Upgrade Operations

# Check current node image versions
az aks nodepool show -g <rg> --cluster-name <cluster> -n <nodepool> \
  --query "{nodeImageVersion:nodeImageVersion, osType:osType}"

# Check available upgrades
az aks nodepool get-upgrades -g <rg> --cluster-name <cluster> --nodepool-name <nodepool>

# Upgrade node image (non-disruptive with surge)
az aks nodepool upgrade -g <rg> --cluster-name <cluster> -n <nodepool> --node-image-only

# Check for deprecated API usage before upgrading
kubectl get --raw /metrics | grep apiserver_requested_deprecated_apis

# Verify available upgrade paths (can only skip one minor version)
az aks get-upgrades -g <rg> -n <cluster> -o table

# Check control plane provisioning state
az aks show -g <rg> -n <cluster> --query "provisioningState"

# If stuck: check AKS diagnostics blade in portal
# Azure Portal -> AKS cluster -> Diagnose and solve problems -> Upgrade

# Check current maxSurge
az aks nodepool show -g <rg> --cluster-name <cluster> -n <nodepool> \
  --query "upgradeSettings.maxSurge"

az aks nodepool update -g <rg> --cluster-name <cluster> -n <nodepool> \
  --max-surge 33%

kubectl get pdb -A
kubectl describe pdb <pdb-name> -n <ns>