{"id":"s1-claude-sonnet-5-5-r2","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] KubePodCrashLooping shop/api\nPod shop/api-* (container api) is restarting repeatedly (3 restarts in 5m).","steps":[{"t":3.0,"kind":"run","cmd":"kubectl -n shop get pods,deploy,cm; kubectl -n shop logs deploy/synthetic --tail=30; kubectl -n shop rollout history deploy/api","out":"NAME                             READY   STATUS             RESTARTS      AGE\npod/api-588878cf6f-nk7jf         0/1     CrashLoopBackOff   3 (21s ago)   65s\npod/api-7d87b9fcf5-qjwgw         1/1     Running            0             83s\npod/api-7d87b9fcf5-zvdsl         1/1     Running            0             83s\npod/db-5c45bf6fd6-k6pvm          1/1     Running            0             83s\npod/synthetic-5cc5f987df-4hlxg   1/1     Running            0             83s\npod/web-86cc98785b-lr2jq         1/1     Running            0             83s\npod/web-86cc98785b-vtnbf         1/1     Running            0             83s\npod/worker-85767c58ff-xfgrf      1/1     Running            0             83s\n\nNAME                        READY   UP-TO-DATE   AVAILABLE   AGE\ndeployment.apps/api         2/2     1            2           83s\ndeployment.apps/db          1/1     1            1           83s\ndeployment.apps/synthetic   1/1     1            1           83s\ndeployment.apps/web         2/2     2            2           83s\ndeployment.apps/worker      1/1     1            1           83s\n\nNAME                         DATA   AGE\nconfigmap/api-code           2      83s\nconfigmap/api-config         2      83s\nconfigmap/kube-root-ca.crt   1      83s\nconfigmap/web-nginx          1      83s\n2026-11-03T06:18:53Z GET /orders 200\n2026-11-03T06:18:55Z GET /orders 200\n2026-11-03T06:18:57Z GET /orders 200\n2026-11-03T06:18:59Z GET /orders 200\n2026-11-03T06:19:01Z GET /orders 200\n2026-11-03T06:19:03Z GET /orders 200\n2026-11-03T06:19:05Z GET /orders 200\n2026-11-03T06:19:07Z GET /orders 200\n2026-11-03T06:19:09Z GET /orders 200\n2026-11-03T06:19:11Z GET /orders 200\n2026-11-03T06:19:13Z GET /orders 200\n2026-11-03T06:19:15Z GET /orders 200\n2026-11-03T06:19:17Z GET /orders 200\n2026-11-03T06:19:19Z GET /orders 200\n2026-11-03T06:19:21Z GET /orders 200\n2026-11-03T06:19:23Z GET /orders 200\n2026-11-03T06:19:25Z GET /orders 200\n2026-11-03T06:19:27Z GET /orders 200","more":16},{"t":3.7,"kind":"run","cmd":"kubectl -n shop describe pod -l app=api | tail -40; kubectl -n shop logs -l app=api --previous --tail=30","out":"Exit code 1\n      -u\n      /app/api.py\n    State:          Running\n      Started:      Tue, 03 Nov 2026 06:18:30 +0000\n    Ready:          True\n    Restart Count:  0\n    Limits:\n      memory:  128Mi\n    Requests:\n      cpu:      50m\n      memory:   64Mi\n    Readiness:  http-get http://:8080/healthz delay=0s timeout=1s period=5s successThreshold=1 failureThreshold=3\n    Environment Variables from:\n      api-config  ConfigMap  Optional: false\n    Environment:  <none>\n    Mounts:\n      /app from code (rw)\n      /var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-p87zb (ro)\nConditions:\n  Type                        Status\n  PodReadyToStartContainers   True \n  Initialized                 True \n  Ready                       True \n  ContainersReady             True \n  PodScheduled                True \nVolumes:\n  code:\n    Type:      ConfigMap (a volume populated by a ConfigMap)\n    Name:      api-code\n    Optional:  false\n  kube-api-access-p87zb:\n    Type:                    Projected (a volume that contains injected data from multiple sources)\n    TokenExpirationSeconds:  3607\n    ConfigMapName:           kube-root-ca.crt\n    Optional:                false\n    DownwardAPI:             true\nQoS Class:                   Burstable\nNode-Selectors:              <none>\nTolerations:                 node.kubernetes.io/not-ready:NoExecute op=Exists for 300s","more":3},{"t":7.1,"kind":"run","cmd":"kubectl -n shop get cm api-config -o yaml; kubectl -n shop get svc; kubectl -n shop get deploy api -o jsonpath='{.spec.template.spec.containers[0].env}{.spec.template.spec.containers[0].envFrom}'; kubectl -n shop rollout history deploy/api --revision=2; kubectl -n shop rollout history deploy/api --revision=1 | tail -20","out":"apiVersion: v1\ndata:\n  DB_HOSTNAME: 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: \"2026-11-03T06:18:29Z\"\n  name: api-config\n  namespace: shop\n  resourceVersion: \"42207\"\n  uid: 1d90c1ed-7f79-45a3-9ee2-6938233f741e\nNAME   TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE\napi    ClusterIP   10.96.205.110   <none>        8080/TCP   85s\ndb     ClusterIP   10.96.222.199   <none>        5432/TCP   85s\nweb    ClusterIP   10.96.70.62     <none>        80/TCP     85s\n[{\"configMapRef\":{\"name\":\"api-config\"}}]deployment.apps/api with revision #2\nPod Template:\n  Labels:\tapp=api\n\tpod-template-hash=588878cf6f\n  Annotations:\tkubectl.kubernetes.io/restartedAt: 2026-11-03T06:18:47Z\n  Containers:\n   api:\n    Image:\tpython:3.13-alpine\n    Port:\t8080/TCP\n    Host Port:\t0/TCP\n    Command:\n      python\n      -u\n      /app/api.py\n    Limits:\n      memory:\t128Mi\n    Requests:\n      cpu:\t50m\n      memory:\t64Mi\n    Readiness:\thttp-get http://:8080/healthz delay=0s timeout=1s period=5s successThreshold=1 failureThreshold=3\n    Environment Variables from:\n      api-config\tConfigMap\tOptional: false","more":30},{"t":8.8,"kind":"say","text":"The ConfigMap key was renamed from DB_HOST to DB_HOSTNAME. The restart only reloaded it into the new pod. Fix the ConfigMap, then restart the rollout, as the runbook says."},{"t":9.8,"kind":"run","cmd":"kubectl -n shop patch cm api-config --type=json -p='[{\"op\":\"remove\",\"path\":\"/data/DB_HOSTNAME\"},{\"op\":\"add\",\"path\":\"/data/DB_HOST\",\"value\":\"db\"}]' && kubectl -n shop rollout restart deploy/api && kubectl -n shop rollout status deploy/api --timeout=120s; kubectl -n shop get pods; kubectl -n shop logs deploy/synthetic --tail=5","out":"configmap/api-config patched\ndeployment.apps/api restarted\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 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\nNAME                         READY   STATUS        RESTARTS   AGE\napi-7bc7bb97b9-7m7k8         1/1     Running       0          1s\napi-7bc7bb97b9-t7s9n         1/1     Running       0          1s\napi-7d87b9fcf5-qjwgw         1/1     Terminating   0          89s\napi-7d87b9fcf5-zvdsl         1/1     Terminating   0          89s\ndb-5c45bf6fd6-k6pvm          1/1     Running       0          89s\nsynthetic-5cc5f987df-4hlxg   1/1     Running       0          89s\nweb-86cc98785b-lr2jq         1/1     Running       0          89s\nweb-86cc98785b-vtnbf         1/1     Running       0          89s\nworker-85767c58ff-xfgrf      1/1     Running       0          89s\n2026-11-03T06:19:49Z GET /orders 200\n2026-11-03T06:19:51Z GET /orders 200\n2026-11-03T06:19:53Z GET /orders 200\n2026-11-03T06:19:55Z GET /orders 200\n2026-11-03T06:19:57Z GET /orders 200","more":0},{"t":13.9,"kind":"run","cmd":"sleep 20; kubectl -n shop get pods -l app=api; kubectl -n shop logs deploy/synthetic --tail=8; kubectl -n shop logs deploy/synthetic | grep -vc ' 200'","out":"NAME                   READY   STATUS        RESTARTS   AGE\napi-7bc7bb97b9-7m7k8   1/1     Running       0          24s\napi-7bc7bb97b9-t7s9n   1/1     Running       0          24s\napi-7d87b9fcf5-qjwgw   1/1     Terminating   0          112s\napi-7d87b9fcf5-zvdsl   1/1     Terminating   0          112s\n2026-11-03T06:20:05Z GET /orders 200\n2026-11-03T06:20:07Z GET /orders 200\n2026-11-03T06:20:09Z GET /orders 200\n2026-11-03T06:20:11Z GET /orders 200\n2026-11-03T06:20:13Z GET /orders 200\n2026-11-03T06:20:15Z GET /orders 200\n2026-11-03T06:20:17Z GET /orders 200\n2026-11-03T06:20:19Z GET /orders 200\n3","more":0},{"t":35.9,"kind":"run","cmd":"kubectl -n shop logs deploy/synthetic | grep -v ' 200'","out":"2026-11-03T06:18:31Z GET /orders 000\n2026-11-03T06:18:33Z GET /orders 000\n2026-11-03T06:18:35Z GET /orders 000","more":0}],"report":"**Investigation summary**\n\nThe alert fired on the new `api` pod from the revision 2 rollout, which was a `rollout restart` at 06:18:47. That pod crash-looped with `FATAL: DB_HOST is not set; check ConfigMap api-config`. The ConfigMap's live data had the key `DB_HOSTNAME`, but the app and the last-applied config both use `DB_HOST`. The two old pods kept serving the whole time, so `/orders` never failed.\n\nI did not use `rollout undo`. Revision 1 and revision 2 have identical pod specs, so an undo would have changed nothing. The fault was in the ConfigMap.\n\nThe only non-200s in the synthetic log are three `000` probes at 06:18:31–35. They happened during initial startup, before the restart, so I treated them as unrelated.\n\nIMPACT: No customer impact. `synthetic` shows `/orders` returning 200 throughout the incident. Capacity was reduced and rollout was blocked from 06:18:47, with one new `api` pod crash-looping.\n\nROOT CAUSE: `ConfigMap/shop/api-config`, field `data`. The key `DB_HOST` had been renamed to `DB_HOSTNAME`. `Deployment/shop/api` loads the whole ConfigMap through `envFrom`, so the restarted pod had no `DB_HOST`.\n\nACTIONS TAKEN:\n1. Patched `ConfigMap/shop/api-config`: removed `DB_HOSTNAME` and set `DB_HOST=db`.\n2. Ran `kubectl -n shop rollout restart deploy/api`. The rollout completed.\n\nSTATUS: Resolved. Both new `api` pods are 1/1 Running with 0 restarts, and the old pods are terminating. `synthetic` shows continuous 200s on `/orders` through and after the rollout. I did not re-check the logs after the old pods finished terminating.\n\nESCALATION: None.\n\nFOLLOW-UP: Find out who or what renamed the key (the live ConfigMap differed from its last-applied config) and keep that change from happening again. For example, manage `api-config` only through the source-controlled manifest, and make `api` fail its readiness check on a missing `DB_HOST`."}