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‎.gitignore‎

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*.pem
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/aws/
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test
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.github/agents/*

‎labs/k8s/README.md‎

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# Lab09: Minikube
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## Task 1-3
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- [deployment.yaml](./deployment.yaml) (replicas 3)
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- [service.yaml](./service.yaml)
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Usage:
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```sh
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kubectl apply -f labs/k8s/deployment.yaml
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kubectl get deployment python-info-service
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kubectl describe deployment python-info-service
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kubectl get pods -l app=python-info-service
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```
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```sh
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kubectl get deployment python-info-service
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NAME READY UP-TO-DATE AVAILABLE AGE
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python-info-service 3/3 3 3 11m
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kubectl describe deployment python-info-service
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Name: python-info-service
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Namespace: default
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CreationTimestamp: Thu, 26 Mar 2026 21:33:30 +0300
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Labels: app=python-info-service
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Annotations: deployment.kubernetes.io/revision: 1
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Selector: app=python-info-service
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Replicas: 3 desired | 3 updated | 3 total | 3 available | 0 unavailable
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StrategyType: RollingUpdate
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MinReadySeconds: 0
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RollingUpdateStrategy: 0 max unavailable, 1 max surge
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Pod Template:
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Labels: app=python-info-service
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Containers:
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python-info-service:
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Image: projacktor/python-info-service:latest
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Port: 8080/TCP
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Host Port: 0/TCP
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Limits:
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cpu: 200m
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memory: 256Mi
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Requests:
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cpu: 100m
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memory: 128Mi
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Liveness: tcp-socket :8080 delay=15s timeout=2s period=10s #success=1 #failure=3
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Readiness: tcp-socket :8080 delay=5s timeout=2s period=5s #success=1 #failure=3
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Environment: <none>
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Mounts: <none>
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Volumes: <none>
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Node-Selectors: <none>
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Tolerations: <none>
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Conditions:
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Type Status Reason
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---- ------ ------
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Available True MinimumReplicasAvailable
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Progressing True NewReplicaSetAvailable
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OldReplicaSets: <none>
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NewReplicaSet: python-info-service-85d87fc579 (3/3 replicas created)
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Events:
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Type Reason Age From Message
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---- ------ ---- ---- -------
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Normal ScalingReplicaSet 11m deployment-controller Scaled up replica set python-info-service-85d87fc579 from 0 to 3
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kubectl get pods -l app=python-info-service
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NAME READY STATUS RESTARTS AGE
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python-info-service-85d87fc579-rjbx8 1/1 Running 0 11m
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python-info-service-85d87fc579-sxbp5 1/1 Running 0 11m
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python-info-service-85d87fc579-zq7gd 1/1 Running 0 11m
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```
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```sh
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projacktor@projacktorLaptop ~/P/e/DevOps-Core-Course (lab9)> kubectl apply -f labs/k8s/service.yaml
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service/python-info-service created
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projacktor@projacktorLaptop ~/P/e/DevOps-Core-Course (lab9)> kubectl get svc -n default
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
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kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 23h
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python-info-service NodePort 10.104.130.60 <none> 8080:30080/TCP 6s
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projacktor@projacktorLaptop ~/P/e/DevOps-Core-Course (lab9)> kubectl get svc python-info-service -n default
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
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python-info-service NodePort 10.104.130.60 <none> 8080:30080/TCP 16s
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projacktor@projacktorLaptop ~/P/e/DevOps-Core-Course (lab9)> minikube service python-info-service --url
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http://192.168.49.2:30080
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projacktor@projacktorLaptop ~/P/e/DevOps-Core-Course (lab9)> kubectl get services
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
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kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 23h
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python-info-service NodePort 10.104.130.60 <none> 8080:30080/TCP 68s
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projacktor@projacktorLaptop ~/P/e/DevOps-Core-Course (lab9)> kubectl get services python-info-service
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
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python-info-service NodePort 10.104.130.60 <none> 8080:30080/TCP 79s
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projacktor@projacktorLaptop ~/P/e/DevOps-Core-Course (lab9)> kubectl get endpoints
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Warning: v1 Endpoints is deprecated in v1.33+; use discovery.k8s.io/v1 EndpointSlice
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NAME ENDPOINTS AGE
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kubernetes 192.168.49.2:8443 23h
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python-info-service 10.244.0.4:8080,10.244.0.5:8080,10.244.0.6:8080 85s
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```
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## Task 4
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Increase replicas:
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```sh
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kubectl scale deployment/python-info-service --replicas=5
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deployment.apps/python-info-service scaled
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kubectl get pods -w
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NAME READY STATUS RESTARTS AGE
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python-info-service-85d87fc579-c8z74 1/1 Running 0 33s
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python-info-service-85d87fc579-nqxrh 1/1 Running 0 33s
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python-info-service-85d87fc579-rjbx8 1/1 Running 0 16m
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python-info-service-85d87fc579-sxbp5 1/1 Running 0 16m
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python-info-service-85d87fc579-zq7gd 1/1 Running 0 16m
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^C⏎
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kubectl rollout status deployment/python-info-service
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deployment "python-info-service" successfully rolled out
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```
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## Task 5
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### Architecture Overview
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- Cluster: minikube (single-node local Kubernetes)
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- Workload: Deployment/python-info-service
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- Replicas: 3 (scaled to 5 in Task 4)
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- Networking: Service/python-info-service type NodePort (8080 -> 30080)
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- Traffic flow: Client -> NodeIP:30080 -> Service -> Pod:8080
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- Resources per Pod:
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- requests: 100m CPU, 128Mi RAM
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- limits: 200m CPU, 256Mi RAM
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### Manifest Files
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- deployment.yaml
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- replicas: 3
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- RollingUpdate strategy (maxSurge: 1, maxUnavailable: 0)
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- livenessProbe/readinessProbe via TCP 8080
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- resources.requests/limits set for predictable scheduling
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- service.yaml
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- type: NodePort
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- selector app: python-info-service
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- port: 8080, targetPort: 8080, nodePort: 30080
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### Deployment Evidence
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```sh
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kubectl get all
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kubectl get all
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NAME READY STATUS RESTARTS AGE
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pod/python-info-service-85d87fc579-c8z74 1/1 Running 0 5m34s
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pod/python-info-service-85d87fc579-nqxrh 1/1 Running 0 5m34s
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pod/python-info-service-85d87fc579-rjbx8 1/1 Running 0 21m
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pod/python-info-service-85d87fc579-sxbp5 1/1 Running 0 21m
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pod/python-info-service-85d87fc579-zq7gd 1/1 Running 0 21m
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
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service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 23h
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service/python-info-service NodePort 10.104.130.60 <none> 8080:30080/TCP 14m
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NAME READY UP-TO-DATE AVAILABLE AGE
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deployment.apps/python-info-service 5/5 5 5 21m
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NAME DESIRED CURRENT READY AGE
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replicaset.apps/python-info-service-85d87fc579 5 5 5 21m
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```
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```sh
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kubectl get pods,svc -o wide
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NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
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pod/python-info-service-85d87fc579-c8z74 1/1 Running 0 5m56s 10.244.0.8 minikube <none> <none>
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pod/python-info-service-85d87fc579-nqxrh 1/1 Running 0 5m56s 10.244.0.7 minikube <none> <none>
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pod/python-info-service-85d87fc579-rjbx8 1/1 Running 0 22m 10.244.0.4 minikube <none> <none>
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pod/python-info-service-85d87fc579-sxbp5 1/1 Running 0 22m 10.244.0.6 minikube <none> <none>
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pod/python-info-service-85d87fc579-zq7gd 1/1 Running 0 22m 10.244.0.5 minikube <none> <none>
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NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
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service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 23h <none>
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service/python-info-service NodePort 10.104.130.60 <none> 8080:30080/TCP 14m app=python-info-service
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```
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```sh
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kubectl describe deployment python-info-service
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Name: python-info-service
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Namespace: default
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CreationTimestamp: Thu, 26 Mar 2026 21:33:30 +0300
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Labels: app=python-info-service
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Annotations: deployment.kubernetes.io/revision: 1
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Selector: app=python-info-service
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Replicas: 5 desired | 5 updated | 5 total | 5 available | 0 unavailable
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StrategyType: RollingUpdate
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MinReadySeconds: 0
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RollingUpdateStrategy: 0 max unavailable, 1 max surge
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Pod Template:
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Labels: app=python-info-service
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Containers:
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python-info-service:
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Image: projacktor/python-info-service:latest
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Port: 8080/TCP
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Host Port: 0/TCP
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Limits:
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cpu: 200m
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memory: 256Mi
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Requests:
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cpu: 100m
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memory: 128Mi
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Liveness: tcp-socket :8080 delay=15s timeout=2s period=10s #success=1 #failure=3
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Readiness: tcp-socket :8080 delay=5s timeout=2s period=5s #success=1 #failure=3
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Environment: <none>
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Mounts: <none>
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Volumes: <none>
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Node-Selectors: <none>
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Tolerations: <none>
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Conditions:
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Type Status Reason
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---- ------ ------
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Progressing True NewReplicaSetAvailable
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Available True MinimumReplicasAvailable
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OldReplicaSets: <none>
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NewReplicaSet: python-info-service-85d87fc579 (5/5 replicas created)
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Events:
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Type Reason Age From Message
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---- ------ ---- ---- -------
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Normal ScalingReplicaSet 22m deployment-controller Scaled up replica set python-info-service-85d87fc579 from 0 to 3
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Normal ScalingReplicaSet 6m26s deployment-controller Scaled up replica set python-info-service-85d87fc579 from 3 to 5
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```
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#### App accessibility check
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```sh
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curl http://192.168.49.2:30080/
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{"service":{"name":"devops-info-service","version":"1.0.0","description":"DevOps course info service","framework":"FastAPI"},"system":{"hostname":"python-info-service-85d87fc579-nqxrh","platform":"Linux","platform_version":"#37~24.04.1-Ubuntu SMP PREEMPT_DYNAMIC Thu Nov 20 10:25:38 UTC 2","architecture":"x86_64","cpu_count":16,"python_version":"3.12.13"},"runtime":{"uptime_seconds":428,"uptime_human":"0 hours, 7 minutes","current_time":"2026-03-26T18:56:57.746777","timezone":"UTC"},"request":{"client_ip":"10.244.0.1","user_agent":"curl/8.5.0","method":"GET","path":"/"},"endpoints":[{"path":"/","method":"GET","description":"Service information"},{"path":"/health","method":"GET","description":"Health check"}]}⏎
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```
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### Operations Performed
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#### Deploy
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- ```kubectl apply -f labs/k8s/deployment.yaml```
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- ```kubectl apply -f labs/k8s/service.yaml```
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#### Scale
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- ```kubectl scale deployment/python-info-service --replicas=5```
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- ```kubectl rollout status deployment/python-info-service```
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#### Rolling update
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- Performed by changing runtime config:
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- ```kubectl set env deployment/python-info-service RELEASE=lab09-update```
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- Verified:
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- ```kubectl rollout status deployment/python-info-service```
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- ```kubectl rollout history deployment/python-info-service```
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#### Rollback
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- ```kubectl rollout undo deployment/python-info-service```
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- Verified:
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- ```kubectl rollout status deployment/python-info-service```
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- ```kubectl rollout history deployment/python-info-service```
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### Production Considerations
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- Health checks:
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- readiness probe prevents routing traffic to not-ready Pods
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- liveness probe restarts hung container
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- Resource limits:
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- protect node from noisy-neighbor effect
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- guarantee minimum CPU/memory via requests
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- Production improvements:
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- use fixed image tags (not latest)
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- add startupProbe for slow starts
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- add HPA + metrics-server
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- central logging/monitoring (Prometheus + Grafana, Loki/ELK)
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### Challenges & Solutions
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- Issue: Service not found in minikube
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- Cause: wrong kubectl context/namespace
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- Fix: kubectl config use-context minikube, then re-apply manifests
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- Issue: Deployment initially showed 0/3 available
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- Cause: probes and startup delay
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- Fix: waited for readiness and checked with kubectl rollout status
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- Learning:
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- Kubernetes is declarative; actual state converges asynchronously
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- Labels/selectors are critical for Service-to-Pod routing

‎labs/k8s/deployment.yaml‎

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apiVersion: apps/v1
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kind: Deployment
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metadata:
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name: python-info-service
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labels:
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app: python-info-service
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spec:
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replicas: 3
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strategy:
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type: RollingUpdate
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rollingUpdate:
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maxSurge: 1
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maxUnavailable: 0
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selector:
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matchLabels:
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app: python-info-service
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template:
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metadata:
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labels:
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app: python-info-service
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spec:
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containers:
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- name: python-info-service
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image: projacktor/python-info-service:latest
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ports:
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- containerPort: 8080
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resources:
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requests:
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cpu: "100m"
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memory: "128Mi"
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limits:
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cpu: "200m"
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memory: "256Mi"
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livenessProbe:
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tcpSocket:
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port: 8080
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initialDelaySeconds: 15
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periodSeconds: 10
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timeoutSeconds: 2
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failureThreshold: 3
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readinessProbe:
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tcpSocket:
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port: 8080
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initialDelaySeconds: 5
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periodSeconds: 5
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timeoutSeconds: 2
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failureThreshold: 3

‎labs/k8s/service.yaml‎

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apiVersion: v1
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kind: Service
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metadata:
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name: python-info-service
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spec:
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type: NodePort
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selector:
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app: python-info-service
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ports:
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- protocol: TCP
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port: 8080
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targetPort: 8080
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nodePort: 30080

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