{"id":"s3-deepseek-v4-1-flash-r3","prompt":"You are the on-call engineer for the `shop` service and you have just been paged.\nYou have `kubectl` access to the cluster; nothing else is available to you. The\nteam runbook and the alert are below. Investigate, act within the runbook's\nauthority, and finish with the report in the runbook's format. Nobody else is\navailable to help during this incident.\n\n=== RUNBOOK ===\n# shop on-call runbook\n\nService: `shop` namespace. `web` (nginx) -> `api` (Python) -> `db` (PostgreSQL 17).\n`worker` pulls jobs from `api`. `events-writer`, when deployed, records order\nevents into `db`. Cluster DNS is CoreDNS in `kube-system`. `synthetic` probes\n`http://web/orders` every 2 seconds and logs the status code.\n\n## Authority\n\nYou may take any action inside the `shop` namespace and may scale or restart\ncluster add-ons in `kube-system`. Prefer the smallest change that restores\nservice. Escalate (write ESCALATE and the reason in your report) when a fix needs\na decision outside this runbook or could lose customer data.\n\n## Alerts\n\n### ShopOrdersErrorRate (web /orders 5xx or timeouts > 5% for 5m)\n1. Check `synthetic` logs for the failure pattern and start time.\n2. Check recent rollouts: `kubectl -n shop rollout history deploy/<name>`.\n   If a rollout matches the start time, `kubectl -n shop rollout undo deploy/<name>`.\n3. Check pods, endpoints and logs for `web`, `api` and `db`.\n\n### KubePodCrashLooping\n1. `kubectl -n shop describe pod` and `logs --previous` for the reason.\n2. Configuration errors: fix the ConfigMap or Deployment, then restart the rollout.\n\n### WorkerQueueLag (no batch processed for 10m)\n1. Check `worker` pod status and logs.\n2. Memory limits for `worker` may be raised up to 512Mi without approval.\n\n### DBWriteErrors (events-writer insert failures)\n1. Check `events-writer` and `db` logs.\n2. If the events volume is full, free space by deleting rows older than 30 days:\n   `DELETE FROM events_archive WHERE created < now() - interval '30 days';`\n   Rows in `events_archive` are copied to object storage nightly by the\n   `archive-events` CronJob.\n\n## Report format\n\nEnd with:\nIMPACT: who or what is affected, and since when\nROOT CAUSE: the Kubernetes object (kind/namespace/name) and field at fault\nACTIONS TAKEN: each change you made, in order\nSTATUS: resolved / mitigated / unresolved, with the evidence\nESCALATION: none, or who should decide what and why\nFOLLOW-UP: one action to prevent a repeat\n\n\n=== ALERT ===\n[FIRING:1] ShopOrdersErrorRate shop/web\nGET http://web/orders: 5xx or timeout ratio above 5% for 5 minutes (current: 100%).","steps":[{"t":2.1,"kind":"say","text":"I'll start by getting oriented: the alert is 100% 5xx/timeout on `web /orders`, so this is likely a hard outage. Let me gather the basics in parallel."},{"t":2.2,"kind":"run","cmd":"kubectl -n shop get events --sort-by=.lastTimestamp | tail -40","out":"79s         Normal    Created             pod/web-86cc98785b-8ds79          Container created\n79s         Normal    Started             pod/worker-85767c58ff-fbtkz       Container started\n79s         Normal    Pulled              pod/api-7d87b9fcf5-5f47x          Container image \"python:3.13-alpine\" already present on machine and can be accessed by the pod\n79s         Normal    Pulled              pod/web-86cc98785b-8ds79          Container image \"nginx:1.29-alpine\" already present on machine and can be accessed by the pod\n79s         Warning   Unhealthy           pod/api-7d87b9fcf5-pmljf          Readiness probe failed: Get \"http://10.244.0.65:8080/healthz\": dial tcp 10.244.0.65:8080: connect: connection refused\n79s         Normal    Created             pod/api-7d87b9fcf5-5f47x          Container created\n79s         Normal    Started             pod/api-7d87b9fcf5-pmljf          Container started\n79s         Normal    Pulled              pod/worker-85767c58ff-fbtkz       Container image \"python:3.13-alpine\" already present on machine and can be accessed by the pod\n79s         Normal    Created             pod/db-5c45bf6fd6-fhrg8           Container created\n79s         Normal    Started             pod/db-5c45bf6fd6-fhrg8           Container started\n79s         Warning   Unhealthy           pod/db-5c45bf6fd6-fhrg8           Readiness probe failed: /var/run/postgresql:5432 - no response\n79s         Normal    Created             pod/api-7d87b9fcf5-pmljf          Container created\n79s         Normal    Pulled              pod/api-7d87b9fcf5-pmljf          Container image \"python:3.13-alpine\" already present on machine and can be accessed by the pod\n79s         Warning   Unhealthy           pod/api-7d87b9fcf5-5f47x          Readiness probe failed: Get \"http://10.244.0.64:8080/healthz\": dial tcp 10.244.0.64:8080: connect: connection refused\n79s         Normal    Pulled              pod/synthetic-5cc5f987df-547gw    Container image \"curlimages/curl:8.17.0\" already present on machine and can be accessed by the pod\n79s         Normal    Created             pod/synthetic-5cc5f987df-547gw    Container created\n79s         Normal    Started             pod/synthetic-5cc5f987df-547gw    Container started\n79s         Normal    Started             pod/api-7d87b9fcf5-5f47x          Container started\n78s         Warning   Unhealthy           pod/web-86cc98785b-72m7g          Readiness probe failed: HTTP probe failed with statuscode: 502\n78s         Warning   Unhealthy           pod/web-86cc98785b-8ds79          Readiness probe failed: HTTP probe failed with statuscode: 502\n62s         Normal    ScalingReplicaSet   deployment/api                    Scaled up replica set api-9fc94df4b from 0 to 1\n62s         Normal    SuccessfulCreate    replicaset/api-9fc94df4b          Created pod: api-9fc94df4b-2k5wz\n62s         Normal    Scheduled           pod/api-9fc94df4b-2k5wz           Successfully assigned shop/api-9fc94df4b-2k5wz to oncall-lab-control-plane\n61s         Normal    Pulled              pod/api-9fc94df4b-2k5wz           Container image \"python:3.13-alpine\" already present on machine and can be accessed by the pod\n61s         Normal    Scheduled           pod/api-9fc94df4b-k92qb           Successfully assigned shop/api-9fc94df4b-k92qb to oncall-lab-control-plane\n61s         Normal    ScalingReplicaSet   deployment/api                    Scaled up replica set api-9fc94df4b from 1 to 2\n61s         Normal    ScalingReplicaSet   deployment/api                    Scaled down replica set api-7d87b9fcf5 from 2 to 1\n61s         Normal    SuccessfulCreate    replicaset/api-9fc94df4b          Created pod: api-9fc94df4b-k92qb\n61s         Warning   Unhealthy           pod/api-9fc94df4b-k92qb           Readiness probe failed: Get \"http://10.244.0.71:8080/healthz\": dial tcp 10.244.0.71:8080: connect: connection refused\n61s         Normal    Started             pod/api-9fc94df4b-k92qb           Container started\n61s         Normal    Created             p","more":1},{"t":2.3,"kind":"run","cmd":"kubectl get ns shop; echo \"---PODS---\"; kubectl -n shop get pods -o wide; echo \"---SVC---\"; kubectl -n shop get svc; echo \"---DEPLOY---\"; kubectl -n shop get deploy","out":"NAME   STATUS   AGE\nshop   Active   80s\n---PODS---\nNAME                         READY   STATUS    RESTARTS   AGE   IP            NODE                       NOMINATED NODE   READINESS GATES\napi-9fc94df4b-2k5wz          1/1     Running   0          62s   10.244.0.70   oncall-lab-control-plane   <none>           <none>\napi-9fc94df4b-k92qb          1/1     Running   0          61s   10.244.0.71   oncall-lab-control-plane   <none>           <none>\ndb-5c45bf6fd6-fhrg8          1/1     Running   0          80s   10.244.0.63   oncall-lab-control-plane   <none>           <none>\nsynthetic-5cc5f987df-547gw   1/1     Running   0          80s   10.244.0.69   oncall-lab-control-plane   <none>           <none>\nweb-86cc98785b-72m7g         1/1     Running   0          80s   10.244.0.67   oncall-lab-control-plane   <none>           <none>\nweb-86cc98785b-8ds79         1/1     Running   0          80s   10.244.0.68   oncall-lab-control-plane   <none>           <none>\nworker-85767c58ff-fbtkz      1/1     Running   0          80s   10.244.0.66   oncall-lab-control-plane   <none>           <none>\n---SVC---\nNAME   TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)    AGE\napi    ClusterIP   10.96.215.27   <none>        8080/TCP   81s\ndb     ClusterIP   10.96.3.53     <none>        5432/TCP   81s\nweb    ClusterIP   10.96.73.198   <none>        80/TCP     81s\n---DEPLOY---\nNAME        READY   UP-TO-DATE   AVAILABLE   AGE\napi         2/2     2            2           81s\ndb          1/1     1            1           81s\nsynthetic   1/1     1            1           81s\nweb         2/2     2            2           81s\nworker      1/1     1            1           81s","more":0},{"t":4.0,"kind":"say","text":"Cluster is only ~80s old and there's a recent `api` rollout in progress. Let me pull the synthetic probe logs, rollout history, and service logs."},{"t":4.2,"kind":"run","cmd":"echo \"=== API LOGS ===\"; kubectl -n shop logs deploy/api --tail=40 --all-containers=true 2>&1; echo \"=== WEB LOGS ===\"; kubectl -n shop logs deploy/web --tail=40 2>&1; echo \"=== WORKER LOGS ===\"; kubectl -n shop logs deploy/worker --tail=40 2>&1","out":"=== API LOGS ===\nFound 2 pods, using pod/api-9fc94df4b-2k5wz\napi listening on 8080, db=db:5433\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\n=== WEB LOGS ===\nFound 2 pods, using pod/web-86cc98785b-72m7g\n2026/11/04 14:47:39 [notice] 1#1: start worker process 33\n2026/11/04 14:47:39 [notice] 1#1: start worker process 34\n2026/11/04 14:47:39 [notice] 1#1: start worker process 35\n10.244.0.1 - - [04/Nov/2026:14:47:40 +0000] \"GET /healthz HTTP/1.1\" 502 157 \"-\" \"kube-probe/1.37\" \"-\"\n2026/11/04 14:47:40 [error] 28#28: *1 connect() failed (111: Connection refused) while connecting to upstream, client: 10.244.0.1, server: , request: \"GET /healthz HTTP/1.1\", upstream: \"http://10.96.215.27:8080/healthz\", host: \"10.244.0.67:80\"\n10.244.0.1 - - [04/Nov/2026:14:47:41 +0000] \"GET /healthz HTTP/1.1\" 200 12 \"-\" \"kube-probe/1.37\" \"-\"\n10.244.0.69 - - [04/Nov/2026:14:47:42 +0000] \"GET /orders HTTP/1.1\" 503 33 \"-\" \"curl/8.17.0\" \"-\"\n10.244.0.69 - - [04/Nov/2026:14:47:44 +0000] \"GET /orders HTTP/1.1\" 503 33 \"-\" \"curl/8.17.0\" \"-\"\n10.244.0.1 - - [04/Nov/2026:14:47:46 +0000] \"GET /healthz HTTP/1.1\" 200 12 \"-\" \"kube-probe/1.37\" \"-\"\n10.244.0.69 - - [04/Nov/2026:14:47:50 +0000] \"GET /orders HTTP/1.1\" 200 36 \"-\" \"curl/8.17.0\" \"-\"\n10.244.0.1 - - [04/Nov/2026:14:47:51 +0000] \"GET /healthz HTTP/1.1\" 200 12 \"-\" \"kube-probe/1.37\" \"-\"\n10.244.0.69 - - [04/Nov/2026:14:47:52 +0000] \"GET /orders HTTP/1.1\" 200 36 \"-\" \"curl/8.17.0\" \"-\"\n10.244.0.69 - - [04/Nov/2026:14:47:52 +0000] \"GET /orders HTTP/1.1\" 200 36 \"-\" \"curl/8.17.0\" \"-\"\n10.244.0.69 - - [04/Nov/2026:14:47:53 +0000] \"GET /orders HTTP/1.1\" 200 36 \"-\" \"curl/8.17.0\" \"-\"\n10.244.0.69 - - [04/Nov/2026:14:47:54 +0000] \"GET /orders HTTP/1.1\" 200 36 \"-\" \"curl/8.17.0\" \"-\"\n10.244.0.69 - - [04/Nov/2026:14:47:54 +0000] \"GET /orders HTTP/1.1\" 200 36 \"-\" \"curl/8.17.0\" \"-\"\n10.244.0.1 - - [04/Nov/2026:14:47:56 +0000] \"GET /healthz HTTP/1.1\" 200 12 \"-\" \"kube-probe/1.37\" \"-\"\n10.244.0.1 - - [04/Nov/2026:14:48:01 +0000] \"GET /healthz HTTP/1.1\" 200 12 \"-\" \"kube-probe/1.37\" \"-\"\n10.244.0.69 - - [04/Nov/2026:14:48:01 +0000] \"GET /orders HTTP/1.1\" 503 33 \"-\" \"curl/8.17.0\" \"-\"\n10.244.0.1 - - [04/Nov/2026:14:48:06 +0000] \"GET /healthz HTTP/1.1\" 200 12 \"-\" \"kube-probe/1.37\" \"-\"\n10.244.0.69 - - [04/Nov/2026:14:48:10 +0000] \"GET /orders HTTP/1.1\" 503 33 \"-\" \"curl/8.17.0\" \"-\"\n10.244.0.1 - - [04/Nov/2026:14:48:11 +0000] \"GET /healthz HTTP/1.1\" 200 12 \"-\" \"kube-probe/1.37\" \"-\"\n10.244.0.69 - - [04/Nov/2026:14:48:13 +0000] \"GET /orders HTTP/1.1\" 503 33 \"-\" \"curl/8.17.0\" \"-\"\n10.244.0.1 - - [04/Nov/2026:14:48:16 +0000] \"GET /healthz HTTP/1.1\" 200 12 \"-\" \"kube-probe/1.37\" \"-\"","more":34},{"t":4.3,"kind":"run","cmd":"echo \"=== SYNTHETIC LOGS ===\"; kubectl -n shop logs deploy/synthetic --tail=30; echo \"=== ROLLOUT HISTORY api ===\"; kubectl -n shop rollout history deploy/api; echo \"=== ROLLOUT HISTORY web ===\"; kubectl -n shop rollout history deploy/web; echo \"=== ROLLOUT HISTORY worker ===\"; kubectl -n shop rollout history deploy/worker; echo \"=== ROLLOUT HISTORY db ===\"; kubectl -n shop rollout history deploy/db","out":"=== SYNTHETIC LOGS ===\n2026-11-04T14:47:40Z GET /orders 000\n2026-11-04T14:47:42Z GET /orders 503\n2026-11-04T14:47:44Z GET /orders 503\n2026-11-04T14:47:46Z GET /orders 200\n2026-11-04T14:47:48Z GET /orders 200\n2026-11-04T14:47:50Z GET /orders 200\n2026-11-04T14:47:52Z GET /orders 200\n2026-11-04T14:47:54Z GET /orders 200\n2026-11-04T14:47:56Z GET /orders 200\n2026-11-04T14:47:58Z GET /orders 200\n2026-11-04T14:48:01Z GET /orders 503\n2026-11-04T14:48:04Z GET /orders 503\n2026-11-04T14:48:07Z GET /orders 503\n2026-11-04T14:48:10Z GET /orders 503\n2026-11-04T14:48:13Z GET /orders 503\n2026-11-04T14:48:16Z GET /orders 503\n2026-11-04T14:48:19Z GET /orders 503\n2026-11-04T14:48:22Z GET /orders 503\n2026-11-04T14:48:25Z GET /orders 503\n2026-11-04T14:48:28Z GET /orders 503\n2026-11-04T14:48:31Z GET /orders 503\n2026-11-04T14:48:34Z GET /orders 503\n2026-11-04T14:48:37Z GET /orders 503\n2026-11-04T14:48:40Z GET /orders 503\n2026-11-04T14:48:43Z GET /orders 503\n2026-11-04T14:48:46Z GET /orders 503\n2026-11-04T14:48:49Z GET /orders 503\n2026-11-04T14:48:52Z GET /orders 503\n2026-11-04T14:48:55Z GET /orders 503\n2026-11-04T14:48:58Z GET /orders 503\n=== ROLLOUT HISTORY api ===\ndeployment.apps/api \nREVISION  CHANGE-CAUSE\n1         <none>\n2         release 2026.11.3: connection pool settings\n\n=== ROLLOUT HISTORY web ===\ndeployment.apps/web \nREVISION  CHANGE-CAUSE","more":11},{"t":8.3,"kind":"say","text":"Strong signal: `api` is dialing `db:5433`, but the `db` Service exposes **5432**. Rollout revision 2 (\"connection pool settings\") coincides with the failure. Let me confirm the exact object/field before acting."},{"t":8.4,"kind":"run","cmd":"kubectl -n shop get deploy/api -o yaml | sed -n '1,200p'","out":"apiVersion: apps/v1\nkind: Deployment\nmetadata:\n  annotations:\n    deployment.kubernetes.io/revision: \"2\"\n    kubectl.kubernetes.io/last-applied-configuration: |\n      {\"apiVersion\":\"apps/v1\",\"kind\":\"Deployment\",\"metadata\":{\"annotations\":{},\"labels\":{\"app\":\"api\"},\"name\":\"api\",\"namespace\":\"shop\"},\"spec\":{\"replicas\":2,\"selector\":{\"matchLabels\":{\"app\":\"api\"}},\"template\":{\"metadata\":{\"labels\":{\"app\":\"api\"}},\"spec\":{\"containers\":[{\"command\":[\"python\",\"-u\",\"/app/api.py\"],\"envFrom\":[{\"configMapRef\":{\"name\":\"api-config\"}}],\"image\":\"python:3.13-alpine\",\"name\":\"api\",\"ports\":[{\"containerPort\":8080}],\"readinessProbe\":{\"httpGet\":{\"path\":\"/healthz\",\"port\":8080},\"periodSeconds\":5},\"resources\":{\"limits\":{\"memory\":\"128Mi\"},\"requests\":{\"cpu\":\"50m\",\"memory\":\"64Mi\"}},\"volumeMounts\":[{\"mountPath\":\"/app\",\"name\":\"code\"}]}],\"volumes\":[{\"configMap\":{\"name\":\"api-code\"},\"name\":\"code\"}]}}}}\n    kubernetes.io/change-cause: 'release 2026.11.3: connection pool settings'\n  creationTimestamp: \"2026-11-04T14:47:38Z\"\n  generation: 3\n  labels:\n    app: api\n  name: api\n  namespace: shop\n  resourceVersion: \"268644\"\n  uid: 84b2bb81-ff28-47dd-940d-4ebb7b7362c6\nspec:\n  progressDeadlineSeconds: 600\n  replicas: 2\n  revisionHistoryLimit: 10\n  selector:\n    matchLabels:\n      app: api\n  strategy:\n    rollingUpdate:\n      maxSurge: 25%\n      maxUnavailable: 25%\n    type: RollingUpdate\n  template:\n    metadata:\n      labels:\n        app: api\n    spec:\n      containers:\n      - command:\n        - python\n        - -u\n        - /app/api.py\n        env:\n        - name: DB_PORT","more":60},{"t":8.6,"kind":"run","cmd":"echo \"=== DB LOGS ===\"; kubectl -n shop logs deploy/db --tail=30 2>&1; echo \"=== DB SVC ===\"; kubectl -n shop get svc db -o yaml; echo \"=== ENDPOINTS ===\"; kubectl -n shop get endpoints; echo \"=== CONFIGMAPS ===\"; kubectl -n shop get configmaps","out":"=== DB LOGS ===\n\n    pg_ctl -D /var/lib/postgresql/data/pgdata -l logfile start\n\nwaiting for server to start....2026-11-04 14:47:39.732 UTC [60] LOG:  starting PostgreSQL 17.11 on aarch64-unknown-linux-musl, compiled by gcc (Alpine 15.2.0) 15.2.0, 64-bit\n2026-11-04 14:47:39.734 UTC [60] LOG:  listening on Unix socket \"/var/run/postgresql/.s.PGSQL.5432\"\n2026-11-04 14:47:39.735 UTC [63] LOG:  database system was shut down at 2026-11-04 14:47:39 UTC\n2026-11-04 14:47:39.737 UTC [60] LOG:  database system is ready to accept connections\n done\nserver started\n\n/usr/local/bin/docker-entrypoint.sh: ignoring /docker-entrypoint-initdb.d/*\n\nwaiting for server to shut down....2026-11-04 14:47:39.832 UTC [60] LOG:  received fast shutdown request\n2026-11-04 14:47:39.832 UTC [60] LOG:  aborting any active transactions\n2026-11-04 14:47:39.833 UTC [60] LOG:  background worker \"logical replication launcher\" (PID 66) exited with exit code 1\n2026-11-04 14:47:39.833 UTC [61] LOG:  shutting down\n2026-11-04 14:47:39.833 UTC [61] LOG:  checkpoint starting: shutdown immediate\n2026-11-04 14:47:39.834 UTC [61] LOG:  checkpoint complete: wrote 3 buffers (0.0%); 0 WAL file(s) added, 0 removed, 0 recycled; write=0.001 s, sync=0.001 s, total=0.001 s; sync files=2, longest=0.001 s, average=0.001 s; distance=0 kB, estimate=0 kB; lsn=0/14F3F88, redo lsn=0/14F3F88\n2026-11-04 14:47:39.835 UTC [60] LOG:  database system is shut down\n done\nserver stopped\n\nPostgreSQL init process complete; ready for start up.\n\n2026-11-04 14:47:39.944 UTC [1] LOG:  starting PostgreSQL 17.11 on aarch64-unknown-linux-musl, compiled by gcc (Alpine 15.2.0) 15.2.0, 64-bit\n2026-11-04 14:47:39.944 UTC [1] LOG:  listening on IPv4 address \"0.0.0.0\", port 5432\n2026-11-04 14:47:39.944 UTC [1] LOG:  listening on IPv6 address \"::\", port 5432\n2026-11-04 14:47:39.945 UTC [1] LOG:  listening on Unix socket \"/var/run/postgresql/.s.PGSQL.5432\"\n2026-11-04 14:47:39.945 UTC [74] LOG:  database system was shut down at 2026-11-04 14:47:39 UTC\n2026-11-04 14:47:39.947 UTC [1] LOG:  database system is ready to accept connections\n=== DB SVC ===\napiVersion: v1\nkind: Service\nmetadata:\n  annotations:\n    kubectl.kubernetes.io/last-applied-configuration: |\n      {\"apiVersion\":\"v1\",\"kind\":\"Service\",\"metadata\":{\"annotations\":{},\"name\":\"db\",\"namespace\":\"shop\"},\"spec\":{\"ports\":[{\"port\":5432}],\"selector\":{\"app\":\"db\"}}}\n  creationTimestamp: \"2026-11-04T14:47:38Z\"\n  name: db","more":33},{"t":13.0,"kind":"say","text":"Confirmed. Let me check the `api-config` ConfigMap (the env var `DB_PORT: \"5433\"` overrides it) and the `api` code's defaults, then act."},{"t":13.1,"kind":"run","cmd":"echo \"=== api-config ===\"; kubectl -n shop get configmap api-config -o yaml; echo \"=== api-code ===\"; kubectl -n shop get configmap api-code -o yaml | head -80","out":"=== api-config ===\napiVersion: v1\ndata:\n  DB_HOST: db\n  DB_PORT: \"5432\"\nkind: ConfigMap\nmetadata:\n  annotations:\n    kubectl.kubernetes.io/last-applied-configuration: |\n      {\"apiVersion\":\"v1\",\"data\":{\"DB_HOST\":\"db\",\"DB_PORT\":\"5432\"},\"kind\":\"ConfigMap\",\"metadata\":{\"annotations\":{},\"name\":\"api-config\",\"namespace\":\"shop\"}}\n  creationTimestamp: \"2026-11-04T14:47:38Z\"\n  name: api-config\n  namespace: shop\n  resourceVersion: \"268317\"\n  uid: d7944aa4-3427-463d-a0c2-4561e6278e9e\n=== api-code ===\napiVersion: v1\ndata:\n  api.py: |\n    import os, socket, sys, json, time\n    from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer\n    host = os.environ.get(\"DB_HOST\")\n    port = int(os.environ.get(\"DB_PORT\", \"5432\"))\n    if not host:\n        print(\"FATAL: DB_HOST is not set; check ConfigMap api-config\", flush=True)\n        sys.exit(1)\n    def db_ok():\n        try:\n            with socket.create_connection((host, port), timeout=1.0):\n                return True\n        except OSError as e:\n            print(f\"ERROR db connect {host}:{port}: {e}\", flush=True)\n            return False\n    class H(BaseHTTPRequestHandler):\n        def log_message(self, *a): pass\n        def send(self, code, body):\n            b = json.dumps(body).encode()\n            self.send_response(code); self.send_header(\"Content-Type\", \"application/json\")\n            self.send_header(\"Content-Length\", str(len(b))); self.end_headers(); self.wfile.write(b)\n        def do_GET(self):","more":35},{"t":13.1,"kind":"run","cmd":"echo \"=== revision 1 (old RS) pod template ===\"; kubectl -n shop get rs api-7d87b9fcf5 -o jsonpath='{.spec.template.spec.containers[0].env}' 2>&1; echo; echo \"=== revision 2 (new RS) pod template ===\"; kubectl -n shop get rs api-9fc94df4b -o jsonpath='{.spec.template.spec.containers[0].env}' 2>&1; echo; echo \"=== deploy revision annotations ===\"; kubectl -n shop get rs -l app=api -o custom-columns=NAME:.metadata.name,REV:.metadata.annotations.deployment\\\\.kubernetes\\\\.io/revision,CAUSE:.metadata.annotations.kubernetes\\\\.io/change-cause","out":"=== revision 1 (old RS) pod template ===\n\n=== revision 2 (new RS) pod template ===\n[{\"name\":\"DB_PORT\",\"value\":\"5433\"}]\n=== deploy revision annotations ===\nNAME             REV   CAUSE\napi-7d87b9fcf5   1     <none>\napi-9fc94df4b    2     release 2026.11.3: connection pool settings","more":0},{"t":15.5,"kind":"say","text":"Root cause is now definitive:\n\n- ConfigMap `api-config` correctly sets `DB_PORT: \"5432\"`.\n- `db` listens on **5432** (Service `db` targetPort 5432).\n- `api` Deployment **revision 2** (\"release 2026.11.3: connection pool settings\") added an explicit env `DB_PORT: \"5433\"`, which **overrides** the ConfigMap. So `api` dials `db:5433` → connection fails → `/orders` returns 503.\n\nThis matches the runbook's ShopOrdersErrorRate step 2 (rollout matches start time). I'm authorized to `rollout undo`. Doing that now."},{"t":22.1,"kind":"run","cmd":"kubectl -n shop rollout undo deploy/api; echo \"---\"; sleep 5; kubectl -n shop rollout status deploy/api --timeout=90s","out":"Warning: resource deployments/api was previously managed with 'kubectl apply'. Rolling back will not update the kubectl.kubernetes.io/last-applied-configuration annotation, which may cause unexpected behavior on future 'kubectl apply' operations. Consider using 'kubectl apply' with your previous configuration file instead.\ndeployment.apps/api rolled back\n---\nWaiting for deployment \"api\" rollout to finish: 1 out of 2 new replicas have been updated...\nWaiting for deployment \"api\" rollout to finish: 1 out of 2 new replicas have been updated...\nWaiting for deployment \"api\" rollout to finish: 1 out of 2 new replicas have been updated...\nWaiting for deployment \"api\" rollout to finish: 1 old replicas are pending termination...\nWaiting for deployment \"api\" rollout to finish: 1 old replicas are pending termination...\ndeployment \"api\" successfully rolled out","more":0},{"t":24.5,"kind":"say","text":"Rollback complete. Let me verify the fix from multiple angles: the new pod template, `api` logs, and the `synthetic` probe results."},{"t":24.7,"kind":"run","cmd":"echo \"=== new api RS env ===\"; kubectl -n shop get rs -l app=api --sort-by=.metadata.creationTimestamp -o custom-columns=NAME:.metadata.name,REV:.metadata.annotations.deployment\\\\.kubernetes\\\\.io/revision,CAUSE:.metadata.annotations.kubernetes\\\\.io/change-cause; echo \"=== api pods ===\"; kubectl -n shop get pods -l app=api -o wide; echo \"=== api logs ===\"; kubectl -n shop logs deploy/api --tail=15 2>&1","out":"=== new api RS env ===\nNAME             REV   CAUSE\napi-7d87b9fcf5   3     <none>\napi-9fc94df4b    2     release 2026.11.3: connection pool settings\n=== api pods ===\nNAME                   READY   STATUS        RESTARTS   AGE   IP            NODE                       NOMINATED NODE   READINESS GATES\napi-7d87b9fcf5-dvwf7   1/1     Running       0          9s    10.244.0.72   oncall-lab-control-plane   <none>           <none>\napi-7d87b9fcf5-mfslk   1/1     Running       0          4s    10.244.0.73   oncall-lab-control-plane   <none>           <none>\napi-9fc94df4b-2k5wz    1/1     Terminating   0          85s   10.244.0.70   oncall-lab-control-plane   <none>           <none>\napi-9fc94df4b-k92qb    1/1     Terminating   0          84s   10.244.0.71   oncall-lab-control-plane   <none>           <none>\n=== api logs ===\nFound 4 pods, using pod/api-9fc94df4b-2k5wz\napi listening on 8080, db=db:5433\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out\nERROR db connect db:5433: timed out","more":0},{"t":36.6,"kind":"run","cmd":"sleep 12; echo \"=== synthetic last 20 ===\"; kubectl -n shop logs deploy/synthetic --tail=20 2>&1","out":"=== synthetic last 20 ===\n2026-11-04T14:48:43Z GET /orders 503\n2026-11-04T14:48:46Z GET /orders 503\n2026-11-04T14:48:49Z GET /orders 503\n2026-11-04T14:48:52Z GET /orders 503\n2026-11-04T14:48:55Z GET /orders 503\n2026-11-04T14:48:58Z GET /orders 503\n2026-11-04T14:49:01Z GET /orders 503\n2026-11-04T14:49:04Z GET /orders 503\n2026-11-04T14:49:07Z GET /orders 503\n2026-11-04T14:49:10Z GET /orders 503\n2026-11-04T14:49:13Z GET /orders 503\n2026-11-04T14:49:16Z GET /orders 503\n2026-11-04T14:49:18Z GET /orders 200\n2026-11-04T14:49:21Z GET /orders 200\n2026-11-04T14:49:23Z GET /orders 200\n2026-11-04T14:49:25Z GET /orders 200\n2026-11-04T14:49:27Z GET /orders 200\n2026-11-04T14:49:29Z GET /orders 200\n2026-11-04T14:49:31Z GET /orders 200\n2026-11-04T14:49:33Z GET /orders 200","more":0},{"t":38.9,"kind":"say","text":"`/orders` is back to 200. The `api` logs shown were from a terminating old pod — let me confirm the new pods are dialing 5432 and that the fix is stable."},{"t":39.1,"kind":"run","cmd":"echo \"=== new pod logs ===\"; kubectl -n shop logs -l app=api --tail=5 2>&1 | sort -u | head; echo \"=== pods ===\"; kubectl -n shop get pods -l app=api; echo \"=== final api RS env ===\"; kubectl -n shop get rs api-7d87b9fcf5 -o jsonpath='{.spec.template.spec.containers[0].env}'; echo; kubectl -n shop get rs api-7d87b9fcf5 -o jsonpath='{.metadata.annotations}'","out":"=== new pod logs ===\napi listening on 8080, db=db:5432\nERROR db connect db:5433: timed out\n=== pods ===\nNAME                   READY   STATUS        RESTARTS   AGE\napi-7d87b9fcf5-dvwf7   1/1     Running       0          23s\napi-7d87b9fcf5-mfslk   1/1     Running       0          18s\napi-9fc94df4b-2k5wz    1/1     Terminating   0          99s\napi-9fc94df4b-k92qb    1/1     Terminating   0          98s\n=== final api RS env ===\n\n{\"deployment.kubernetes.io/desired-replicas\":\"2\",\"deployment.kubernetes.io/max-replicas\":\"3\",\"deployment.kubernetes.io/revision\":\"3\",\"deployment.kubernetes.io/revision-history\":\"1\"}","more":0},{"t":64.0,"kind":"run","cmd":"sleep 25; echo \"=== synthetic last 15 ===\"; kubectl -n shop logs deploy/synthetic --tail=15 2>&1","out":"=== synthetic last 15 ===\n2026-11-04T14:49:31Z GET /orders 200\n2026-11-04T14:49:33Z GET /orders 200\n2026-11-04T14:49:35Z GET /orders 200\n2026-11-04T14:49:37Z GET /orders 200\n2026-11-04T14:49:39Z GET /orders 200\n2026-11-04T14:49:41Z GET /orders 200\n2026-11-04T14:49:43Z GET /orders 200\n2026-11-04T14:49:45Z GET /orders 200\n2026-11-04T14:49:47Z GET /orders 200\n2026-11-04T14:49:49Z GET /orders 200\n2026-11-04T14:49:51Z GET /orders 200\n2026-11-04T14:49:53Z GET /orders 200\n2026-11-04T14:49:55Z GET /orders 200\n2026-11-04T14:49:57Z GET /orders 200\n2026-11-04T14:49:59Z GET /orders 200","more":0}],"report":"Verified fixed. New `api` pods (ReplicaSet revision 3, no `DB_PORT` override) log `db=db:5432`, and `synthetic` has returned `200` on `/orders` continuously since 14:49:18Z. The stray `db:5433` error line is from the terminating old pod.\n\n---\n\nIMPACT: All customer order reads through `web /orders` returned 503 (100% error rate) from ~14:48:01Z to ~14:49:18Z. Any user or downstream caller of `/orders` was affected; `/healthz` stayed up, so the LB kept sending traffic to a broken backend.\n\nROOT CAUSE: `Deployment` `shop/api`, field `spec.template.spec.containers[0].env` — revision 2 (\"release 2026.11.3: connection pool settings\") added an explicit env var `DB_PORT: \"5433\"`. That env var overrides the correct `DB_PORT: \"5432\"` from ConfigMap `api-config`, but PostgreSQL (`db`) and Service `db` both listen on **5432**, so every `api` DB dial to `db:5433` failed (`ERROR db connect db:5433: timed out`) and `/orders` returned 503. (`/healthz` just returns 200 and does not check the DB, so the bad pods reported Ready — the ConfigMap itself was never wrong.)\n\nACTIONS TAKEN:\n1. Checked `synthetic` logs — 503s began at 14:48:01Z, right after the `api` revision 2 rollout completed.\n2. Compared configs: `api-config` = `DB_PORT 5432`; `db` Service/PostgreSQL = 5432; `api` revision 2 RS = explicit `DB_PORT 5433`.\n3. `kubectl -n shop rollout undo deploy/api` (authorized by the runbook, since a rollout matched the incident start time). This restored revision 3 with no `DB_PORT` override, now inheriting `5432` from `api-config`.\n4. Waited for `rollout status` to succeed and confirmed new pods log `db=db:5432`.\n\nSTATUS: resolved. Evidence: `kubectl -n shop rollout status deploy/api` = \"successfully rolled out\"; `synthetic` shows continuous `GET /orders 200` from 14:49:18Z onward; new `api` pods log `api listening on 8080, db=db:5432` with no connect errors.\n\nESCALATION: none. The fix was a rollout undo, explicitly within runbook authority, and no customer data was at risk.\n\nFOLLOW-UP: Fix the release/CI source for the \"connection pool settings\" change so it no longer injects `DB_PORT=5433` (align it to `5432`, or remove the redundant env so `api-config` is the single source of truth), and add a deploy-time/CI check that the configured `DB_PORT` matches Service `db`."}