K8s Pod
On the right hand are reference infomations for create kubernetes resources. resources manifast / official document.
Create Pod using yaml file
pod.yaml
apiVersion: v1 # api 文档版本
kind: Pod #资源对象类型，其他的：Deployment、StatefulSet
metadata: #Pod的相关元数据，用于描述pod的数据
name: my-nginx #pod的名称
labels: #定义pod标签
type: app
version: 1.0.x #自定义
namespace: 'default' #配置命名空间，默认的是default
spec: #期望pod 按照这里的描述进行创建
containers:
- name: nginx
image: nginx:1.26.0
imagePullPolicy: IfNotPresent #指定镜像拉取策略，如果本地没有就拉取远程
command:
- nginx
- -g
- 'daemon off;' #意为：nginx -g 'daemon off;'
workingDir: /usr/share/nginx/html #指定容器启动后的工作目录
ports:
- name: http #端口名称
containerPort: 80 #描述容器内要暴露的端口
protocol: TCP #描述该端口是基于那种协议通信
env: # 环境变量
- name: JVM-OPTS #环境名称
value: '-Xms128m -Xmx128m' #环境变量的值
resources:
requests:
cpu: 100m # cpu一个核心为1000m，这里的100m 为最少0.1个核心
memory: "128Mi" #最少128兆
limits:
cpu: 200m # cpu一个核心为1000m，这里的200m 为最多0.2个核心
memory: "256Mi" #最多256兆
#command: ["stress"]
#args: ["--vm", "1", "--vm-bytes", "150M", "--vm-hang", "1"]
restartPolicy: OnFailure #重启策略：只用失败的情况才会重启
check the pod
Operation_result
[root@k8s-master pods]# kubectl get pod
NAME READY STATUS RESTARTS AGE
memory-demo-3 1/1 Running 0 4m50s
my-nginx 1/1 Running 0 3m31s
[root@k8s-master pods]# kubectl get pod -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
memory-demo-3 1/1 Running 0 4m55s 192.168.36.72 k8s-node1 <none> <none>
my-nginx 1/1 Running 0 3m36s 192.168.36.73 k8s-node1 <none> <none>
[root@k8s-master pods]# kubectl describe pod my-nginx
Name: my-nginx
Namespace: default
Priority: 0
Node: k8s-node1/10.0.0.101
Start Time: Wed, 24 Apr 2024 06:49:02 -0400
Labels: type=app
version=1.0.x
Annotations: cni.projectcalico.org/containerID: bb27fe44a58187928bced7bb6a76234c1717ea8a000d35e8948796a7970b548a
cni.projectcalico.org/podIP: 192.168.36.73/32
cni.projectcalico.org/podIPs: 192.168.36.73/32
Status: Running
IP: 192.168.36.73
IPs:
IP: 192.168.36.73
Containers:
nginx:
Container ID: docker://71f60f7711b116cf0a6dfa8041381f83c51d40b35ef15f4c0c8756e12ce45c33
Image: nginx:1.26.0
Image ID: docker-pullable://nginx@sha256:3f28ecedbd787b3ff0a6d56cd4a1b13901acda532c717e3b7351fcc786973d79
Port: 80/TCP
Host Port: 0/TCP
Command:
nginx
-g
daemon off;
State: Running
Started: Wed, 24 Apr 2024 06:49:03 -0400
Ready: True
Restart Count: 0
Limits:
cpu: 200m
memory: 256Mi
Requests:
cpu: 100m
memory: 128Mi
Environment:
JVM-OPTS: -Xms128m -Xmx128m
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-mkwwb (ro)
Conditions:
Type Status
Initialized True
Ready True
ContainersReady True
PodScheduled True
Volumes:
kube-api-access-mkwwb:
Type: Projected (a volume that contains injected data from multiple sources)
TokenExpirationSeconds: 3607
ConfigMapName: kube-root-ca.crt
ConfigMapOptional: <nil>
DownwardAPI: true
QoS Class: Burstable
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute op=Exists for 300s
node.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled 3m55s default-scheduler Successfully assigned default/my-nginx to k8s-node1
Normal Pulled 3m55s kubelet Container image "nginx:1.26.0" already present on machine
Normal Created 3m55s kubelet Created container nginx
Normal Started 3m55s kubelet Started container nginx
[root@k8s-master pods]#