k8s实践5:细微处入手探索apiserver

1.
集群部署完成,整个组件全部正常运行.
etcd的数据,都可以通过api接口检索显示.
测试看看.

先看看apisever的地址

[root@k8s-master1 ~]# kubectl cluster-info
Kubernetes master is running at https://192.168.32.127:8443
CoreDNS is running at https://192.168.32.127:8443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy
To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.
[root@k8s-master1 ~]#

执行命令

[root@k8s-master1 ~]# curl https://192.168.32.127:8443
curl: (60) Peer's Certificate issuer is not recognized.
More details here: http://curl.haxx.se/docs/sslcerts.html

curl performs SSL certificate verification by default, using a "bundle"
of Certificate Authority (CA) public keys (CA certs). If the default
bundle file isn't adequate, you can specify an alternate file
using the --cacert option.
If this HTTPS server uses a certificate signed by a CA represented in
the bundle, the certificate verification probably failed due to a
problem with the certificate (it might be expired, or the name might
not match the domain name in the URL).
If you'd like to turn off curl's verification of the certificate, use
the -k (or --insecure) option.
[root@k8s-master1 ~]#

需要证书

证书存放目录

[root@k8s-master2 cert]# pwd
/etc/kubernetes/cert
[root@k8s-master2 cert]# ls
ca-config.json               kube-controller-manager-csr.json        kubelet.key
ca.csr                       kube-controller-manager-key.pem         kubernetes.csr
ca-csr.json                  kube-controller-manager.pem             kubernetes-csr.json
ca-key.pem                   kubelet-client-2019-02-28-11-16-54.pem  kubernetes-key.pem
ca.pem                       kubelet-client-current.pem              kubernetes.pem
kube-controller-manager.csr  kubelet.crt
[root@k8s-master2 cert]#

[root@k8s-master1 ~]# curl https://192.168.32.127:8443 --cacert /etc/kubernetes/cert/ca.pem --cert /etc/kubernetes/cert/kubernetes.pem --key /etc/kubernetes/cert/kubernetes-key.pem
{
  "kind": "Status",
  "apiVersion": "v1",
  "metadata": {

  },
  "status": "Failure",
  "message": "forbidden: User \"kubernetes\" cannot get path \"/\"",
  "reason": "Forbidden",
  "details": {

  },
  "code": 403
}[root@k8s-master1 ~]#

报错.没有用户kubernetes没有权限

2.
rbac权限问题处理

增加用户kubernetes权限

[root@k8s-master1 roles]# cat clusterroles1.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  annotations:
    rbac.authorization.kubernetes.io/autoupdate: "true"
  labels:
    kubernetes.io/bootstrapping: rbac-defaults
  name: discover_base_url
rules:
- nonResourceURLs:
  - /
  verbs:
  - get

[root@k8s-master1 roles]# cat clusterrolebindings1.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: discover-base-url
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: discover_base_url
subjects:
- apiGroup: rbac.authorization.k8s.io
  kind: User
  name: kubernetes
[root@k8s-master1 roles]#

3.

检索看看有哪些api.结果见下:

[root@k8s-master1 ~]# kubectl get apiservice
NAME                                   AGE
v1.                                    14d
v1.apps                                14d
v1.authentication.k8s.io               14d
v1.authorization.k8s.io                14d
v1.autoscaling                         14d
v1.batch                               14d
v1.networking.k8s.io                   14d
v1.rbac.authorization.k8s.io           14d
v1.storage.k8s.io                      14d
v1beta1.admissionregistration.k8s.io   14d
v1beta1.apiextensions.k8s.io           14d
v1beta1.apps                           14d
v1beta1.authentication.k8s.io          14d
v1beta1.authorization.k8s.io           14d
v1beta1.batch                          14d
v1beta1.certificates.k8s.io            14d
v1beta1.coordination.k8s.io            14d
v1beta1.events.k8s.io                  14d
v1beta1.extensions                     14d
v1beta1.policy                         14d
v1beta1.rbac.authorization.k8s.io      14d
v1beta1.scheduling.k8s.io              14d
v1beta1.storage.k8s.io                 14d
v1beta2.apps                           14d
v2beta1.autoscaling                    14d
v2beta2.autoscaling                    14d

显示更详细的,见下:

[root@k8s-master1 ~]# kubectl api-versions
admissionregistration.k8s.io/v1beta1
apiextensions.k8s.io/v1beta1
apiregistration.k8s.io/v1
apiregistration.k8s.io/v1beta1
apps/v1
apps/v1beta1
apps/v1beta2
authentication.k8s.io/v1
authentication.k8s.io/v1beta1
authorization.k8s.io/v1
authorization.k8s.io/v1beta1
autoscaling/v1
autoscaling/v2beta1
autoscaling/v2beta2
batch/v1
batch/v1beta1
certificates.k8s.io/v1beta1
coordination.k8s.io/v1beta1
events.k8s.io/v1beta1
extensions/v1beta1
networking.k8s.io/v1
policy/v1beta1
rbac.authorization.k8s.io/v1
rbac.authorization.k8s.io/v1beta1
scheduling.k8s.io/v1beta1
storage.k8s.io/v1
storage.k8s.io/v1beta1
v1
[root@k8s-master1 ~]#

[root@k8s-master1 ~]# curl https://192.168.32.127:8443/ --cacert /etc/kubernetes/cert/ca.pem --cert /etc/kubernetes/cert/kubernetes.pem --key /etc/kubernetes/cert/kubernetes-key.pem
{
  "paths": [
    "/api",
    "/api/v1",
    "/apis",
    "/apis/",
    "/apis/admissionregistration.k8s.io",
    "/apis/admissionregistration.k8s.io/v1beta1",
    "/apis/apiextensions.k8s.io",
    "/apis/apiextensions.k8s.io/v1beta1",
    "/apis/apiregistration.k8s.io",
    "/apis/apiregistration.k8s.io/v1",
    "/apis/apiregistration.k8s.io/v1beta1",
    "/apis/apps",
    "/apis/apps/v1",
    "/apis/apps/v1beta1",
    "/apis/apps/v1beta2",
    "/apis/authentication.k8s.io",
    "/apis/authentication.k8s.io/v1",
    "/apis/authentication.k8s.io/v1beta1",
    "/apis/authorization.k8s.io",
    "/apis/authorization.k8s.io/v1",
    "/apis/authorization.k8s.io/v1beta1",
    "/apis/autoscaling",
    "/apis/autoscaling/v1",
    "/apis/autoscaling/v2beta1",
    "/apis/autoscaling/v2beta2",
    "/apis/batch",
    "/apis/batch/v1",
    "/apis/batch/v1beta1",
    "/apis/certificates.k8s.io",
    "/apis/certificates.k8s.io/v1beta1",
    "/apis/coordination.k8s.io",
    "/apis/coordination.k8s.io/v1beta1",
    "/apis/events.k8s.io",
    "/apis/events.k8s.io/v1beta1",
    "/apis/extensions",
    "/apis/extensions/v1beta1",
    "/apis/networking.k8s.io",
    "/apis/networking.k8s.io/v1",
    "/apis/policy",
    "/apis/policy/v1beta1",
    "/apis/rbac.authorization.k8s.io",
    "/apis/rbac.authorization.k8s.io/v1",
    "/apis/rbac.authorization.k8s.io/v1beta1",
    "/apis/scheduling.k8s.io",
    "/apis/scheduling.k8s.io/v1beta1",
    "/apis/storage.k8s.io",
    "/apis/storage.k8s.io/v1",
    "/apis/storage.k8s.io/v1beta1",
    "/healthz",
    "/healthz/autoregister-completion",
    "/healthz/etcd",
    "/healthz/log",
    "/healthz/ping",
    "/healthz/poststarthook/apiservice-openapi-controller",
    "/healthz/poststarthook/apiservice-registration-controller",
    "/healthz/poststarthook/apiservice-status-available-controller",
    "/healthz/poststarthook/bootstrap-controller",
    "/healthz/poststarthook/ca-registration",
    "/healthz/poststarthook/generic-apiserver-start-informers",
    "/healthz/poststarthook/kube-apiserver-autoregistration",
    "/healthz/poststarthook/rbac/bootstrap-roles",
    "/healthz/poststarthook/scheduling/bootstrap-system-priority-classes",
    "/healthz/poststarthook/start-apiextensions-controllers",
    "/healthz/poststarthook/start-apiextensions-informers",
    "/healthz/poststarthook/start-kube-aggregator-informers",
    "/healthz/poststarthook/start-kube-apiserver-admission-initializer",
    "/healthz/poststarthook/start-kube-apiserver-informers",
    "/logs",
    "/metrics",
    "/openapi/v2",
    "/swagger-2.0.0.json",
    "/swagger-2.0.0.pb-v1",
    "/swagger-2.0.0.pb-v1.gz",
    "/swagger-ui/",
    "/swagger.json",
    "/swaggerapi",
    "/version"
  ]
}[root@k8s-master1 ~]#

这些api的区别是什么？

版本区别
beta版本
版本名称包含了 beta,比如apps/v1beta1.
这是测试版本.

Stable版本
版本名称中包含 vX 这里的X是一个整数,比如apiregistration.k8s.io/v1
这是稳定版本

回忆下,创建pod,svc时用的是什么api呢？

创建service,pod用的是v1
创建deployment,daemonsets用的是apps/v1beta1

比较小白,为什么这样用呢？svc用v1,deployment不用？为什么呢？

访问api,检索三个最常用的做对比,见下:

[root@k8s-master1 ~]# curl https://192.168.32.127:8443/api/v1 --cacert /etc/kubernetes/cert/ca.pem --cert /etc/kubernetes/cert/kubernetes.pem --key /etc/kubernetes/cert/kubernetes-key.pem
{
  "kind": "APIResourceList",
  "groupVersion": "v1",
  "resources": [
    {
      "name": "bindings",
      "singularName": "",
      "namespaced": true,
      "kind": "Binding",
      "verbs": [
        "create"
      ]
    },
    {
      "name": "componentstatuses",
      "singularName": "",
      "namespaced": false,
      "kind": "ComponentStatus",
      "verbs": [
        "get",
        "list"
      ],
      "shortNames": [
        "cs"
      ]
    },
    {
      "name": "configmaps",
      "singularName": "",
      "namespaced": true,
      "kind": "ConfigMap",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "cm"
      ]
    },
    {
      "name": "endpoints",
      "singularName": "",
      "namespaced": true,
      "kind": "Endpoints",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "ep"
      ]
    },
    {
      "name": "events",
      "singularName": "",
      "namespaced": true,
      "kind": "Event",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "ev"
      ]
    },
    {
      "name": "limitranges",
      "singularName": "",
      "namespaced": true,
      "kind": "LimitRange",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "limits"
      ]
    },
    {
      "name": "namespaces",
      "singularName": "",
      "namespaced": false,
      "kind": "Namespace",
      "verbs": [
        "create",
        "delete",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "ns"
      ]
    },
    {
      "name": "namespaces/finalize",
      "singularName": "",
      "namespaced": false,
      "kind": "Namespace",
      "verbs": [
        "update"
      ]
    },
    {
      "name": "namespaces/status",
      "singularName": "",
      "namespaced": false,
      "kind": "Namespace",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "nodes",
      "singularName": "",
      "namespaced": false,
      "kind": "Node",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "no"
      ]
    },
    {
      "name": "nodes/proxy",
      "singularName": "",
      "namespaced": false,
      "kind": "NodeProxyOptions",
      "verbs": [
        "create",
        "delete",
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "nodes/status",
      "singularName": "",
      "namespaced": false,
      "kind": "Node",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "persistentvolumeclaims",
      "singularName": "",
      "namespaced": true,
      "kind": "PersistentVolumeClaim",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "pvc"
      ]
    },
    {
      "name": "persistentvolumeclaims/status",
      "singularName": "",
      "namespaced": true,
      "kind": "PersistentVolumeClaim",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "persistentvolumes",
      "singularName": "",
      "namespaced": false,
      "kind": "PersistentVolume",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "pv"
      ]
    },
    {
      "name": "persistentvolumes/status",
      "singularName": "",
      "namespaced": false,
      "kind": "PersistentVolume",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "pods",
      "singularName": "",
      "namespaced": true,
      "kind": "Pod",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "po"
      ],
      "categories": [
        "all"
      ]
    },
    {
      "name": "pods/attach",
      "singularName": "",
      "namespaced": true,
      "kind": "PodAttachOptions",
      "verbs": [
        "create",
        "get"
      ]
    },
    {
      "name": "pods/binding",
      "singularName": "",
      "namespaced": true,
      "kind": "Binding",
      "verbs": [
        "create"
      ]
    },
    {
      "name": "pods/eviction",
      "singularName": "",
      "namespaced": true,
      "group": "policy",
      "version": "v1beta1",
      "kind": "Eviction",
      "verbs": [
        "create"
      ]
    },
    {
      "name": "pods/exec",
      "singularName": "",
      "namespaced": true,
      "kind": "PodExecOptions",
      "verbs": [
        "create",
        "get"
      ]
    },
    {
      "name": "pods/log",
      "singularName": "",
      "namespaced": true,
      "kind": "Pod",
      "verbs": [
        "get"
      ]
    },
    {
      "name": "pods/portforward",
      "singularName": "",
      "namespaced": true,
      "kind": "PodPortForwardOptions",
      "verbs": [
        "create",
        "get"
      ]
    },
    {
      "name": "pods/proxy",
      "singularName": "",
      "namespaced": true,
      "kind": "PodProxyOptions",
      "verbs": [
        "create",
        "delete",
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "pods/status",
      "singularName": "",
      "namespaced": true,
      "kind": "Pod",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "podtemplates",
      "singularName": "",
      "namespaced": true,
      "kind": "PodTemplate",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ]
    },
    {
      "name": "replicationcontrollers",
      "singularName": "",
      "namespaced": true,
      "kind": "ReplicationController",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "rc"
      ],
      "categories": [
        "all"
      ]
    },
    {
      "name": "replicationcontrollers/scale",
      "singularName": "",
      "namespaced": true,
      "group": "autoscaling",
      "version": "v1",
      "kind": "Scale",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "replicationcontrollers/status",
      "singularName": "",
      "namespaced": true,
      "kind": "ReplicationController",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "resourcequotas",
      "singularName": "",
      "namespaced": true,
      "kind": "ResourceQuota",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "quota"
      ]
    },
    {
      "name": "resourcequotas/status",
      "singularName": "",
      "namespaced": true,
      "kind": "ResourceQuota",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "secrets",
      "singularName": "",
      "namespaced": true,
      "kind": "Secret",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ]
    },
    {
      "name": "serviceaccounts",
      "singularName": "",
      "namespaced": true,
      "kind": "ServiceAccount",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "sa"
      ]
    },
    {
      "name": "services",
      "singularName": "",
      "namespaced": true,
      "kind": "Service",
      "verbs": [
        "create",
        "delete",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "svc"
      ],
      "categories": [
        "all"
      ]
    },
    {
      "name": "services/proxy",
      "singularName": "",
      "namespaced": true,
      "kind": "ServiceProxyOptions",
      "verbs": [
        "create",
        "delete",
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "services/status",
      "singularName": "",
      "namespaced": true,
      "kind": "Service",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    }
  ]
}[root@k8s-master1 ~]#

[root@k8s-master1 ~]# curl https://192.168.32.127:8443/apis/apps/v1 --cacert /etc/kubernetes/cert/a.pem --cert /etc/kubernetes/cert/kubernetes.pem --key /etc/kubernetes/cert/kubernetes-key.pem
{
  "kind": "APIResourceList",
  "apiVersion": "v1",
  "groupVersion": "apps/v1",
  "resources": [
    {
      "name": "controllerrevisions",
      "singularName": "",
      "namespaced": true,
      "kind": "ControllerRevision",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ]
    },
    {
      "name": "daemonsets",
      "singularName": "",
      "namespaced": true,
      "kind": "DaemonSet",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "ds"
      ],
      "categories": [
        "all"
      ]
    },
    {
      "name": "daemonsets/status",
      "singularName": "",
      "namespaced": true,
      "kind": "DaemonSet",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "deployments",
      "singularName": "",
      "namespaced": true,
      "kind": "Deployment",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "deploy"
      ],
      "categories": [
        "all"
      ]
    },
    {
      "name": "deployments/scale",
      "singularName": "",
      "namespaced": true,
      "group": "autoscaling",
      "version": "v1",
      "kind": "Scale",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "deployments/status",
      "singularName": "",
      "namespaced": true,
      "kind": "Deployment",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "replicasets",
      "singularName": "",
      "namespaced": true,
      "kind": "ReplicaSet",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "rs"
      ],
      "categories": [
        "all"
      ]
    },
    {
      "name": "replicasets/scale",
      "singularName": "",
      "namespaced": true,
      "group": "autoscaling",
      "version": "v1",
      "kind": "Scale",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "replicasets/status",
      "singularName": "",
      "namespaced": true,
      "kind": "ReplicaSet",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "statefulsets",
      "singularName": "",
      "namespaced": true,
      "kind": "StatefulSet",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ],
      "shortNames": [
        "sts"
      ],
      "categories": [
        "all"
      ]
    },
    {
      "name": "statefulsets/scale",
      "singularName": "",
      "namespaced": true,
      "group": "autoscaling",
      "version": "v1",
      "kind": "Scale",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    },
    {
      "name": "statefulsets/status",
      "singularName": "",
      "namespaced": true,
      "kind": "StatefulSet",
      "verbs": [
        "get",
        "patch",
        "update"
      ]
    }
  ]
}[root@k8s-master1 ~]#

[root@k8s-master2 ~]# curl https://192.168.32.127:8443/apis/rbac.authorization.k8s.io/v1 --cacert etc/kubernetes/cert/ca.pem --cert /etc/kubernetes/cert/kubernetes.pem --key /etc/kubernetes/cert/kubernetes-key.pem
{
  "kind": "APIResourceList",
  "apiVersion": "v1",
  "groupVersion": "rbac.authorization.k8s.io/v1",
  "resources": [
    {
      "name": "clusterrolebindings",
      "singularName": "",
      "namespaced": false,
      "kind": "ClusterRoleBinding",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ]
    },
    {
      "name": "clusterroles",
      "singularName": "",
      "namespaced": false,
      "kind": "ClusterRole",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ]
    },
    {
      "name": "rolebindings",
      "singularName": "",
      "namespaced": true,
      "kind": "RoleBinding",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ]
    },
    {
      "name": "roles",
      "singularName": "",
      "namespaced": true,
      "kind": "Role",
      "verbs": [
        "create",
        "delete",
        "deletecollection",
        "get",
        "list",
        "patch",
        "update",
        "watch"
      ]
    }
  ]
}[root@k8s-master2 ~]#

对比可见,api各版本支持的资源类型是不一样的,v1和apps/v1和rbac.authorization.k8s.io/v1对比见下:
v1支持的资源类型有:

bindings,componentstatuses,configmap,endpoints,events,limitranges,namespace,nodes,pvc,pv,pods,podtemplates,replicationcontrollers,resourcequotas,secrets,sa,svc

apps/v1支持的资源类型有:

controllerrevisions,daemonsets,replicasets,statefulsets

rbac.authorization.k8s.io/v1支持的资源类型有:

roles,rolebindings,clusterroles,clusterrolebindings

如果使用的api版本和资源类型不匹配会如何呢？见下:

[root@k8s-master1 test]# cat httpd2.yaml
apiVersion: apps/v1beta1
kind: Pod
metadata:
  name: httpd-app
spec:
  replicas: 1
  selector:
    matchLabels:
      app: httpd-app
  template:
      metadata:
        labels:
          app: httpd-app
      spec:
        containers:
        - image: httpd
          name: httpd-app
[root@k8s-master1 test]# kubectl apply -f httpd2.yaml
error: unable to recognize "httpd2.yaml": no matches for kind "Pod" in version "apps/v1beta1"

再测试一个svc

[root@k8s-master1 test]# cat nginx-svc2.yaml
apiVersion: apps/v1
kind: Service
metadata:
  name: nginx-svc
spec:
  ports:
  - port: 80
  selector:
    run: t1
  type: NodePort
[root@k8s-master1 test]# kubectl apply -f nginx-svc2.yaml
error: unable to recognize "nginx-svc2.yaml": no matches for kind "Service" in version "apps/v1"
[root@k8s-master1 test]#

4.
到这里已经解决了开始的困惑,api不同版本对应了不同的资源类型.