Topic: kubernetes
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Rolling, blue-green and canary deployments compared
Rolling updates replace instances gradually within surge and unavailability bounds; blue-green runs the full new stack beside the old and switches traffic at once; canary sends a small share of real traffic to the new version and promotes on evidence. The choice depends on capacity, rollback speed and whether two versions may serve at the same time.
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ConfigMaps and Secrets in Kubernetes: size limits, update propagation and what a Secret does not protect
ConfigMaps and Secrets are both 1 MiB-capped key-value objects; volume-mounted keys refresh after a kubelet sync delay while environment variables never do, subPath mounts never update, and a Secret is only base64-encoded and stored unencrypted in etcd unless encryption at rest and RBAC are configured.
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Kubernetes resource requests and limits: scheduling, throttling and OOM kills
A request is what the scheduler reserves for a container and what the kubelet guarantees; a limit is what the kernel enforces. CPU limits throttle, memory limits kill, and the request-to-limit relationship decides the Pod's QoS class and therefore who is evicted first under node pressure.
Machine-readable: JSON