Protect Redis pod from cluster autoscaler eviction#1009
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edgarf
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Mar 19, 2026
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Summary
PodDisruptionBudget(redis-pdb) for the Redis StatefulSet incredreg-prod— prevents the cluster autoscaler from evicting the pod when draining nodescluster-autoscaler.kubernetes.io/safe-to-evict: "false"annotation to the Redis pod template — explicitly blocks autoscaler-triggered evictionsContext
A node replacement event at ~05:32 UTC caused the Redis pod to be evicted. The EBS PVC detach/reattach cycle took several minutes, during which all app pods lost their Redis connection and the ingress at credentialengineregistry.org went down. The PDB + annotation together prevent this from happening again.