Kubernetes resource list definition
Kubernetes is a ReSTful API
GET,PUT,DELETE,POST
kubectl run ,get,edit
Resources, objects
workload: Pod, replicate, Statefulset, Daemonset, job, Cronjob, etc
Service discovery and load balancing: service, Ingress
Configuration and storage: Volume, CSI
ConfigMap,Secret
DownwardAPI
Cluster level resources
Namespace, Node, Role, ClusterRole, rolebinding (Role binding), clusterrolebinding (cluster Role binding)
Metadata resources
HPA, podtemplate, limitrange
Three levels of api Group: apiversion
Beta version
beta test version public test (unstable)
v1 stable version
In general, you can use the configuration list to create
Let's take a look at the Pod we created earlier
[root@master ~]# kubectl get pods NAME READY STATUS RESTARTS AGE client 1/1 Running 0 11h myapp-848b5b879b-4xpl7 1/1 Running 0 10h myapp-848b5b879b-7gtn4 1/1 Running 0 10h myapp-848b5b879b-xtcdd 1/1 Running 0 10h nginx-deploy-5b595999-fsxlp 1/1 Running 0 11h
[root@master ~]# kubectl get pod myapp-848b5b879b-4xpl7
NAME READY STATUS RESTARTS AGE
myapp-848b5b879b-4xpl7 1/1 Running 0 10h
[root@master ~]# kubectl get pod myapp-848b5b879b-4xpl7 -o yaml
apiVersion: v1
kind: Pod #category
metadata: #Nested field
creationTimestamp: 2018-09-04T17:07:58Z
generateName: myapp-848b5b879b-
labels:
pod-template-hash: "4046164356"
run: myapp
name: myapp-848b5b879b-4xpl7
namespace: default
ownerReferences:
- apiVersion: apps/v1
blockOwnerDeletion: true
controller: true
kind: ReplicaSet
name: myapp-848b5b879b
uid: 41924f50-b061-11e8-a432-000c29f33006
resourceVersion: "10899"
selfLink: /api/v1/namespaces/default/pods/myapp-848b5b879b-4xpl7
uid: 1259f6af-b065-11e8-a432-000c29f33006
spec: #Very important fields, resource specifications
containers:
- image: ikubernetes/myapp:v1
imagePullPolicy: IfNotPresent
name: myapp
resources: {}
terminationMessagePath: /dev/termination-log
terminationMessagePolicy: File
volumeMounts:
- mountPath: /var/run/secrets/kubernetes.io/serviceaccount
name: default-token-8zzcr
readOnly: true
dnsPolicy: ClusterFirst
nodeName: node1
priority: 0
restartPolicy: Always
schedulerName: default-scheduler
securityContext: {}
serviceAccount: default
serviceAccountName: default
terminationGracePeriodSeconds: 30
tolerations:
- effect: NoExecute
key: node.kubernetes.io/not-ready
operator: Exists
tolerationSeconds: 300
- effect: NoExecute
key: node.kubernetes.io/unreachable
operator: Exists
tolerationSeconds: 300
volumes:
- name: default-token-8zzcr
secret:
defaultMode: 420
secretName: default-token-8zzcr
status:#Read only fields
conditions:
- lastProbeTime: null
lastTransitionTime: 2018-09-04T17:07:57Z
status: "True"
type: Initialized
- lastProbeTime: null
lastTransitionTime: 2018-09-04T17:07:58Z
status: "True"
type: Ready
- lastProbeTime: null
lastTransitionTime: null
status: "True"
type: ContainersReady
- lastProbeTime: null
lastTransitionTime: 2018-09-04T17:07:58Z
status: "True"
type: PodScheduled
containerStatuses:
- containerID: docker://8e757445c75729e865de6462d7dc4e849909776f8a34657ceab3f11baf569c0d
image: ikubernetes/myapp:v1
imageID: docker-pullable://ikubernetes/myapp@sha256:9c3dc30b5219788b2b8a4b065f548b922a34479577befb54b03330999d30d513
lastState: {}
name: myapp
ready: true
restartCount: 0
state:
running:
startedAt: 2018-09-04T17:07:58Z
hostIP: 192.168.68.20
phase: Running
podIP: 10.244.1.8
qosClass: BestEffort
startTime: 2018-09-04T17:07:57Z
How to create a resource:
Apserver only receives resource definitions in JSON format;
The configuration list provided in yaml format can be automatically converted into json format by apiserver, and then submitted
Format list of most resources:
apiVersion which group and version to create belongs to, pay attention to the case of kubectl API versions
kind: resource category
Metadata: metadata
name
namespace
labels
annotations
PATH of each resource reference
/api/GROUP/VERSION/namespaces/NAMESPACE/TYPE/NAME
Replacement of uppercase
spec: desired state
status: current state. This field is created by kubernets to make the current state close to the desired state
See how the pod resource defines kubectl explain pods
Create the first yaml file: two containers created on top of a pod
[root@master manifests]# cat pod-demo.yaml
apiVersion: v1
kind: Pod
metadata:
name: pod-demo
namespace: default
labels:
app: myapp
tier: frontend
spec:
containers:
- name: myapp
image: ikubernetes/myapp:v1
- name: busybox
image: busybox:latest
command:
- "/bin/sh"
- "-c"
- "sleep 3600"Start creation: kubectl create -f pod-demo.yaml
View your own creation: kubectl get pod
[root@master manifests]# kubectl get pod NAME READY STATUS RESTARTS AGE client 1/1 Running 0 13h myapp-848b5b879b-4xpl7 1/1 Running 0 12h myapp-848b5b879b-7gtn4 1/1 Running 0 12h myapp-848b5b879b-xtcdd 1/1 Running 0 12h nginx-deploy-5b595999-fsxlp 1/1 Running 0 13h pod-demo 2/2 Running 0 1m
Delete your own creation: kubectl delete - f pod demo.yaml
Get the details of the pod demo you just created:
kubectl describe pods pod-demo
[root@master manifests]# kubectl describe pods pod-demo
Name: pod-demo #Resource name
Namespace: default #Namespace
Priority: 0
PriorityClassName: <none>
Node: node2/192.168.68.30 #Which node is running on
Start Time: Wed, 05 Sep 2018 13:33:26 +0800
Labels: app=myapp #Label
tier=frontend
Annotations: <none>
Status: Running
IP: 10.244.2.10
Containers:
myapp: #First container
Container ID: docker://aa6be83a949e31c1935fe607e9238fd3bc64b51bfa851350ea502c31371d07e4
Image: ikubernetes/myapp:v1
Image ID: docker-pullable://ikubernetes/myapp@sha256:9c3dc30b5219788b2b8a4b065f548b922a34479577befb54b03330999d30d513
Port: <none>
Host Port: <none>
State: Running
Started: Wed, 05 Sep 2018 13:33:26 +0800
Ready: True
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from default-token-8zzcr (ro)
busybox: #Second container
Container ID: docker://942c9ee53afcc890cbd1471877c5ecca238a8eb9de40fd5399bc3bbfd9e42d28
Image: busybox:latest
Image ID: docker-pullable://busybox@sha256:cb63aa0641a885f54de20f61d152187419e8f6b159ed11a251a09d115fdff9bd
Port: <none>
Host Port: <none>
Command:
/bin/sh
-c
sleep 3600
State: Running
Started: Wed, 05 Sep 2018 13:33:31 +0800
Ready: True
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from default-token-8zzcr (ro)
Conditions:
Type Status
Initialized True
Ready True
ContainersReady True
PodScheduled True
Volumes:
default-token-8zzcr:
Type: Secret (a volume populated by a Secret)
SecretName: default-token-8zzcr
Optional: false
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute for 300s
node.kubernetes.io/unreachable:NoExecute for 300s
Events: #Created details
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled 3m default-scheduler Successfully assigned default/pod-demo to node2
Normal Pulled 3m kubelet, node2 Container image "ikubernetes/myapp:v1" already present on machine
Normal Created 3m kubelet, node2 Created container
Normal Started 3m kubelet, node2 Started container
Normal Pulling 3m kubelet, node2 pulling image "busybox:latest"
Normal Pulled 3m kubelet, node2 Successfully pulled image "busybox:latest"
Normal Created 3m kubelet, node2 Created container
Normal Started 3m kubelet, node2 Started container
See myapp Access log for: [root@master manifests]# curl 10.244.2.10 #ip is generated above Hello MyApp | Version: v1 | <a href="hostname.html">Pod Name</a> [root@master manifests]# kubectl logs pod-demo myapp 10.244.0.0 - - [05/Sep/2018:05:45:35 +0000] "GET / HTTP/1.1" 200 65 "-" "curl/7.29.0" "-" 10.244.0.0 - - [05/Sep/2018:05:45:44 +0000] "GET / HTTP/1.1" 200 65 "-" "curl/7.29.0" "-" pod Monitoring created: kubectl get pods -w //To delete a pod demo project: [root@master manifests]# kubectl delete pods pod-demo pod "pod-demo" deleted [root@master manifests]# kubectl get pod NAME READY STATUS RESTARTS AGE client 1/1 Running 0 13h myapp-848b5b879b-4xpl7 1/1 Running 0 12h myapp-848b5b879b-7gtn4 1/1 Running 0 12h myapp-848b5b879b-xtcdd 1/1 Running 0 12h nginx-deploy-5b595999-fsxlp 1/1 Running 0 13h
adopt kubectl api-versions You can check it. api Version [root@master ~]# 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 #Beta version authorization.k8s.io/v1 authorization.k8s.io/v1beta1 autoscaling/v1 autoscaling/v2beta1 batch/v1 batch/v1beta1 certificates.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