YAML（/ˈjæməl/，尾音类似camel骆驼）是一个可读性高，用来表达数据序列化的格式。YAML参考了其他多种语言，包括：C语言、Python、Perl，并从XML、电子邮件的数据格式（RFC 2822）中获得灵感。Clark Evans在2001年首次发表了这种语言[1]，另外Ingy döt Net与Oren Ben-Kiki也是这语言的共同设计者[2]。当前已经有数种编程语言或脚本语言支持（或者说解析）这种语言。YAML是"YAML Ain't a Markup Language"（YAML不是一种标记语言）的递归缩写。在开发的这种语言时，YAML 的意思其实是："Yet Another Markup Language"（仍是一种标记语言）[3]，但为了强调这种语言以数据做为中心，而不是以标记语言为重点，而用反向缩略语重命名。

[root@kube ~]# kubectl get pod nginx-app-7756966bc9-qrksb -o yaml　　　　//这是一个通过 kubectl run 方式运行的 pod ，那么我们可以手动定义一个 和这个类似的 yaml 配置文件进行加载然后生成pod
apiVersion: v1
kind: Pod
metadata:creationTimestamp: "2019-07-16T06:39:02Z"generateName: nginx-app-7756966bc9-labels:pod-template-hash: 7756966bc9run: nginx-appname: nginx-app-7756966bc9-qrksbnamespace: defaultownerReferences:- apiVersion: apps/v1blockOwnerDeletion: truecontroller: truekind: ReplicaSetname: nginx-app-7756966bc9uid: 51997507-0ad5-4f71-86db-3ad6eff70171resourceVersion: "603662"selfLink: /api/v1/namespaces/default/pods/nginx-app-7756966bc9-qrksbuid: 7035cfbd-a8f3-45a9-933c-4ce1cef45183
spec:containers:- image: nginx:alpineimagePullPolicy: IfNotPresentname: nginx-appports:- containerPort: 80protocol: TCPresources: {}terminationMessagePath: /dev/termination-logterminationMessagePolicy: FilevolumeMounts:- mountPath: /var/run/secrets/kubernetes.io/serviceaccountname: default-token-bsthb readOnly: truednsPolicy: ClusterFirstenableServiceLinks: truenodeName: kube.node1priority: 0restartPolicy: AlwaysschedulerName: default-schedulersecurityContext: {}serviceAccount: defaultserviceAccountName: defaultterminationGracePeriodSeconds: 30tolerations:- effect: NoExecutekey: node.kubernetes.io/not-readyoperator: ExiststolerationSeconds: 300- effect: NoExecutekey: node.kubernetes.io/unreachableoperator: ExiststolerationSeconds: 300volumes:- name: default-token-bsthbsecret:defaultMode: 420secretName: default-token-bsthb
status:conditions:- lastProbeTime: nulllastTransitionTime: "2019-07-16T06:39:02Z"status: "True"type: Initialized- lastProbeTime: nulllastTransitionTime: "2019-07-16T06:39:36Z"status: "True"type: Ready- lastProbeTime: nulllastTransitionTime: "2019-07-16T06:39:36Z"status: "True"type: ContainersReady- lastProbeTime: nulllastTransitionTime: "2019-07-16T06:39:02Z"status: "True"type: PodScheduledcontainerStatuses:- containerID: docker://6f50a8038d1f9b484c3af46fa21ef0bdce963b95c4f7f5980302bc70ca46eea6image: nginx:alpineimageID: docker-pullable://nginx@sha256:17bd1698318e9c0f9ba2c5ed49f53d690684dab7fe3e8019b855c352528d57belastState: {}name: nginx-appready: truerestartCount: 0state:running:startedAt: "2019-07-16T06:39:36Z"hostIP: 10.2.61.22phase: RunningpodIP: 10.244.2.7qosClass: BestEffortstartTime: "2019-07-16T06:39:02Z"
[root@kube ~]#

#maps 是key|value 的组合，list 是key[args,args ，多个项的组合]用破折号（-）开头apiVersion: v1  //maps
kind: Pod　　　　　//maps
metadata:　　　　　　name: rss-site　　//mapslabels:app: web　　　　/maps
spec:            //mapscontainers:    //list name - name: front-end　　//list参数子项是mapsimage: nginx　　　　//list 参数子项是mapsports:             - containerPort: 80   //list 参数子项maps- name: rss-readerimage: nickchase/rss-php-nginx:v1ports:- containerPort: 88

root@kube test]# cat pod-demo.yaml
apiVersion: v1
kind: Pod
metadata:name: pod-testnamespace: defaultlabels:app: myapptier: frontend
spec:containers:- name: mytestimage: nginx:latest[root@kube test]#

[root@kube test]# kubectl create -f pod-demo.yaml
pod/pod-test created
[root@kube test]# kubectl get pods
NAME                         READY   STATUS              RESTARTS   AGE
busy1-78c9f4b47-pm2qx        0/1     CrashLoopBackOff    22         100m
busy2-7f9dbf96d6-2d778       1/1     Running             0          2d23h
busy3-9877c76bf-ts5rl        1/1     Running             0          2d23h
nginx-7bb7cd8db5-6sgvp       1/1     Running             0          3d
nginx-app-54c844949f-6zlmr   0/1     ContainerCreating   0          41h
nginx-app-54c844949f-n82d6   1/1     Running             0          2d
nginx-app-54c844949f-xmkb8   1/1     Running             0          2d
nginx-app-7756966bc9-qrksb   1/1     Running             0          2d2h
pod-test                     0/1     ContainerCreating   0          1s
[root@kube test]#

[root@kube test]# kubectl describe pod pod-test
Name:         pod-test
Namespace:    default
Priority:     0
Node:         kube.node1/10.2.61.22
Start Time:   Thu, 18 Jul 2019 16:44:23 +0800
Labels:       app=myapptier=frontend
Annotations:  <none>
Status:       Running
IP:           10.244.2.12
Containers:mytest:Container ID:   docker://4e40fc5b6cae440881cea707b79c2d17692c47d75df69a571fa0e7d57dff5e3aImage:          nginx:latestImage ID:       docker-pullable://nginx@sha256:b4b9b3eee194703fc2fa8afa5b7510c77ae70cfba567af1376a573a967c03dbbPort:           <none>Host Port:      <none>State:          RunningStarted:      Thu, 18 Jul 2019 16:44:46 +0800Ready:          TrueRestart Count:  0Environment:    <none>Mounts:/var/run/secrets/kubernetes.io/serviceaccount from default-token-bsthb (ro)
Conditions:Type              StatusInitialized       True Ready             True ContainersReady   True PodScheduled      True
Volumes:default-token-bsthb:Type:        Secret (a volume populated by a Secret)SecretName:  default-token-bsthbOptional:    false
QoS Class:       BestEffort
Node-Selectors:  <none>
Tolerations:     node.kubernetes.io/not-ready:NoExecute for 300snode.kubernetes.io/unreachable:NoExecute for 300s
Events:Type    Reason     Age   From                 Message----    ------     ----  ----                 -------Normal  Scheduled  62s   default-scheduler    Successfully assigned default/pod-test to kube.node1Normal  Pulling    61s   kubelet, kube.node1  Pulling image "nginx:latest"Normal  Pulled     40s   kubelet, kube.node1  Successfully pulled image "nginx:latest"Normal  Created    40s   kubelet, kube.node1  Created container mytestNormal  Started    39s   kubelet, kube.node1  Started container mytest
[root@kube test]#

[root@kube ~]# 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/v1
coordination.k8s.io/v1beta1
events.k8s.io/v1beta1
extensions/v1beta1
networking.k8s.io/v1
networking.k8s.io/v1beta1
node.k8s.io/v1beta1
policy/v1beta1
rbac.authorization.k8s.io/v1
rbac.authorization.k8s.io/v1beta1
scheduling.k8s.io/v1
scheduling.k8s.io/v1beta1
storage.k8s.io/v1
storage.k8s.io/v1beta1
v1
[root@kube ~]# kubectl explain pods
KIND:     Pod
VERSION:  v1DESCRIPTION:Pod is a collection of containers that can run on a host. This resource iscreated by clients and scheduled onto hosts.FIELDS:apiVersion <string>APIVersion defines the versioned schema of this representation of anobject. Servers should convert recognized schemas to the latest internalvalue, and may reject unrecognized values. More info:https://git.k8s.io/community/contributors/devel/api-conventions.md#resourceskind <string>Kind is a string value representing the REST resource this objectrepresents. Servers may infer this from the endpoint the client submitsrequests to. Cannot be updated. In CamelCase. More info:https://git.k8s.io/community/contributors/devel/api-conventions.md#types-kindsmetadata    <Object>Standard object's metadata. More info:https://git.k8s.io/community/contributors/devel/api-conventions.md#metadataspec    <Object>Specification of the desired behavior of the pod. More info:https://git.k8s.io/community/contributors/devel/api-conventions.md#spec-and-statusstatus  <Object>Most recently observed status of the pod. This data may not be up to date.Populated by the system. Read-only. More info:https://git.k8s.io/community/contributors/devel/api-conventions.md#spec-and-status[root@kube ~]#