choose node with this label. 
containers:
- command:
- /manager
env:
- name: OPERATOR_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
image: rabbitmqoperator/cluster-operator:1.8.0
name: operator
ports:

Answer 2

您可以使用相同的多个选项，您可以使用节点选择器，节点关联&taint-toleration .

节点亲缘性是pod的一种属性，它将它们吸引到一组节点(作为首选项或硬性要求)。污点则相反——它们允许节点排斥一组pod。

https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/affinity-and-anti-affinity

apiVersion: v1
kind: Pod
metadata:
name: with-node-affinity
spec:
affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: kubernetes.io/e2e-az-name
operator: In
values:
- e2e-az1
- e2e-az2
preferredDuringSchedulingIgnoredDuringExecution:
- weight: 1
preference:
matchExpressions:
- key: another-node-label-key
operator: In
values:
- another-node-label-value
containers:
- name: with-node-affinity
image: k8s.gcr.io/pause:2.0

对于rabbitMQ，它可以像

apiVersion: apps/v1beta1
kind: StatefulSet
metadata:
name: rabbitmq
spec:
replicas: 1
serviceName: rabbitmq
selector:
matchLabels:
app: rabbitmq
template:
metadata:
labels:
app: rabbitmq
spec:
affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: kubernetes.io/os
operator: In
values:
- linux
- ubuntu
containers:
- name: rabbitmq
image: rabbitmq:3-management
env:
- name: "RABBITMQ_ERLANG_COOKIE"
value: "dsfsadfsfsd+0t36lQ="
volumeMounts:
- mountPath: /var/lib/rabbitmq
name: rabbitmq-data
volumes:
- name: rabbitmq-data
hostPath:
path: /data/rabbitmq
type: DirectoryOrCreate

污点,容错示例:https://kubernetes.io/docs/concepts/scheduling-eviction/taint-and-toleration/