62 lines
1.3 KiB
Markdown
62 lines
1.3 KiB
Markdown
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## ReplicaSet 03 - Solution
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1. Create a ReplicaSet with 2 replicas. Make sure the label used for the selector and in the Pods is "type=web"
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```
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cat >> rs.yaml <<EOL
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apiVersion: apps/v1
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kind: ReplicaSet
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metadata:
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name: web
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labels:
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app: somewebapp
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type: web
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spec:
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replicas: 2
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selector:
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matchLabels:
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type: web
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template:
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metadata:
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labels:
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type: web
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spec:
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containers:
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- name: httpd
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image: registry.redhat.io/rhscl/httpd-24-rhel7
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EOL
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kubectl apply -f rs.yaml
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```
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2. Verify a ReplicaSet was created and there are 2 replicas
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```
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kubectl get rs
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# OR a more specific way: kubectl get -f rs.yaml
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```
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3. List the Pods running and save the output somewhere
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```
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kubectl get po > running_pods.txt
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```
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4. Remove the label (type=web) from one of the Pods created by the ReplicaSet
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```
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kubectl label pod <POD_NAME> type-
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```
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5. List the Pods running. Are there more Pods running after removing the label? Why?
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```
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Yes, there is an additional Pod running because once the label, used as a matching selector, was removed, the Pod became independant meaning, it's not controlled by the ReplicaSet anymore and the ReplicaSet was missing replicas based on its definition so, it created a new Pod.
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```
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6. Verify the ReplicaSet indeed created a new Pod
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```
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kubectl describe rs web
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```
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