Recreate update strategy in Kubernetes - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the update strategy as Recreate in a Deployment manifest.

Kubernetes

strategy:
  type: [1]

Drag options to blanks, or click blank then click option'

ARecreate

BOnDelete

CRollingUpdate

DBlueGreen

Attempts:

3 left

💡 Hint

Common Mistakes

Using RollingUpdate instead of Recreate causes pods to update gradually.

Using OnDelete requires manual pod deletion, not automatic updates.

The Recreate update strategy stops all old pods before creating new ones, ensuring no overlap.

2fill in blank

medium

Complete the Deployment YAML snippet to set the update strategy to Recreate.

Kubernetes

apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-app
spec:
  replicas: 3
  [1]:
    type: Recreate

Drag options to blanks, or click blank then click option'

Aselector

Btemplate

Cstrategy

DreplicaSet

Attempts:

3 left

💡 Hint

Common Mistakes

Placing 'type: Recreate' under 'selector' or 'template' causes errors.

Missing the 'strategy' field means default RollingUpdate is used.

The strategy field defines how pods are updated in a Deployment.

3fill in blank

hard

Fix the error in the Deployment YAML to use the Recreate update strategy correctly.

Kubernetes

spec:
  replicas: 2
  strategy:
    [1]: Recreate

Drag options to blanks, or click blank then click option'

AstrategyType

Bmode

CupdateStrategy

Dtype

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'mode' or 'updateStrategy' instead of 'type' causes the strategy to be ignored.

Misspelling 'type' leads to default RollingUpdate.

The correct key to specify the update strategy type is type.

4fill in blank

hard

Fill both blanks to complete the Deployment spec that uses Recreate strategy and sets replicas to 4.

Kubernetes

spec:
  replicas: [1]
  strategy:
    type: [2]

Drag options to blanks, or click blank then click option'

A4

BRollingUpdate

CRecreate

D3

Attempts:

3 left

💡 Hint

Common Mistakes

Using RollingUpdate instead of Recreate changes update behavior.

Setting replicas to 3 instead of 4 does not match the requirement.

Setting replicas to 4 and strategy type to Recreate ensures all pods are replaced at once with 4 replicas.

5fill in blank

hard

Fill all three blanks to create a Deployment spec with 2 replicas, Recreate update strategy, and a matchLabels selector.

Kubernetes

spec:
  replicas: [1]
  selector:
    matchLabels:
      app: [2]
  strategy:
    type: [3]

Drag options to blanks, or click blank then click option'

Amy-app

B2

CRecreate

DRollingUpdate

Attempts:

3 left

💡 Hint

Common Mistakes

Using RollingUpdate instead of Recreate changes update behavior.

Mixing up replicas and label values.

This Deployment has 2 replicas, selects pods with label 'app: my-app', and uses the Recreate update strategy.

Practice

1. What does the Recreate update strategy do in Kubernetes?

easy

A. Deletes old pods before creating new ones, causing downtime

B. Creates new pods first, then deletes old pods to avoid downtime

C. Updates pods one by one without deleting any

D. Scales pods up and down simultaneously during update

Solution

1. Step 1: Understand the Recreate strategy behavior

   The Recreate strategy deletes all old pods before starting new pods, which causes downtime.

2. Step 2: Compare with other strategies

   Other strategies like RollingUpdate create new pods before deleting old ones to avoid downtime, unlike Recreate.

3. Final Answer:

   Deletes old pods before creating new ones, causing downtime -> Option A

4. Quick Check:

   Recreate = delete old pods first [OK]

Hint: Recreate means delete old pods first, then create new [OK]

Common Mistakes:

• Confusing Recreate with RollingUpdate
• Thinking Recreate avoids downtime
• Assuming pods update one by one

2. Which YAML snippet correctly sets the update strategy to Recreate in a Deployment?

easy

A. strategy:\n type: RollingUpdate

B. strategy:\n type: Recreate

C. updateStrategy:\n type: Recreate

D. deploymentStrategy:\n type: Recreate

Solution

1. Step 1: Identify correct field name for update strategy

   The correct field under Deployment spec is strategy with a nested type.

2. Step 2: Check correct value for Recreate

   The value must be exactly Recreate to set that strategy.

3. Final Answer:

   strategy:\n type: Recreate -> Option B

4. Quick Check:

   strategy.type = Recreate [OK]

Hint: Use 'strategy.type: Recreate' exactly in Deployment spec [OK]

Common Mistakes:

• Using wrong field names like updateStrategy or deploymentStrategy
• Setting type to RollingUpdate instead of Recreate
• Incorrect indentation or YAML syntax

3. Given this Deployment with strategy.type: Recreate, what happens when you update the container image?

medium

A. Pods update one by one without downtime

B. New pods start first, then old pods terminate, no downtime

C. All old pods are terminated before new pods start, causing downtime

D. Pods scale up and down simultaneously

Solution

1. Step 1: Understand Recreate update behavior on image change

   When the image changes, Recreate deletes all old pods before creating new pods.

2. Step 2: Recognize downtime impact

   Because old pods are deleted first, there is downtime until new pods are ready.

3. Final Answer:

   All old pods are terminated before new pods start, causing downtime -> Option C

4. Quick Check:

   Recreate update = downtime during pod replacement [OK]

Hint: Recreate deletes old pods first, causing downtime on update [OK]

Common Mistakes:

• Assuming pods update without downtime
• Confusing with RollingUpdate behavior
• Thinking pods update one by one

4. You set strategy.type: Recreate but notice pods are not deleted before new ones start. What is the likely issue?

medium

A. The Deployment has maxUnavailable set to 0, causing RollingUpdate behavior

B. The Deployment is using StatefulSet instead of Deployment

C. The pods have readinessProbe misconfigured

D. The strategy type is misspelled or incorrectly set

Solution

1. Step 1: Check strategy type correctness

   If pods are not deleted first, the strategy type may be misspelled or set incorrectly, so Kubernetes defaults to RollingUpdate.

2. Step 2: Rule out other causes

   maxUnavailable affects RollingUpdate, readinessProbe affects pod readiness, and StatefulSet is a different resource type.

3. Final Answer:

   The strategy type is misspelled or incorrectly set -> Option D

4. Quick Check:

   Misspelled strategy.type causes default RollingUpdate [OK]

Hint: Check exact spelling of strategy.type: Recreate [OK]

Common Mistakes:

• Assuming maxUnavailable affects Recreate
• Ignoring YAML syntax errors
• Confusing Deployment with StatefulSet

5. You have an app that cannot run multiple versions simultaneously. How do you configure the Deployment update strategy to avoid version conflicts?

hard

A. Set strategy.type: Recreate to delete old pods before new ones

B. Set strategy.type: RollingUpdate with maxSurge=1

C. Use kubectl rollout restart without changing strategy

D. Set strategy.type: BlueGreen for zero downtime

Solution

1. Step 1: Identify app requirement

   The app cannot run multiple versions at the same time, so pods must not overlap.

2. Step 2: Choose update strategy

   Recreate deletes old pods before creating new ones, ensuring no version overlap.

3. Step 3: Rule out other options

   RollingUpdate allows overlapping versions, kubectl restart doesn't change strategy, BlueGreen is not a built-in Kubernetes strategy.

4. Final Answer:

   Set strategy.type: Recreate to delete old pods before new ones -> Option A

5. Quick Check:

   App needs no overlap = use Recreate [OK]

Hint: Use Recreate strategy to avoid running multiple versions [OK]

Common Mistakes:

• Choosing RollingUpdate which allows overlap
• Thinking kubectl restart changes update strategy
• Assuming BlueGreen is a native Kubernetes strategy