Kubernetes: архитектура и основные концепции

1apiVersion: v1
2kind: Pod
3metadata:
4  name: myapp
5  labels:
6    app: myapp
7spec:
8  containers:
9  - name: web
10    image: nginx:1.25
11    ports:
12    - containerPort: 80
13    resources:
14      requests:
15        memory: "64Mi"
16        cpu: "250m"
17      limits:
18        memory: "128Mi"
19        cpu: "500m"
20  - name: sidecar
21    image: busybox
22    command: ['sh', '-c', 'while true; do echo "sidecar"; sleep 60; done']

1apiVersion: apps/v1
2kind: Deployment
3metadata:
4  name: myapp
5spec:
6  replicas: 3
7  selector:
8    matchLabels:
9      app: myapp
10  template:
11    metadata:
12      labels:
13        app: myapp
14    spec:
15      containers:
16      - name: web
17        image: myapp:1.0
18        ports:
19        - containerPort: 8080
20  strategy:
21    type: RollingUpdate
22    rollingUpdate:
23      maxSurge: 1
24      maxUnavailable: 0

1# ClusterIP (внутренний доступ)
2apiVersion: v1
3kind: Service
4metadata:
5  name: myapp-service
6spec:
7  type: ClusterIP
8  selector:
9    app: myapp
10  ports:
11  - port: 80
12    targetPort: 8080
13
14---
15# NodePort (доступ через ноду)
16apiVersion: v1
17kind: Service
18metadata:
19  name: myapp-nodeport
20spec:
21  type: NodePort
22  selector:
23    app: myapp
24  ports:
25  - port: 80
26    targetPort: 8080
27    nodePort: 30080
28
29---
30# LoadBalancer (внешний балансировщик)
31apiVersion: v1
32kind: Service
33metadata:
34  name: myapp-lb
35spec:
36  type: LoadBalancer
37  selector:
38    app: myapp
39  ports:
40  - port: 80
41    targetPort: 8080

1apiVersion: networking.k8s.io/v1
2kind: Ingress
3metadata:
4  name: myapp-ingress
5  annotations:
6    nginx.ingress.kubernetes.io/rewrite-target: /
7spec:
8  rules:
9  - host: myapp.example.com
10    http:
11      paths:
12      - path: /
13        pathType: Prefix
14        backend:
15          service:
16            name: myapp-service
17            port:
18              number: 80

1apiVersion: v1
2kind: ConfigMap
3metadata:
4  name: myapp-config
5data:
6  DATABASE_HOST: "db.example.com"
7  LOG_LEVEL: "info"
8
9---
10apiVersion: v1
11kind: Secret
12metadata:
13  name: myapp-secret
14type: Opaque
15data:
16  DB_PASSWORD: cGFzc3dvcmQxMjM=

1apiVersion: autoscaling/v2
2kind: HorizontalPodAutoscaler
3metadata:
4  name: myapp-hpa
5spec:
6  scaleTargetRef:
7    apiVersion: apps/v1
8    kind: Deployment
9    name: myapp
10  minReplicas: 2
11  maxReplicas: 10
12  metrics:
13  - type: Resource
14    resource:
15      name: cpu
16      target:
17        type: Utilization
18        averageUtilization: 70

1# Просмотр подов
2kubectl get pods -o wide
3
4# Логи
5kubectl logs -f myapp-pod
6
7# Exec
8kubectl exec -it myapp-pod -- sh
9
10# Порт-форвардинг
11kubectl port-forward svc/myapp-service 8080:80
12
13# Масштабирование
14kubectl scale deployment myapp --replicas=5