AWS Solutions Architect Associate
136 incident response problems that help with AWS Solutions Architect Associate prep.
Read first
When the CI cache restores the wrong dependency graphAn InfraTree guide that lays out the first signals to check, the CLI verification order, common misdiagnoses, and a safe recovery path when package.json, the lockfile, and artifacts no longer agree even after a cache hit.CI/CD3 min readWhen GitHub Actions succeeds but only the rollout failsAn InfraTree guide that lays out the first signals to check, the CLI verification order, common misdiagnoses, and a safe recovery path when the build logs look fine but the failure surfaces only on the target deploy cluster or runtime.CI/CD3 min readThe checking order when GitHub Actions succeeds but only the deploy failsAn InfraTree guide that lays out the first signals to check, the CLI verification order, common misdiagnoses, and a safe recovery path when the workflow is green but the failure happens only in the rollout, promotion, or health check stage.CI/CD3 min read
Recommended problems
Reviewed problems first, then problems with detailed scenarios.
CICD-001Finding the real failure point in GitHub Actions build logsA training scenario for isolating the true cause from logs where npm dependency conflicts and cache traces are mixed together.ReviewedCI/CDIntermediate20 minFreeCICD-007Builds failingA scenario that narrows down the root cause, centered on realigning the cache key strategy and lockfile consistency, in the situation of builds failing because the cache key gets tangled after a Node version upgrade.ReviewedCI/CDBeginner16 minFreeCICD-009Deployment failingA scenario that narrows down the root cause, centered on checking the permission-policy difference by event type, in the situation of a deployment failing because the secret is empty only on tag releases.ReviewedCI/CDIntermediate21 minFreeCICD-021Build cache key mismatch after lockfile updateA pipeline stays green on one branch and fails on another because the dependency cache key no longer matches the lockfile layout.ReviewedCI/CDBeginner17 minFreeDocker build cache not used: npm ci reruns even when only the README changedDocker build cache not used: npm ci reruns even is a hands-on troubleshooting drill. Order Dockerfile steps so the dependency layer stays cached. build-cache-hygiene needs to be checked by narrowing scope, recent change, and the current live signal before rollback. 실무에서는 build...ReviewedCI/CDBeginner3 minFreedocker push: denied: requested access to the resource is denieddocker push: denied: requested access to the resource is denied is a hands-on troubleshooting drill. Check which registry an image tag actually points to before debugging credentials. GitHub Container Image Delivery needs to be checked by narrowing scope, recent change, and th...ReviewedCI/CDBeginner14 minFree
All problems (136)
npm ci fails with EUSAGE: only the PR that edited package.jsonnpm ci fails with EUSAGE: only the PR that edited package.json is a hands-on troubleshooting drill. Fix the lock file when npm ci refuses to install. ci-cd-workflow-debugging needs to be checked by narrowing scope, recent change, and the current live signal before rollback. 실무...ReviewedCI/CDBeginner3 minFreeImagePullBackOff: new pods cannot pull the release imageImagePullBackOff: new pods cannot pull the release image is a hands-on troubleshooting drill. Read the pull event to see what the registry could not find. container-startup needs to be checked by narrowing scope, recent change, and the current live signal before rollback. 실무에서...ReviewedKubernetesBeginner3 minFreeDocker build cache not used: npm ci reruns even when only the README changedDocker build cache not used: npm ci reruns even is a hands-on troubleshooting drill. Order Dockerfile steps so the dependency layer stays cached. build-cache-hygiene needs to be checked by narrowing scope, recent change, and the current live signal before rollback. 실무에서는 build...ReviewedCI/CDBeginner3 minFreeExit code 137 (OOMKilled): a container restarts under loadExit code 137 (OOMKilled): a container restarts is a hands-on troubleshooting drill. Learn what OOMKilled and exit code 137 mean. kubernetes-workload-reliability needs to be checked by narrowing scope, recent change, and the current live signal before rollback. 실무에서는 CrashLoop...ReviewedKubernetesBeginner3 minFreegit push rejected (fetch first): a push that worked 30 minutes agogit push rejected (fetch first): a push that worked 30 minutes ago is a hands-on troubleshooting drill. Know what 'fetch first' means and why --force is the wrong fix. repository-access needs to be checked by narrowing scope, recent change, and the current live signal before r...ReviewedCI/CDBeginner3 minFreePending: new pods do not start after scaling outPending: new pods do not start (Resource Exhaustion) is a hands-on troubleshooting drill. Read a FailedScheduling event to see why a pod cannot be placed. Kubernetes Scheduling and Capacity needs to be checked by narrowing scope, recent change, and the current live signal befo...ReviewedKubernetesBeginner3 minFreeActions fails only on fork PRs: Username and password requiredActions fails only on fork PRs: Username and password required is a hands-on troubleshooting drill. Know why repository secrets are not passed to pull requests from forks. pull-request-security needs to be checked by narrowing scope, recent change, and the current live signal...ReviewedCI/CDBeginner3 minFreeCICD-009Deployment failingA scenario that narrows down the root cause, centered on checking the permission-policy difference by event type, in the situation of a deployment failing because the secret is empty only on tag releases.ReviewedCI/CDIntermediate21 minFreeSECURITY-056Secrets Manager rotation updates the writer credential but read replicas still use the old secretRotation completes successfully on the primary path, yet one read-side workload keeps failing because its secret retrieval or cache path was never included in the rotation design.ReviewedSecurityIntermediate21 minFreeCICD-001Finding the real failure point in GitHub Actions build logsA training scenario for isolating the true cause from logs where npm dependency conflicts and cache traces are mixed together.ReviewedCI/CDIntermediate20 minFreeK8S-011A readiness probe path typo keeps the rolling update from finishingA readiness probe path typo keeps the rolling update from finishing is a hands-on troubleshooting drill. A situation where the application is fine but only the probe path is wrong, so new Pods never become ready. Kubernetes Config and Rollouts needs to be checked by narrowing...ReviewedKubernetesBeginner16 minFreeCICD-007Builds failingA scenario that narrows down the root cause, centered on realigning the cache key strategy and lockfile consistency, in the situation of builds failing because the cache key gets tangled after a Node version upgrade.ReviewedCI/CDBeginner16 minFreeCICD-021Build cache key mismatch after lockfile updateA pipeline stays green on one branch and fails on another because the dependency cache key no longer matches the lockfile layout.ReviewedCI/CDBeginner17 minFreeA node goes NotReady after a rebootAfter an OS security update and reboot, one node stays NotReady. SSH works, but kubelet keeps failing to start.ReviewedKubernetesIntermediate16 minFreePods get Evicted in bulkDozens of pods on two nodes show Evicted. The nodes report DiskPressure and one container is using 18Gi of ephemeral storage after debug logging was left on.ReviewedKubernetesIntermediate18 minFreedocker push: denied: requested access to the resource is denieddocker push: denied: requested access to the resource is denied is a hands-on troubleshooting drill. Check which registry an image tag actually points to before debugging credentials. GitHub Container Image Delivery needs to be checked by narrowing scope, recent change, and th...ReviewedCI/CDBeginner14 minFreeOOMKilled: a container keeps restarting after hitting its memory limitOOMKilled: a container keeps restarting (CrashLoop and Restarts) is a hands-on troubleshooting drill. Read OOMKilled and exit code 137, then fix memory limits and the workload that exceeds them. kubernetes-workload-reliability needs to be checked by narrowing scope, recent cha...ReviewedKubernetesBeginner15 minFreeK8S-012The init container finished, but the main container cannot see the config fileA situation where the initialization step succeeded but the volume mount location differs, so only the runtime container fails.KubernetesIntermediate20 minFreeK8S-016After changing the Deployment selector, the ReplicaSet cannot grab the new PodsAfter changing the Deployment selector, the ReplicaSet cannot grab the new... is a hands-on troubleshooting drill. An introductory problem for understanding selector immutability and label strategy in declarative resources. Kubernetes Config and Rollouts needs to be checked by...KubernetesBeginner15 minFreeCICD-018A path-filter malfunction that drops tests only on pull request eventsA path-filter malfunction that drops tests only on pull request events is a hands-on troubleshooting drill. Covers a problem where a wrong changed-file path filter drops the most important PR tests. Container Image Delivery needs to be checked by narrowing scope, recent change...CI/CDBeginner16 minFree