Abdullah Şamil Güser

Updates

Rolling Updates

Remember

Deployments

• replicas
  • Number of pod instances
• revisionHistoryLimit
  • Number of previous iterations to keep
• strategy
  • RollingUpdate : Cycle through updating pods
  • Recreate : All existing pods are killed before new ones are created

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There are two values that you can set to help you with this process:

• maxSurge
  • Maximum number of Pods that can be created over the desired number of Pods
  • Value or percentage
• maxUnavailable
  • Maximum number of Pods that can be unavailable during the update process
• Default strategy with maxSurge and maxUnavailable both set to 25%

kubectl - Rolling Updates Cheat Sheet

# Update a deployment
kubectl apply -f [definition.yaml]

# Get the progress of the update
kubectl rollout status [deploymentname]

# Get the history of the deployment
kubectl rollout history deployment [deploymentname]

# Rollback a deployment
kubectl rollout undo [deploymentname]

# Rollback to a revision number
kubectl rollout undo [deploymentname] --to-revision=[revision#]

Blue/Green Deployments

• Does not solve the new database schema problem entirely
• You need to over provision the cluster size