提取报错信息【 unknown field “spec.selector.replicas”】【 unknown field “spec.selector.template”】
[root@master ~]# kubectl apply -f nginx-deployment.yaml
Error from server (BadRequest): error when creating "nginx-deployment.yaml": Deployment in version "v1" cannot be handled as a Deployment: strict decoding error: unknown field "spec.selector.replicas", unknown field "spec.selector.template"
根据报错信息,排查一下nginx-deployment
YAML文件。
# nginx-deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deploy
namespace: default
labels:
chapter: first-app
spec:
selector:
matchLabels:
app: nginx
replicas: 2
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
ports:
- containerPort: 80
首先,使用YAML、YML在线编辑(校验)器校对一下此YAML文件格式是否正确。未发现异常。
其次,根据报错信息,定位到【unknown field “spec.selector.replicas”】【unknown field “spec.selector.template”】这两处的字段中的replicas
和template
这两个关键字。提示的大概意思是在spec.selector字段值里未找到这两个属性,属于未知属性。
通过运行kubectl explain deployment
查看其中字段属性位置包含关系情况。
[root@master ~]# kubectl explain deployment
KIND: Deployment
VERSION: apps/v1
DESCRIPTION:
Deployment enables declarative updates for Pods and ReplicaSets.
FIELDS:
apiVersion <string>
APIVersion defines the versioned schema of this representation of an
object. Servers should convert recognized schemas to the latest internal
value, and may reject unrecognized values. More info:
https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#resources
kind <string>
Kind is a string value representing the REST resource this object
represents. Servers may infer this from the endpoint the client submits
requests to. Cannot be updated. In CamelCase. More info:
https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#types-kinds
metadata <Object>
Standard object's metadata. More info:
https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
spec <Object>
Specification of the desired behavior of the Deployment.
status <Object>
Most recently observed status of the Deployment.
查看replicas层级关系kubectl explain deployment.spec
replicas
这一字段属于spec下一级。不应该在selector
这一字段的下级。
同理,template
这一字段也属于spec下一级,不应该在selector
这一字段的下级。
[root@master ~]# kubectl explain deployment.spec
KIND: Deployment
VERSION: apps/v1
RESOURCE: spec <Object>
DESCRIPTION:
Specification of the desired behavior of the Deployment.
DeploymentSpec is the specification of the desired behavior of the
Deployment.
FIELDS:
minReadySeconds <integer>
Minimum number of seconds for which a newly created pod should be ready
without any of its container crashing, for it to be considered available.
Defaults to 0 (pod will be considered available as soon as it is ready)
paused <boolean>
Indicates that the deployment is paused.
progressDeadlineSeconds <integer>
The maximum time in seconds for a deployment to make progress before it is
considered to be failed. The deployment controller will continue to process
failed deployments and a condition with a ProgressDeadlineExceeded reason
will be surfaced in the deployment status. Note that progress will not be
estimated during the time a deployment is paused. Defaults to 600s.
replicas <integer>
Number of desired pods. This is a pointer to distinguish between explicit
zero and not specified. Defaults to 1.
revisionHistoryLimit <integer>
The number of old ReplicaSets to retain to allow rollback. This is a
pointer to distinguish between explicit zero and not specified. Defaults to
10.
selector <Object> -required-
Label selector for pods. Existing ReplicaSets whose pods are selected by
this will be the ones affected by this deployment. It must match the pod
template's labels.
strategy <Object>
The deployment strategy to use to replace existing pods with new ones.
template <Object> -required-
Template describes the pods that will be created.
️修改完成后的nginx-deployment.yaml,如下:
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deploy
namespace: default
labels:
chapter: first-app
spec:
replicas: 2
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
ports:
- containerPort: 80
重新运行该YAML文件,运行成功。
[root@master ~]# kubectl apply -f nginx-deployment.yaml
deployment.apps/nginx-deploy created
[root@master ~]# kubectl get deployment
NAME READY UP-TO-DATE AVAILABLE AGE
nginx-deploy 0/2 2 0 26s
[root@master ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx-deploy-7759cfdc55-q4622 1/1 Running 0 33s
nginx-deploy-7759cfdc55-skcgp 1/1 Running 0 33s