Felis/docs/troubleshooting.md

Felis Troubleshooting Checklist

This file is the spec §28 #23 deliverable: a故障排查清单 (troubleshooting checklist) for the failure modes the platform actually produces. Every symptom below is traced to a concrete signal — a status.conditions reason, an HTTP error code, a log string, or a manifest name — so an operator can map what they see to the code path that emitted it.

How to read this document

Each entry is symptom → likely cause → where to look → fix. Signals are graded for how far the in-repo Go test suite proves the behaviour:

• [GO-TESTED] — a hermetic *_test.go exercises this exact path; the string/code is asserted in CI.
• [PG-TESTED] — a -tags pgint test in internal/pgint drives it against a real Postgres with the shipped migrations (CONTRIBUTING.md has the command).
• [CODE-ONLY] — the code path and string exist and are real, but no unit test drives them (notably the Velocity Java plugin, which is not compiled or tested in this repo).
• [INTEGRATION-ONLY] — the symptom is produced by the kubelet, kaniko, containerd, Postgres, or the network, not by Felis Go code; you will see it in kubectl describe / pod logs, never in MinecraftServer.status.
• [INERT] — the configuration field exists in the CRD but no controller reads it. Tuning it does nothing. No CRD field carries this status today; the last one, spec.storage.retainOnDelete, was removed rather than implemented (§13 records why). A field whose change seems ignored is almost always a condition instead — §12 lists the fields that are read and the condition each depends on.

The operator never invents the parent domain; routing identity is spec.subdomain under the deployment zone. Examples below use <root-domain> / registry.<ns>.svc:<port> placeholders rather than any concrete host.

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1. Server is stuck in Starting and never becomes Running

MinecraftServer.status.phase stays Starting. A start that never succeeds is requeued every 5s until one of the two startup budgets expires, then escalated to Failed — StartupTimeout if the pod never passed TCP readiness, ReadinessTimeout if the RCON probe never succeeded. Both default to 300s when spec.startup.timeoutSeconds / spec.startup.readinessTimeoutSeconds are unset or 0, and both are measured from status.startRequestedAt. [GO-TESTED: TestReconcileRunning_StartupTimeoutConvertsToFailed, TestReconcileRunning_ReadinessTimeoutConvertsToFailed.]

So Starting seen once is normal and TestReconcileRunning_RconProbeFailureStaysStarting asserts exactly that — a single failed probe must not flap the phase. Starting seen for longer than the budget means the reconcile loop is not running at all; check the operator's own logs before tuning anything. Either way the underlying cause is diagnosed from pod state, not from MinecraftServer.status.

First, read the condition reason:

kubectl get minecraftserver <name> -o jsonpath='{.status.conditions}'

markStarting writes the same reason to both Ready=False and RconReached=False. The reason is exactly one of:

status.conditions[].reason	Meaning	Requeue
PodNotReady	Pod not TCP-ready yet (status.readyReplicas < 1)	5s
RconSecretUnavailable	RCON secret missing or malformed	10s
RconNotReachable	RCON dial/auth failed	5s

[GO-TESTED for the reason set.]

1a. PodNotReady — pod never goes ready

The operator cannot tell why the pod is not ready; a broken image, an unbound PVC, and a backend that simply has not finished booting all surface as the identical PodNotReady signal. [GO-TESTED that the reason is emitted; [INTEGRATION-ONLY] for the underlying pod cause.] You must drop to the pod:

kubectl get pod -l app.kubernetes.io/name=<name>
kubectl describe pod <pod>     # look at Events + container State

• ImagePullBackOff / ErrImagePull → spec.image is wrong, the tag does not exist, or the registry is unreachable. spec.image is copied verbatim into the container with zero validation by the operator. Fix the image reference, or see §7 (registry reachability) and §6 (build push target).
• PVC Pending → kubectl get pvc -l app.kubernetes.io/name=<name>. A nonexistent spec.storage.storageClassName, or a request larger than any class can satisfy, leaves the PVC unbound. The operator does not error on this (only a malformed quantity errors — §2); it waits in Starting indefinitely. Fix the StorageClass name or capacity. [INTEGRATION-ONLY.]
• Container crash-looping before the readiness port opens → check container logs; this is a backend/entrypoint problem, not a Felis problem.
• Stuck in Init: or AccessDeniedException / Permission denied in the log → the pod runs as uid/gid 1000 (naming.GameUID) with every capability dropped, whatever USER the image declares. Before the server starts, the prepare-data initContainer (felis init-volume, root with only CHOWN + DAC_OVERRIDE) hands every world entry not yet owned by 1000:1000 to that uid, so a world written by an older root-run release or extracted by a restore Job is fixed on its next start: kubectl logs <pod> -c prepare-data prints how many entries it changed and lists up to 20 it could not. An image that writes outside /data and /tmp (a directory baked into the image as root) cannot run as uid 1000; rebuild it to keep its state under /data. [GO-TESTED: TestBuildStatefulSetRunsGameAsNonRoot, TestChownTreeHandsOverMismatchedEntries; INTEGRATION-ONLY for the walk on a live volume.]
• FailedCreate … violates PodSecurity "baseline" on the StatefulSet or a Job → the minecraft namespace enforces the PodSecurity baseline profile (pod-security.kubernetes.io/enforce=baseline, set by the install bundle). Everything Felis renders there fits it; a pod that is refused was edited or created outside Felis (hostPath, hostPort, privileged, extra capabilities). kubectl get events -n minecraft --field-selector reason=FailedCreate names the field. [GO-TESTED: TestObjects_MinecraftNamespaceEnforcesBaseline.]

1b. RconSecretUnavailable — RCON secret missing or malformed

The probe needs the RCON password from spec.rcon.secretRef. The message is the verbatim error: [CODE-ONLY for these branches]

• rcon.secretRef.name and .key are required when rcon is enabled — you enabled spec.rcon.enabled but left secretRef.name or secretRef.key empty.
• secret "<name>" has no key "<key>" — the Secret exists but lacks the named key.

Fix: create the Secret with the referenced key, or correct secretRef. Verify:

kubectl get secret <secretRef.name> -o jsonpath='{.data.<key>}' | base64 -d | wc -c

1c. RconNotReachable — RCON dial or auth failed

The probe is a TCP connect plus RCON auth handshake, then immediate close — no command is ever run; a successful auth IS the entire readiness gate. The message is the verbatim dial error:

• rcon: authentication failed → the password in the Secret does not match the backend's rcon.password. Reconcile the two. [GO-TESTED that this maps to RconNotReachable.]
• connection refused / i/o timeout → the backend has not opened the RCON port yet, RCON is disabled in server.properties, or spec.rcon.port (default 25575) is wrong. [INTEGRATION-ONLY for the live handshake.]

The per-probe timeout is a fixed 5s in code (prober.go:45, shortened further if the reconcile context has a nearer deadline). It is not derived from spec.startup.readinessTimeoutSeconds, which is the deadline for the whole start, not for one probe — see §12.

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2. Server is in Failed

There is exactly one path to PhaseFailed: markFailed(server, "InvalidSpec", err), reached only when the StatefulSet cannot be built. In practice this means a malformed spec.storage.size (an unparseable resource quantity), surfaced as:

invalid storage size "<value>": <parse error>

status.conditions will show Ready=False and Provisioned=False, both with reason InvalidSpec. Fix the quantity (e.g. 10Gi, not 10 GB) and the server leaves Failed on the next reconcile. [GO path is real; the specific branch is [CODE-ONLY] — the reconciler test fixture uses a valid size.]

Two caveats when a server has been in Failed:

• A pod-not-ready or unreachable-RCON server is never Failed; it is Starting (§1). If you see Failed, it is a spec problem, not a runtime one.
• markFailed does not reset status.endpoint. A server that fails after having been Running keeps a stale endpoint.mode=direct. The proxy should treat any non-Running phase as "do not route direct" rather than trusting a lingering direct endpoint (§4).

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3. Players can't join / get sent to the wrong place

Routing is driven by status.endpoint:

• markRunningReady is the only writer of endpoint.mode=direct (address=<game address>), and only while phase=Running and RCON-ready.
• markStarting, markStopping, markStopped all write endpoint.mode=fallback, address=spec.fallbackServer.

So the proxy should route direct only when phase=Running; otherwise it gets a fallback endpoint. [GO-TESTED for the direct/fallback toggle via markRunningReady/markStopped.]

Two pitfalls:

1. spec.fallbackServer is empty → the fallback endpoint address is "", so during Starting/Stopping/Stopped the proxy has no lobby to park the player in. Set spec.fallbackServer to a registered Velocity server name.
2. Stale direct after Failed → see §2; the proxy must not honour a direct endpoint unless phase=Running.

3a. Wake-on-join is refused, slow, or rate-limited

When a player joins a stopped server, the proxy parks them in the fallback and calls the internal wake API. The authorization gate order is autostartPolicy → per-server cooldown → global running cap. Map the API result:

HTTP	Code	Cause	Fix
403	forbidden	autostartPolicy=allowlist and UUID not allowlisted, or ownerOnly and caller is not owner	Add the UUID / claim the server / set autostartPolicy=public
409	maintenance_in_progress	A restore, backup or file write holds the server's world volume (§3b)	Wait for the Job to finish
429	(cooldown)	Wake retried within the 30s per-server WakeCooldown	Wait out the cooldown
503	at_capacity	Global MaxRunningServers cap reached	Stop another server or raise the cap

[GO-TESTED: handlers_internal_wake_test.go, cooldown, running-cap shape.] The operator's RCON probe — not the wake call — is the authoritative readiness gate; the proxy polls GET /api/v1/internal/servers/{name}/status every ~2s and teleports when ready=true.

The Velocity-side consumption of these codes (403 → "You're not allowed to start «server»"; 409 maintenance_in_progress → "«server» is under maintenance", not queued; 429 → re-queue; other → "Couldn't start … Try again shortly.") lives in the Java plugin and is [CODE-ONLY] — the codes it reacts to are produced by the Go-tested authorizeWakeByUUID / cooldown limiter, so grade the two halves separately.

3b. Wake, restore, backup or file save refused with maintenance_in_progress

A server's world volume is ReadWriteOnce, and on a single node RWO lets a game pod and a restore Job mount it side by side. So felis-api serialises them per server: a restore, a backup, or a file write takes the world, and until its Job finishes every wake (panel or join) and every other world operation on that server gets 409 maintenance_in_progress. File reads and listings never hold it. The operator applies the same rule when desiredState is flipped to Running by anything other than felis-api: the StatefulSet is not scaled up, and the Ready condition reads MaintenanceInProgress until the Job ends.

What holds the world, in order:

1. An unfinished Job labelled felis.lolicon.best/server=<name> with app.kubernetes.io/managed-by felis-restore, felis-backup, or felis-files plus felis.lolicon.best/files-mode=write:

   kubectl -n minecraft get jobs -l felis.lolicon.best/server=<name>
   

   A Job that is genuinely wedged is ended by its own activeDeadlineSeconds; deleting it by hand releases the world at once (kubectl -n minecraft delete job <job>), at the cost of whatever it was writing.

2. The admission lock felis.lolicon.best/maintenance=<kind>@<RFC3339> on the MinecraftServer. felis-api sets it for the milliseconds between admitting an operation and creating its Job; it holds for at most two minutes if felis-api died in between, and the next wake clears a stale one. To drop it by hand:

   kubectl -n minecraft annotate minecraftserver <name> felis.lolicon.best/maintenance-
   

A restore, backup or file write refused with 409 not_stopped although the panel shows Stopped means the game pod is still terminating (its shutdown save can take a while); retry once kubectl -n minecraft get pods -l felis.lolicon.best/server=<name> shows nothing.

[GO-TESTED: internal/maintenance, k8scluster_maintenance_test.go, handlers_maintenance_test.go, operator maintenance_test.go.]

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4. Routing is disabled even though servers are up (online-mode coupling)

Wake/claim/allowlist semantics trust Mojang-verified online-mode UUIDs. If the proxy runs online-mode=false, those identities are spoofable, so the Velocity plugin refuses to activate routing:

Felis routing DISABLED: the proxy is in offline mode (online-mode=false).
Domain autostart and the allowlist trust Mojang-verified UUIDs; refusing to
route on spoofable identities. /link remains available. Set online-mode=true to
enable routing.

[CODE-ONLY — FelisVelocityPlugin.onProxyInitialize.] /link still works (account binding does not depend on routing), but no domain autostart happens. The summary line prints routing: disabled (offline mode) or (no root-domain set). Fix: set online-mode=true on the proxy, or configure the root domain if the log says no root-domain set.

On the server side, spec.autostartPolicy and spec.onlineMode are documented as only meaningful when the proxy enforces online-mode=true. Setting them does not by itself make an offline proxy safe — the proxy guard is the enforcement point.

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5. Web panel returns 401 / 403 (Zero-Trust / Cloudflare Access)

The external face accepts either a Cloudflare Access JWT (Cf-Access-Jwt-Assertion header) or a local session cookie. The error envelope is always {"error":{"code","message","request_id"}}. [GO-TESTED.]

• 401 unauthorized — not authenticated: no/invalid Access JWT and no valid session. [GO-TESTED.]
• 403 forbidden — authenticated but not permitted (e.g. a non-admin principal hitting an admin route; IsAdmin() requires role=admin and arrival via the admin Access audience/host). [GO-TESTED.]

5a. Every external request 401s on a fresh deploy

The Access verifier is wired fail-closed: Keyfunc (the JWKS key function) is nil until deployment wiring supplies it. With a nil Keyfunc, every JWT verification fails, and startup logs:

felis api: external face fails closed (Access JWKS key function not configured)

[INTEGRATION-ONLY — the live JWKS path is a deployment point.] This is intended: the panel rejects all callers until JWKS is configured. Fix by wiring the Access JWKS key function for cfg.Auth.AccessJWTAud.

5b. Token rejected with audience error

token audience does not include "<aud>"

The JWT's aud claim does not contain the configured cfg.Auth.AccessJWTAud (or the admin audience for admin routes). [GO-TESTED.] Confirm the Access application audience matches cfg.Auth.AccessJWTAud.

Trust-model note for operators: verification is expiration-required + audience + signing-key (JWKS). There is no iss (issuer) check anywhere in the verifier. Trust rests entirely on the audience claim plus the JWKS signing key. When documenting or auditing the trust boundary, do not assume issuer is validated — it is not.

5c. Local-password login fails or is silently rejected

Local sessions use the felis_session cookie (HttpOnly, Secure, SameSite=Lax, 12h TTL, host-only). They are gated by the local_auth_enabled row in platform_settings, read live per request and fail-closed (missing or unparseable → treated as disabled). Symptoms:

• Cookie present but login rejected with local auth disabled → the local_auth_enabled setting is false/absent. A present cookie under disabled local-auth is rejected outright, not fallen through to the JWT path.
• invalid session: … → bad/forged session hash.

Fix: set local_auth_enabled=true in platform_settings if local password auth is intended. [GO-TESTED for the session/QR-login logic.]

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6. Internal API rejects Velocity / proxy callers (service-token)

The internal face (--internal-addr :8081, routes under /api/v1/internal/...) is never Zero-Trust; it authenticates a single service token via Authorization: Bearer <token>, compared in constant time.

In-cluster it is reached through the ClusterIP Service felis-api-internal (port 8081), which is separate from the external NodePort felis-api (443) precisely so the no-Zero-Trust face is never exposed on a node. On the control-plane node the break-glass console reaches it by resolving that Service's ClusterIP and dialing :8081.

• Internal calls fail to connect (not 401) → the felis-api-internal Service is missing or its selector no longer matches the api pods. kubectl -n felis get svc felis-api-internal must show a ClusterIP with 8081; a bare felis-api name serves only 443 and every internal call would hang/refuse.

• All internal calls 401 → the token is unset or wrong. The API reads env FELIS_SERVICE_TOKEN. If unset, startup logs:

  felis api: warning: FELIS_SERVICE_TOKEN unset — internal face will reject all callers
  

  and wires an empty token, which rejects everyone (no bypass). [GO-TESTED for the constant-time compare / empty-token rejection.]

In-cluster, the token's source of truth is the Secret felis-service-token (key token), injected as FELIS_SERVICE_TOKEN on the API Deployment. Fix:

kubectl get secret felis-service-token -o jsonpath='{.data.token}' | base64 -d

Ensure the proxy is configured with the identical value.

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7. Account-link and claim API errors

Codes from handlers_account.go / handlers_internal.go. [GO-TESTED.]

HTTP	Code	When
400	bad_request	Missing mc_uuid, empty code, or invalid auth_source (must be mojang/thirdparty)
400	invalid_code	Link code unknown or expired (10-min TTL, 8-symbol code)
409	already_linked	That MC UUID is already linked to another user
412	not_linked	Claim/owner op by a caller with no verified account link
403	quota_exceeded	Claim would exceed the user's server quota
409	already_claimed	Atomic UPDATE … WHERE owner_id IS NULL affected 0 rows
404	not_found	Unknown server/resource

Flow reminder: the code is minted in-game on the internal face (POST /api/v1/internal/account/link/code, proves the UUID) and verified on the web external face (POST /api/v1/account/link/verify, proves the user). A 409 already_linked rolls the transaction back and preserves the code so a different user can still use it. The claim's race-safety is the single conditional UPDATE under READ COMMITTED — 1 row → 200, 0 rows → 409. The real SQL execution is [INTEGRATION-ONLY] (no sqlmock/dockertest in repo); the handler logic is [GO-TESTED] via an in-memory fake repo.

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8. Image build fails (Kaniko, spec §14/§16)

8a. Build push rejected at submission with 400

Pre-build validation rejects any push target that is not the internal registry:

must target the internal registry "<registry.<ns>.svc:<port>>", not "<your-target>"

[GO-TESTED via the validate gate.] Fix the image reference to push to cfg.Registry.URL (the internal registry — §9).

8b. Build Job's ServiceAccount can do nothing (RBAC "denial" by design)

The build/restore Job SAs (felis-build, felis-restore, namespace felis-build) have no Role and no RoleBinding anywhere — isolation is the absence of permissions (spec §16/§21). If you see the build SA denied a namespaced API operation, that is correct, not a misconfiguration. [GO-TESTED that the rendered manifests give these SAs no Role.] Do not "fix" it by granting the build SA permissions.

8c. Build hangs then fails fetching base image / packages

The build namespace runs a default-deny egress NetworkPolicy (felis-build-egress); the only allowed egress is the package-mirror CIDRs from --package-cidr, which defaults to none (fail-closed, no internet). [GO-TESTED for the netpol shape.] A kaniko run that hangs pulling a base image or OS package from a non-allowlisted host is the egress policy doing its job — the hang/failure text comes from kaniko/containerd and is [INTEGRATION-ONLY]. Fix: add the mirror CIDR via --package-cidr, or pre-stage the base image in the internal registry.

8d. Build reaches Failed phase

reconcileBuilds polls the Job; a Job reaching Failed is surfaced via writeBuildError (JobPhase→Failed). [GO-TESTED for the mapping.] The underlying cause — a kaniko build error, the Trivy CRITICAL-CVE gate failing the build (spec §16), or the final push — is in the Job's pod logs and is [INTEGRATION-ONLY]. The pod runs egress-gate (§8f), context-fetch, kaniko (builds a tarball, never pushes) and trivy (scans that tarball) as init containers, then push — so a CVE-rejected image never reaches the registry. Inspect every step:

kubectl logs -n felis-build job/<build-job> --all-containers --prefix

A push that fails with 403 means the target repository is under felis/ or mirror/ — the registry gate reserves those for the platform (§9); 401 means the felis-registry-push Secret in felis-build is missing or stale (re-run the installer).

8e. Build Pods never start: executor images and air-gapped installs

The build Job runs Kaniko and Trivy from external registries by default (gcr.io/kaniko-project/executor:latest, aquasec/trivy:latest). On a box whose build namespace cannot reach those registries (the egress policy allows only DNS, the internal registry and --package-cidr mirrors — and an air-gapped box has no route at all), the Pods sit in ImagePullBackOff/ErrImagePull and the build stays building until its deadline. Point the overrides at images in the internal registry — the one pull source that survives an image GC (a bare node-containerd import does not: kubelet's image GC collects unused images under disk pressure, and an air-gapped box then has nothing to restore them from) — in felis.toml:

[registry]
url = "registry.felis.svc:5000"
build_namespace = "felis-build"
kaniko_image = "registry.felis.svc:5000/mirror/kaniko-executor:v1.24.0"
trivy_image  = "registry.felis.svc:5000/mirror/trivy:0.74.0"
trivy_db_repository = "registry.felis.svc:5000/mirror/trivy-db:2"
trivy_java_db_repository = "registry.felis.svc:5000/mirror/trivy-java-db:1"
build_cpu_limit = "2"
build_mem_limit = "4Gi"
build_disk_limit = "12Gi"          # §8f
build_user_namespaces = "auto"     # §8f: auto | on | off
build_runtime_class = ""           # §8f: e.g. "gvisor"
max_concurrent_builds = 2          # §8f: 1-6; later builds queue

Mirror the executor images into the registry once. On the node itself, push through the loopback hostPort the registry Deployment binds (docker treats 127.0.0.1 as insecure by default; the installer leaves the daemon stopped, so sudo systemctl start docker first). The registry takes writes only from an authenticated principal, and mirror/ only from platform, so log in with the platform token first:

kubectl -n felis get secret felis-registry-auth -o jsonpath='{.data.platform}' | base64 -d \
  | docker login --username platform --password-stdin 127.0.0.1:5000
docker pull gcr.io/kaniko-project/executor:v1.24.0   # any versions you pin
docker pull aquasec/trivy:0.74.0
docker pull mirror.gcr.io/aquasec/trivy-java-db:1
docker tag gcr.io/kaniko-project/executor:v1.24.0 127.0.0.1:5000/mirror/kaniko-executor:v1.24.0
docker tag aquasec/trivy:0.74.0                   127.0.0.1:5000/mirror/trivy:0.74.0
docker tag mirror.gcr.io/aquasec/trivy-java-db:1  127.0.0.1:5000/mirror/trivy-java-db:1
docker push 127.0.0.1:5000/mirror/kaniko-executor:v1.24.0
docker push 127.0.0.1:5000/mirror/trivy:0.74.0
docker push 127.0.0.1:5000/mirror/trivy-java-db:1
docker logout 127.0.0.1:5000

From another machine, port-forward the registry instead (kubectl -n felis port-forward svc/registry 5000:5000) and push to localhost:5000/... — the registry keys a repository by the path after the host, so pushes through either door land in the same place the build Pods will pull from.

Put them in both /etc/felis/felis.host.toml (host-side CLI) and /etc/felis/felis.pod.toml (the file rendered into the API's felis-config Secret — the two differ only in the database URL; the setup screens re-render the Secret from the pod file, so edits made only through kubectl on the live Secret are lost at the next reconfigure). A Deployment restart alone is NOT enough — the API Pod mounts the Secret, never the host file. Re-render the Secret from the pod file, then roll felis-api:

kubectl -n felis create secret generic felis-config \
  --from-file=felis.toml=/etc/felis/felis.pod.toml --dry-run=client -o yaml | kubectl apply -f -
kubectl -n felis rollout restart deployment/felis-api

Unset fields keep the defaults.

trivy_db_repository is not optional on an egress-locked box. Trivy fetches its vulnerability DB from mirror.gcr.io/ghcr.io unless told otherwise, and the build egress policy denies those hosts — so the scan step fails closed (failed to download vulnerability DB), nothing is pushed, and NO build ever completes. Mirror the DB into the internal registry once:

# On the node (docker treats 127.0.0.1 as insecure by default), or through the
# port-forward above, logged in as platform (see the block above):
#   docker pull mirror.gcr.io/aquasec/trivy-db:2
#   docker tag  mirror.gcr.io/aquasec/trivy-db:2 127.0.0.1:5000/mirror/trivy-db:2
#   docker push 127.0.0.1:5000/mirror/trivy-db:2

The Job's Trivy container runs with --insecure, so the internal registry's plain HTTP works for the DB pull; reads need no credential. Re-mirror the tag periodically (Trivy refreshes the DB several times a day upstream; a stale mirror only means stale CVE data, never a failed gate).

trivy_java_db_repository is the same story one step lazier: Trivy downloads the Java DB on demand the first time it scans an image containing Java artifacts — every real modpack — and that download fails closed too. Mirror mirror.gcr.io/aquasec/trivy-java-db:1 alongside the vulnerability DB (commands above); the Java DB refreshes far less often than the vulnerability DB, so a one-off mirror is usually fine.

8f. Build isolation model and residual risk

A Dockerfile's RUN steps execute inside the kaniko container, as root. Kaniko is a daemonless image builder; it is not a sandbox. What stands between an approved-but-hostile Dockerfile and the node is the pod around it:

Layer	What it does	Where
Admin approval	Nothing builds until an administrator approves the submission	submit lane
Reviewed bytes	the approval names the context's sha256; a re-upload after review fails the approval, and the build refuses any other bytes	submit lane, felis fetch-context
Weak identity	felis-build SA, no Role anywhere, no token mounted	§8b
Egress lock	felis-build-egress: cluster DNS, the registry, the api internal face, nothing else	§8c
Egress gate	first init container; holds the pod until the lock is enforced for it	felis egress-gate
Capabilities	every container drops ALL; kaniko gets back only CHOWN, DAC_OVERRIDE, FOWNER to unpack base images	jobspec
seccomp	the whole pod runs under the runtime's default profile (no unshare, mount, keyctl, bpf, …)	jobspec
User namespace	with build_user_namespaces on, root in the pod is an unprivileged uid on the node	below
Sandbox runtime	optional build_runtime_class (gVisor, Kata)	below
Credentials	the registry credential lives only in the push container; the service token only in context-fetch	jobspec
Resources	CPU, memory and ephemeral-storage limits per container; activeDeadlineSeconds; the context extraction stops at 4 GiB or 200 000 entries	jobspec, felis fetch-context
Namespace backstop	felis-build-limits LimitRange gives any container without limits 1 CPU / 1 GiB / 1 GiB disk; felis-build-quota allows 8 running pods and no PVCs	bundle
Concurrency	at most [registry] max_concurrent_builds (default 2, at most 6) builds run; later ones wait as pending (Queued) and start oldest first	build.Builder

Reviewed bytes. Every upload records the sha256 of the archive, and the review page shows it. The context download carries the same value in the X-Felis-Context-Sha256 header; the API cuts the transfer off if the stored bytes no longer match it. Approving sends that digest back as expected_digest, and the approval fails with 409 context_changed when the submitter has uploaded again since: download and review the new upload. The approved digest is pinned on the build, and felis fetch-context --sha256 hashes every byte it receives; a mismatch fails the build before Kaniko starts:

felis fetch-context: the context's sha256 is 3f…, the approved digest is 9a…: it changed after approval; refusing to build

The panel approves with the digest of the file it downloaded in the same session. When the review happened elsewhere (a CLI download, another browser), it approves with the digest the list shows, so compare that value with sha256sum of the file you actually read. A submission uploaded before digests were recorded cannot be approved until the submitter uploads it again.

Egress gate. The CNI programs a new pod's NetworkPolicy a moment after the pod starts. On k3s (kube-router), a pod in felis-build could reach the internet and the Kubernetes API for its first ~0.7 s. egress-gate dials the Kubernetes API Service, which the build policy never admits, and exits once it stops answering. The build pod log shows the wait:

felis egress-gate: 10.43.0.1:443 is unreachable after 612ms (...); the egress lock is in effect

If the probe still answers after two minutes the gate exits 1 and the build fails: the build namespace's NetworkPolicy is not enforced. The cluster is running without NetworkPolicy enforcement (a CNI without it, or k3s started with --disable-network-policy); fix the cluster, not the gate.

User namespaces (build_user_namespaces). With hostUsers: false, uid 0 in the build pod maps to an unprivileged uid range on the node, so a container escape lands as nobody. It needs Kubernetes ≥ 1.33, containerd 2.x, and a kernel with idmapped mounts on the node filesystem (5.19+ upstream; the RHEL/CentOS Stream 9 kernels carry the backport). auto, the default, lets felis-api decide at startup: it runs one userns-probe-* Job in felis-build and turns the feature on only when that pod ran. The api log says which way it went:

felis api: build pods run in a user namespace (hostUsers: false)
felis api: build pods run without a user namespace: this node cannot start a pod with hostUsers: false

on forces it (builds then fail to start on a node that cannot do it), off never uses it.

Sandbox runtime (build_runtime_class). Naming a RuntimeClass runs build pods under it, for example gVisor (runsc) or Kata. The class must exist (kubectl get runtimeclass), and kaniko must work under it: gVisor needs its default overlay2 rootfs, and Kata needs nested virtualization on a VM node. Leave it empty unless you have installed and tested one.

Disk (build_disk_limit, default 12Gi). This caps kaniko's writable layer (the unpacked base image) and, as the largest limit in the pod, the pod's total disk: extracted context, unpacked base image and image tarball together. The kubelet enforces it by eviction on its housekeeping sweep, so a build that runs past it is killed within seconds. The build then fails with Evicted in kubectl -n felis-build describe pod. Raise it for very large modpacks, and keep the node's free disk above it.

Residual risk. Without a user namespace or a sandbox runtime, the build runs as root in a container on the same kernel as the game servers and the control plane. Seccomp and the dropped capabilities remove the common escape primitives. A kernel vulnerability reachable through the remaining syscalls still reaches the node, and on a single-node install the node is the whole platform. Admin approval is the control that remains: read the Dockerfile and download the context before approving. On a node where the probe comes back negative, a kernel upgrade that brings idmapped mounts is the cheapest hardening available.

---

9. Registry push/pull failures (spec §15)

The in-cluster registry is Deployment/Service/PVC named registry in the control namespace (or --registry-namespace):

• Push/pull target (the exact string to match): registry.<ns>.svc:<port> (port from --registry-port, default 5000; e.g. --felis-image registry.felis.svc:5000/felis:v1). A wrong push URL is caught at build time by the validate gate (§8a, 400). An unreachable registry at runtime (wrong DNS/port, PVC unbound, missing default StorageClass) surfaces as kaniko push or kubelet pull errors — [INTEGRATION-ONLY], not a Felis-emitted string.
• Storage: PVC is RWO, 10Gi, mounted at /var/lib/registry, no storageClassName → binds the cluster default class. If the cluster has no default StorageClass the PVC stays Pending and the registry never starts.
• Node-side pulls: containerd cannot dial the Service VIP (the live stack answered "Empty reply"), so the registry Deployment binds a loopback hostPort (127.0.0.1:<port>) and the installer writes a /etc/rancher/k3s/registries.yaml mirror relaying registry.<ns>.svc:<port> onto it. That pair is what lets kubelet re-pull a garbage-collected image; both halves must survive together (remove either and every pull after an image GC fails).
• Memory: the registry's limit is 2Gi, deliberately larger than the other control-plane pods' 256Mi — a live 475MB-layer push OOM-killed the 256Mi template mid-upload (audit #46). Very large layers need headroom here, not more CPU.
• Write authorization: registry:2 listens on the pod's loopback only; the registry-gate sidecar (felis registry-gate, the felis image) owns the port and the hostPort. Reads are anonymous — containerd, Kaniko and Trivy pull without a credential — but an anonymous GET /v2/ answers 401 Basic so docker knows to send the credential on a push. Every write needs HTTP basic auth against a token in the felis-registry-auth Secret: platform may write anything (the installer's own images, the mirror/ DB copies); build (a build Job's push container, via felis-registry-push in felis-build) may write anything outside felis/ and mirror/ and may never delete. A missing Secret leaves the registry read-only rather than down. The tokens persist in /etc/felis/secrets.env; rotating one means editing it there and re-running the installer, then kubectl -n felis rollout restart deployment/registry (the gate reads its tokens at start).
• Who can connect: felis-registry-ingress admits only the felis-build namespace to the registry pod. Node-local traffic (containerd pulls, the installer's pushes through the hostPort) is always allowed by Kubernetes; game servers cannot reach it at all (felis-server-egress).
• GC pinning: the registry pod's own images (registry:2 and the felis image its gate runs) cannot be pulled from the registry they make up, so the installer labels both io.cri-containerd.pinned=pinned in containerd and kubelet's image GC never collects them. Check with k3s ctr images ls | grep pinned.
• Selector quirk worth knowing: the registry Service selector is only name + component=registry — it deliberately lacks the part-of=felis-control-plane label, so the registry is invisible to the RCON-peer NetworkPolicy selector. This is intended isolation, not a bug; do not "fix" it by adding the label.

Registry manifest rendering is [GO-TESTED]; actual serving is [CODE-ONLY/INTEGRATION-ONLY].

---

10. World reaper: false-deletes and skipped backups (spec §18)

The reaper is a run-once daily CronJob batch, not an operator controller. It reaps a world only when now - last_active_at > 15d (inactive_15d); the 15-day deadline is hard-fixed in code (only warn_before / retention / max_local_bytes and the on-demand backup keys manual_retention / manual_keep / manual_cooldown are configurable from felis.toml [archive]).

What a "backup" contains

A backup tars the server's ENTIRE data volume — the same volume the server mounts at /data: world folders, server.properties, plugins/mods, configs, jars, libraries, logs and cache, not just the world/ directory. A restore replaces the volume's contents with the archive (files added since the backup are pruned), so a restore also rolls config/plugin changes back. Sizes are dominated by libraries/cache on stock Paper servers (~170MB for a fresh instance before any world growth) — do not size the archive PVC as if only world data were stored.

The backup-before-delete invariant

The reap sequence (all [GO-TESTED] hermetically) preserves the world unless a confirmed, DB-recorded backup exists:

1. ensureCapacity (only if max_local_bytes > 0) frees room by evicting owners' on-demand backups first, oldest first, then reaper archives whose off-site copy is confirmed. The only copy of a reaped world is never evicted: it stays until retention expires it. Still full ⇒ world preserved (not deleted), counted in store_full=. [GO-TESTED: TestCapacityEvictionOrderSparesSoleCopies; PG-TESTED: TestManualBackupRationing]
2. Archiver.Archive fails ⇒ world preserved, PVC untouched.
3. InsertBackup (DB) fails ⇒ the orphan archive is deleted, PVC untouched.
4. With an [offsite] bucket configured (§16), the archive must also be in the bucket: until felis offsite sync has copied it and set offsite_at on its world_backups row, the run logs world archived, kept until the archive's off-site copy is confirmed, counts it in awaiting_offsite= and leaves the PVC alone. The next daily run after the copy reuses the same archive and deletes. [GO-TESTED: TestReapWaitsForOffsiteCopy]
5. Only then DeletePVC → ReleaseWorld → Stop (cosmetic) → audit → felis_reaper_worlds_deleted_total++.

So a missing backup never results in a deleted world, and with a bucket configured neither does a backup that exists on this disk only. [GO-TESTED: TestReapArchiveFailurePreservesWorld, TestReapInsertBackupFailurePreservesWorld, TestReapIdleWorldFullSequence.]

awaiting_offsite that stays above zero for more than a day means the copy is failing: sudo felis offsite status (§16).

A failed reaper Job

Each run ends with one line:

felis reaper: evaluated=12 reaped=1 awaiting_offsite=0 warned=2 skipped=0 store_full=0 evicted=0 expired=3 expire_failed=0

skipped counts servers the run failed on (steps 1–3 above, or the cluster or the database answering with an error; exempt servers and rows whose CRD is gone are not counted), store_full the subset kept because the backup store is full, and expire_failed expired backups it could not remove. Any of them above zero makes the process exit 1: the worlds are safe, but the Job fails so the watchdog mails world reaper Job … failed and FelisWorldJobFailed fires. The Job retries twice (backoffLimit), each retry re-running the whole batch, which is safe because every step is idempotent. Read the error above the summary:

kubectl -n minecraft logs job/<the failed felis-reaper-… Job>

A server that fails every day keeps its world and is retried every day, so the Job fails every day until the cause is fixed; after 26 hours the watchdog also reports the world reaper has not succeeded for …. [GO-TESTED: TestReportReaperRunFailsTheJob, TestExpiryFailureFailsTheRun, TestCapacityStillFullSkipsReap.]

On-demand backups ("Back up now")

An owner's "Back up now" writes a manual backup into the same store and onto the same disk as the worlds and the database, so it is rationed:

Key	Default	Effect
manual_retention	30d	when a manual backup expires (reaper archives use retention)
manual_keep	5	manual backups kept per server; after each backup the Job removes older ones and prints removed older backup …
manual_cooldown	10m	one owner-started backup per server per window; the next one gets 429 backup_cooldown with Retry-After (0s disables)

While the present backups add up to max_local_bytes or more, owners get 507 backup_store_full. Admins and the break-glass console are exempt from the cooldown and the cap. Whoever starts it, the backup Job refuses to write an archive that would leave less than 10% of the archive filesystem free: it fails with not enough free disk for the archive. A failed backup or restore shows the error its container exited on under Recent operations on the server's backup page. [GO-TESTED: TestBackupNow, TestCheckRoom, TestReaperConfigManualKeys, TestLatestJobsExplainsFailures]

Exemptions (world never reaped)

• spec.reaperExempt=true → skipped entirely (system servers). [GO-TESTED TestReapExemptServerNeverTouched.]
• CRD missing → logs reaper: CRD missing, skipping, skipped.
• Idle ≤ 15d → not yet eligible.

Pre-reap warnings (the warn_before offsets)

An OWNED server inside a warning window gets an email notice (3d/1d before the deadline, warn_before from [archive]) to the owner's verified email — the same [smtp] relay felis-api uses. The warned_3d_at / warned_1d_at stamps record a delivered notice:

• No [smtp] configured (or owner has no verified address): the run logs reaper: warning suppressed — no warner wired / a delivery error and does NOT stamp. Nothing is falsely recorded as sent, and the day SMTP is configured the pending warning can still go out.
• Delivery failure (relay down): logged and retried on the next daily run — bounded by the warning window, since the reap removes the candidate anyway.
• warned= in the run output counts DELIVERED notices, not attempts.

The reaper runs in the minecraft namespace and reads the mirrors of felis-smtp and felis-config there (a secretKeyRef is namespace-local). The installed felis setup's "configure email" screen refreshes both mirrors when it applies, so configuring SMTP after install is enough; a manual edit of the control-namespace Secret alone is not. [GO-TESTED: the delivered/retried/ suppressed matrix in internal/reaper; live-drilled end to end against a local SMTP sink.]

Genuine false-delete risk vectors

• Stale last_active_at. The keep-alive is RecordJoin, called from the internal join-event handler. If join events are not delivered to the API, the activity clock never resets and an actively-played world becomes reap-eligible after 15 days. Verify join events are flowing (§3a) — this is the most important reaper check. [INTEGRATION-ONLY for the live Postgres write.] A claim also resets it: ClaimServer sets last_active_at to the claim and clears warned_*, so a world reaped long ago and claimed again gets a full 15 days, and a later reap archives the new owner's world rather than reusing the previous owner's archive (FreshBackup counts only inactive_15d archives taken since the claim). [PG-TESTED TestReclaimRestartsReaperClock.]
• Unowned servers are still reaped. A server with owner_id="" gets no pre-deletion warning (maybeWarn skips unowned), but is still reaped at 15d. [GO-TESTED TestReapUnownedServerStillReaped.] Claim or exempt servers you want to keep.
• DeletePVC is idempotent (missing PVC is not an error), so a re-run will not fail on already-reaped worlds; and Stop failure is only logged, so a reaped world's MinecraftServer may not be flipped to Stopped.

Only TarLocal (tar+gzip) archiving is implemented; VolumeSnapshot/Longhorn backends return not implemented in this build. The live PVC delete / Postgres store paths are [INTEGRATION-ONLY].

Where worlds are read from (hostPath resolution)

The CronJob mounts --worlds-host-path read-only at /worlds through a static PersistentVolume (felis-worlds-root-<digest>, hostPath type Directory, Retain, pre-bound to the same-named PVC in the minecraft namespace), since the namespace's PodSecurity baseline refuses an inline hostPath in any pod. A re-install with a different worlds root or --reaper-node renders a new pair under a new digest; the old PV/PVC pair is left behind unused and can be deleted by hand (Retain: deleting it never touches the directory). The resolver runs cmd/felis/reaper.resolveWorldDir: it looks for <root>/<pvc>, then for the stock local-path directory <root>/<pv-name>_<ns>_<pvc-name> derived from the live PVC's spec.volumeName (never a glob — a leftover directory of a deleted PV must not stand in for the world the PVC currently binds). Pointing the flag at k3s's storage root (/var/lib/rancher/k3s/storage) is therefore the supported way to enable retention on a stock install. Two deployment facts the resolver cannot fix:

• Permissions. The reaper Pod runs as root and carries DAC_OVERRIDE: k3s's storage root is 0700 root:root, worlds are written by the game uid (1000) — or by root, for a world an older release wrote — and Paper saves level.dat mode-0600, so a fixed non-root identity (the previous uid-1000 convention, and the ACL setup that went with it) could neither walk the tree nor read the files — every archive failed open …/level.dat: permission denied. The installer no longer grants uid 1000 any access to the storage root: that uid is now the game servers'. If a world is still preserved while a reap was expected, it is a different cause: check the run's ERROR logs for the resolver's lstat messages before suspecting permissions.
• Node placement. Multi-node clusters: the world's directory exists only on the node holding its volume, so pass --reaper-node; it pins both the CronJob's pod and the PV (single-node starters are pinned implicitly).

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11. Idle auto-stop never fires; player count always shows 0

Every server created from the panel or felis apply stops itself after 600 s with nobody online (spec.idle), and the next join wakes it. An admin changes or turns it off under Edit server → Idle auto-stop. A server created before this default has no spec.idle and never stops; sudo felis converge gives it the default (§12b). The login gate and the lobby never idle out, whatever their spec says.

kubectl get minecraftserver <name> -o jsonpath='{.spec.idle}'

Both idle stop and the player count also hang off spec.rcon.enabled. Check it next.

kubectl get minecraftserver <name> -o jsonpath='{.spec.rcon.enabled}'

The player tally is a by-product of the RCON readiness probe: prober.go runs list on the same connection that just authenticated, and parseListReply reads the tally from the vanilla/Paper/Fabric/Forge reply (There are 3 of a max of 20 players online), the 1.12/Bukkit reply (There are 3/20 players online) or the EssentialsX reply (There are 3 out of maximum 20 players online, vanished players included), with § color codes stripped. With RCON disabled the probe never runs and no tally is ever read, so a permanent 0 means "never sampled", not "nobody online".

A tally that could not be read counts as unknown, never as zero. Idle auto-stop only acts on a count it actually read:

if players.Known && server.Spec.Idle.AutoStopEnabled && server.Spec.Idle.EmptySecondsBeforeStop > 0 {

An unknown tally leaves status.players at the last real count, neither starts nor clears the empty countdown, and sets the PlayersCounted condition to False with reason ListUnreadable. So enabling spec.idle.* without RCON is a no-op by design, and a server whose list reply is in a format Felis does not know (a plugin that rewrites /list, a translated reply) never idles out:

kubectl get minecraftserver <name> -o jsonpath='{.status.conditions[?(@.type=="PlayersCounted")]}'
# Reason ListUnreadable: run `list` in the server's panel console to see
# what the server actually answers.

Fix it by restoring a supported /list (for example, drop the plugin's override or its translation of that one message). The server keeps running either way; only the idle stop waits.

Both fields set and still nothing happens? Then the probe is failing rather than disabled: the server would be stuck in Starting with RconNotReachable (reconciler.go:156), which is §1's symptom, not this one.

This path used to fail even with everything configured correctly, through three stacked defects proven and fixed on a live cluster (auditfix21/22): the emptySince stamp was pruned by a missing CRD status field, a quiescent empty server produced no watch events to re-check the timer, and the Role lacked the minecraftservers:patch grant the stop write needs. If auto-stop ever looks dead again, check these three in order (each is now pinned by a test):

# ① The stamp must persist — should print a timestamp, not an empty string,
#    a few seconds after a server goes Ready with zero players.
kubectl get minecraftserver <name> -o jsonpath='{.status.emptySince}'

# ② The operator must be able to write spec.desiredState (403 in the operator
#    log = missing patch grant on Role felis-operator).
kubectl auth can-i patch minecraftservers -n <ns> --as=system:serviceaccount:<ctl-ns>:felis-operator

# ③ A wake-up must be scheduled: while empty, expect whatever you set
#    as emptySecondsBeforeStop to elapse and the box to flip to Stopped without
#    any external action.

While players are online the operator re-probes on a 30s cadence so it notices the moment the last one leaves; while empty it schedules a wake-up exactly at the deadline. Quiet operator logs on an idle server are normal — the action is the scheduled wake-up, not a stream of reconciles.

Note the reaper's last_active_at (§10) is a different subsystem (Postgres business layer, bumped by join events) — it keeps worlds alive against the reaper, but it does not auto-stop empty running servers.

---

12. A configuration field seems to be ignored

Every field below is read by a controller. What varies is the condition that decides whether setting it does anything.

Field	What you might expect	Reality
spec.startup.timeoutSeconds	Start budget before Failed	Read by startupTimedOut (reconciler.go:479), called at :126. 0 or unset falls back to 300s, then markFailed("StartupTimeout")
spec.startup.readinessTimeoutSeconds	First-probe budget	Read by readinessTimedOut (reconciler.go:490), called at :157. 0 or unset falls back to 300s, then markFailed("ReadinessTimeout"). Not to be confused with the prober's own 5s dial timeout (prober.go:45)
spec.idle.autoStopEnabled	Auto-stop empty servers	Read at reconciler.go:175 — but gated on spec.rcon.enabled, since the player tally comes from the RCON probe (§11)
spec.idle.emptySecondsBeforeStop	Empty grace period	Same branch. Must be > 0; the guard treats 0 as "off", not "stop immediately"

Both startup budgets are measured from the same status.startRequestedAt, so readinessTimeoutSeconds is not a budget after pod readiness — it is a deadline for the whole start, applied on the RCON-probe branch.

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12b. A newer field never reaches an already-installed system server (felis converge)

Provisioning is create-if-absent: felis setup never rewrites an existing login/lobby MinecraftServer beyond the config-derived env it owns, so a field the desired spec gained after your install sits absent forever — this is how a deployment ends up with a lobby that has no spec.rcon (a dead console and an online-player count that is always 0) and a login gate without spec.startup.healthHTTPPort. felis converge is the explicit pass that fills exactly those zero-valued fields (and re-adds a derived env key that is missing). It never overwrites a value that already holds one — an operator's RCON secretRef or tuning survives.

sudo felis converge

Run it after the images are in place. Enabling RCON, or the HTTP readiness gate, on a server whose image predates the listener would hold that server in Starting until the operator marks it Failed — that ordering is the reason this is a command you run rather than something setup does on every re-run. System servers that are already current report already converged.

The same pass gives every user server whose spec.idle was never set (one created before idle stop became the default) the default: stop after 600 s empty. A server whose idle stop an admin turned off keeps a duration on its spec (autoStopEnabled: false, emptySecondsBeforeStop set), so converge leaves it off; only servers it actually filled get a line.

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13. World PVC survives after I deleted the MinecraftServer

This is expected. The world PVC is a StatefulSet VolumeClaimTemplate. There is no persistentVolumeClaimRetentionPolicy and no finalizer anywhere in the operator. Deleting the MinecraftServer garbage-collects the StatefulSet, but StatefulSet deletion does not cascade to its template PVCs, and nothing else cleans them up. So the world PVC always survives server deletion. The only code that deletes a world PVC is the reaper, and only after a verified backup (§10). To reclaim a world PVC manually:

kubectl get pvc -l app.kubernetes.io/name=<name>
kubectl delete pvc <pvc>      # irreversible — the world is gone

spec.storage.retainOnDelete sat in the CRD and reached no controller. Spec v4.1 §5 asks for it — 「删除:finalizer 清 Service/STS/ConfigMap,PVC 按 retainOnDelete」 — and neither half was ever built: there is no finalizer, and nothing read the field. It was removed rather than implemented, which is a deliberate departure from that line, recorded here because the spec is a frozen document and still says otherwise.

The reasoning is that implementing it buys a second path that deletes a world — one that skips the reaper's verified-backup check — in order to restore a finalizer whose other listed duties (Service, StatefulSet, ConfigMap) ownerReference GC already performs. A CR still carrying the field keeps working: the API server prunes the unknown key on its next write, and nothing above changes, because retention was never conditional in the first place.

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13b. Node runs out of disk: what survives, and how to recover

A full disk is the most destructive failure this stack sees: kubelet evicts game pods (the control plane is protected below), and its image GC then collects images nothing is running. The images have a pull source now — the in-cluster registry — so they come back without an operator re-import; freeing space is what completes the recovery.

Eviction. Every control-plane pod (api, operator, reaper, registry) runs under the BUILT-IN system-cluster-critical PriorityClass (value 2e9). Kubelet's node-pressure eviction refuses to touch those pods — the log shows "Eviction manager: cannot evict a critical pod" for each of them — while game-server pods at the default priority 0 are evicted first. A drill that filled the disk to 1.7G free saw exactly this: login/lobby evicted, the whole control plane still Running (before the fix the same drill evicted the api, operator and registry too, and the image-GC stage below followed). User-defined PriorityClasses cannot substitute: the API caps them at 1e9, below kubelet's critical threshold. The built-in class allows preemption (its policy is fixed), so a control-plane pod that cannot fit may preempt a game pod — deliberate: the management plane must be placeable.

The pressure condition clears slowly. After you free space, the node can stay DiskPressure:True for up to ~5 minutes (--eviction-pressure-transition-period defaults to 5m, to stop the condition flapping); pods that need scheduling wait for it. This is the bulk of the "recovery takes minutes" observation, not a stuck node.

The images may be gone — they come back on their own. If pods were evicted, the kubelet can garbage-collect their images (unused > 2 minutes under imagefs pressure). Every image this platform runs is ALSO hosted in the in-cluster registry: the installer builds each one as registry.<ns>.svc:5000/felis/… and mirrors it there, and the node's containerd is configured (a registries.yaml mirror onto the registry's loopback hostPort) to relay those refs back through it. So a GC'd image is re-pulled on the next attempt with no operator action — delete the stuck pod to force an immediate retry (or wait out the backoff), and the workload converges.

If a pull does NOT come back:

1. Free disk on the node (df -h /var/lib/rancher; the biggest consumers are k3s ctr images ls -q and the world/backup PVCs under /var/lib/rancher/k3s/storage).
2. Check the registry: kubectl -n felis get pods -l app.kubernetes.io/component=registry and, on the node, curl -s -o /dev/null -w '%{http_code}\n' http://127.0.0.1:5000/healthz (expect 200: the registry gate answers it only while registry:2 behind it does). An anonymous GET /v2/ answers 401 by design — see §9.
3. Check the mirror file: /etc/rancher/k3s/registries.yaml must map registry.felis.svc:5000 to http://127.0.0.1:5000. Missing or changed: re-run the installer (it rewrites the file and restarts k3s only when the content changed).
4. Re-mirror a tag the registry does not have (hand-built images were never pushed): sudo systemctl start docker (the installer leaves the daemon stopped), log in as platform (§8e), then docker tag <ref> 127.0.0.1:5000/<repo>:<tag> && docker push 127.0.0.1:5000/<repo>:<tag>.

For an image that is in neither place, the old fallback still stands: re-run the installer (it rebuilds/re-imports from the local Docker store AND mirrors into the registry), or for a single image docker save felis:<tag> | k3s ctr images import -. The Docker store remains a deliberate second copy on the node; treat it as the recovery path, not as free space.

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14. Health alerts, and metrics for diagnosis (spec §23)

Every full install runs felis watchdog from felis-watchdog.timer, which mails the owners when something breaks, with no monitoring stack needed. The metrics and Prometheus rules below are for a deployment that also runs its own Prometheus.

The watchdog: what mails the owners

Every two minutes the host checks:

Check	Mailed after	Severity
felis-api, felis-operator or registry Deployment has no available pod (or is missing)	5 min	critical
Kubernetes API unreachable (k3s down): the cluster checks below are then unknown and keep their state	5 min	critical
Login gate not Running while it should be	10 min	critical
Other system servers (lobby) not Running while they should be	10 min	warning
A user server in Failed (§2)	5 min	warning
A backup, restore or reaper Job failed in the last 24h	at once, once	warning
The reaper CronJob last succeeded over 26h ago (§10)	at once	warning
Node NotReady, or kubelet reports Disk/Memory/PID pressure (§13b)	2–5 min	critical
PostgreSQL unreachable	3 min	critical
The game proxy (felis-velocity) refuses connections on the game port	3 min	critical
Newest control-plane database backup over 26h old, or none (§16)	10 min	critical
A watched filesystem below 15% free (below 5%: critical)	15 min (5 min)	warning
Host memory available below 10%	15 min	warning

How it mails:

• Recipients are the verified email addresses of enabled owner accounts. The relay is the [smtp] one sign-in codes use.
• One mail per run, holding everything that came due: new problems, a daily reminder for each problem still open, and a resolved notice once a problem has stayed gone for 10 minutes. A condition that heals before its delay is never mailed; one that turns critical is mailed again at once.
• During an install nothing is mailed. bootstrap.sh writes /run/felis/watchdog-quiet-until and removes it when it exits.
• Caching: the relay password and the recipient list are cached in /var/lib/felis/watchdog/state.json (root-only). An outage of PostgreSQL or of the API server can therefore still be mailed.
• No relay or no verified owner address: each alert is written to the journal only.

Commands:

journalctl -u felis-watchdog -n 40          # every check of the latest runs
sudo felis watchdog -dry-run                # run the checks now; mail nothing, change nothing
systemctl list-timers felis-watchdog.timer  # when it last and next runs

A healthy run logs every check passed. Otherwise it logs one line per finding, and the mail's subject once one is sent.

A -dry-run from a shell uses the command's defaults, and those do not include the game-proxy check. The unit carries -proxy-addr 127.0.0.1:<game port> and the disk list the install chose. systemctl cat felis-watchdog shows both.

Metrics

All four mandated metrics have real producers; scrape them when triaging:

• felis_servers_total — managed server count.
• felis_server_phase{server,role,phase,desired} — 1 for each server's current phase. role is login/lobby for system servers and empty for user servers. desired tells a server that is down on purpose from one that failed to come up.
• felis_build_info{component,version} — 1 on the process serving it (operator or api). Its absence is how an alert tells which process is down.
• felis_start_duration_seconds — histogram, observed once per start when readiness is first reached (ReadySignalAt − StartRequestedAt). A start that never completes (§1) contributes nothing here — absence of observations is itself the signal that starts are hanging.
• felis_image_build_failures_total — increments on build Job failure (§8d).
• felis_reaper_worlds_deleted_total — increments only after a world PVC is actually deleted post-backup (§10); a spike here means worlds crossed the 15d idle line — cross-check that join events are flowing (§10 risk vectors).

Scraping

The series come from two processes. Both Services carry the prometheus.io/scrape|port|path annotations, so a Prometheus that discovers annotated Service endpoints picks them up as is.

• felis-operator :8080/metrics (Service felis-operator-metrics) — felis_servers_total, felis_server_phase, felis_start_duration_seconds, felis_build_info{component="operator"}, and controller-runtime's controller_runtime_reconcile_* / workqueue_* series.
• felis-api internal face :8081/metrics (Service felis-api-internal) — felis_build_info{component="api"}, felis_image_build_failures_total, and the sign-in series of §17 (felis_mail_total, felis_rate_limited_total, felis_auth_otp_lockouts_total, felis_auth_failures_total, felis_sessions_revoked_total, felis_audit_write_failures_total). Unauthenticated like the probes; ClusterIP-only, and the external face never serves it.
• felis_reaper_worlds_deleted_total is produced inside the one-shot reaper CronJob, which exits long before any scrape interval — without a pushgateway it has no scrape path. Read the reaper Pod log or the world_backups table for deletions instead.

Alert rules

deploy/alerts/ ships ready-made rules for these groups:

• Control plane: felis-operator or felis-api down or unscraped (FelisOperatorDown, FelisAPIDown).

• Servers: the login gate or another system server not running (FelisLoginGateDown, FelisSystemServerDown), and a user server in Failed (FelisServerFailed).

• Operator reconcile: errors piling up (FelisReconcileErrors), and a pass stuck past its 3-minute bound (FelisReconcileStuck). The operator's liveness probe restarts a pod whose pass passes 10 minutes; its readiness waits for the informer caches to sync.

• World Jobs (kube-state-metrics): a failed backup/restore/reaper Job (FelisWorldJobFailed) and a reaper that has not succeeded in 26h (FelisReaperStale).

• Builds and starts: build failures and slow starts.

• Node: disk and memory thresholds, and the kubelet DiskPressure condition.

• Database backups: control-plane backup freshness (§16; needs node-exporter's textfile collector).

• Sign-in abuse (§17): the mail budget, relay failures, throttled floods, account code locks and the refused sign-in rate, plus lost audit rows.

• Plain Prometheus: add felis-alerts.yaml to rule_files. Check and unit-test it standalone with promtool check rules felis-alerts.yaml and promtool test rules felis-alerts_test.yml (the tests pin exactly when each alert fires).

• kube-prometheus-stack / prometheus-operator: kubectl apply -f felis-prometheusrule.yaml (adjust its release: label to your stack's ruleSelector).

---

15. Control-plane upgrades, and rolling back a bad one

There is no in-place updater: an upgrade is re-running the installer (curl -fsSL <installer URL> | sudo bash), which rebuilds/re-imports the image and re-applies the bundle. (sudo felis setup is not this path; on a completed install it only opens the config console.) The channel is not persisted across the re-run, so pass FELIS_VERSION_BOOTSTRAP=dev on a host that tracks main. Two properties of the control plane matter when you do:

• Both Deployments use strategy Recreate (single replica, no leader election: two overlapping instances would fight over the same cluster). An upgrade takes the panel/API down for the rollout window — seconds normally, longer if the new image still has to be imported.
• If the new pod cannot start (bad tag, missing image), the installer's rollout wait fails after 180s and prints kubectl describe diagnostics: you see ErrImagePull/ImagePullBackOff there instead of a silent hang.

Roll back with:

kubectl -n felis rollout undo deploy/felis-api
kubectl -n felis rollout status deploy/felis-api

(the same for felis-operator and registry). rollout undo returns to the previous ReplicaSet, whose image is normally still on the node; if the image GC collected it, the registry re-serves it automatically (§13b) for every tag the installer built — only hand-built tags need a manual re-mirror.

rollout undo reverts the image only. The upgrade's database migrations stay applied; when they are the problem, restore the pre-migrate bundle the upgrade took (§16, "Roll back an upgrade that broke the database").

15b. Game images, pinned builds, and moving a world to a newer Minecraft

The platform's game images live under mutable tags (registry.felis.svc:5000/felis/paper:demo): every installer run resolves the newest Paper/Limbo release and pushes the new build over the same tag. A server never follows that tag on its own. felis-api stores the image a server is created with pinned to the digest the tag named at that moment (…/felis/paper:demo@sha256:…), and the installer's pin_user_server_images step pins any older server still on a bare tag before it pushes the new builds. Kubernetes pulls a digest-qualified ref by the digest, so a pinned server wakes on exactly the build it was created on, however often the tag moves.

Each installer run also pushes every game build under a tag no later run rewrites, <Minecraft version>-<12 hex of the image id> (felis/paper:26.2-3f9c0a1b2c4d). Whitelist one of those to create servers on a specific Minecraft version after :demo has moved on.

Moving an existing world to a newer build is an explicit step: pick the image in the panel's Edit server dialog (re-picking the current tag moves it to that tag's newest build) and tick the backup confirmation. Over the API the same PATCH needs "confirmImageChange": true, or it is refused with 409 image_change_unconfirmed. Back the world up first: Minecraft upgrades chunks as it loads them, and the old version cannot open them again. The audit log keeps image_from/image_to for every change, so the exact previous build can be set back (it is admitted by its tag) together with a restore of the pre-upgrade backup.

Symptom	Cause	Fix
Create/edit refused with image_not_in_registry	the whitelisted tag was never pushed to the internal registry, or was deleted	push or rebuild the image, then retry
Create/edit refused with registry_unavailable	felis-api could not reach registry.felis.svc:5000	kubectl -n felis get pods -l app.kubernetes.io/component=registry; check the felis-registry-ingress NetworkPolicy still admits felis-api
Installer warns could not pin every user server	the registry was down, or a server names a tag the registry lost	fix the registry, then sudo felis pin-images before starting those servers; a server whose tag is gone keeps its bare tag until an admin picks a new image
A running server restarted during an installer re-run	it was pinned in place: the operator rolled it onto the pinned ref, the build it already ran	nothing; it happens once per server

16. Control-plane database backups and disaster recovery

The PostgreSQL database behind felis-api holds everything that is not a world: accounts, passkeys, Minecraft account links, server ownership, quotas, audit logs, and the world_backups index that maps an archive (§10) back to its owner. Losing it orphans every world archive. It lives on the host (not in k3s), so it is backed up on the host too.

What runs, and where the bundles go

• felis-db-backup.timer runs felis db backup daily at FELIS_DB_BACKUP_TIME (default *-*-* 03:30:00, plus up to 15 min random delay). Persistent=true catches up at boot after the host was off at that time. The installer takes the first backup during the install, so a broken pipeline shows up there. [CODE-ONLY; unit and timer content GO-TESTED in deploy/bootstrap_test.sh]
• Every upgrade (felis migrate up, which the installer runs) takes a pre-migrate bundle first when the database already has data and a migration is pending, and applies nothing if that backup fails (pre-migration backup failed, nothing applied). [GO-TESTED]
• Every restore takes a pre-restore bundle of the database it is about to replace (skip with -no-safety-backup). [GO-TESTED]

Bundles land in FELIS_DB_BACKUP_DIR (default /var/lib/felis/db-backups, mode 0700; outside /var/lib/rancher so a k3s reinstall cannot take them along). One bundle is felis-db-<UTC stamp>-<label>.tar:

Member	Content
MANIFEST.json	version, schema version, pg_dump --version, sha256 of every member
db.dump	pg_dump --format=custom of the felis database
state/etc/felis/...	secrets.env (DB password, session/forwarding secrets, registry tokens), felis.host.toml, felis.pod.toml, the felis.toml symlink, the panel TLS pair. bootstrap.done is left out on purpose
k8s/minecraftservers.json	every MinecraftServer, status and server-side metadata stripped, ready for kubectl apply (best effort: when the cluster did not answer, the manifest records why)

next to a .sha256 sidecar in sha256sum format. A bundle contains the secrets; treat it like /etc/felis itself. Retention per label: daily 14 (FELIS_DB_BACKUP_KEEP), pre-migrate 10, pre-restore 5, manual never pruned.

Installer knobs: FELIS_DB_BACKUP_DIR, FELIS_DB_BACKUP_KEEP, FELIS_DB_BACKUP_TIME, FELIS_DB_BACKUP_METRICS and FELIS_PRE_MIGRATE_BACKUP (below).

Is the newest backup fresh?

Three places answer, all with the same 26 h limit:

• The panel: 管理 → 维护与备份 shows the newest backup, its kind and size, and turns red with the fix commands when it is missing or overdue (read from the db_backup_last platform setting each backup writes).
• sudo felis db check exits 1 with the reason; sudo felis db list shows every bundle with its age.
• Prometheus: FelisDBBackupStale (critical) and FelisDBBackupMetricMissing (warning) in deploy/alerts/. They read felis_db_backup_last_success_timestamp_seconds, which each daily run writes to FELIS_DB_BACKUP_METRICS (default /var/lib/node_exporter/textfile_collector/felis_db_backup.prom). Point node-exporter's --collector.textfile.directory at that directory, or FelisDBBackupMetricMissing fires after 2 h.

When a backup is overdue:

sudo systemctl status felis-db-backup.timer          # enabled? next run?
sudo journalctl -u felis-db-backup -n 50 --no-pager   # why the last run failed
sudo felis db backup                                  # take one now (label manual)

Common failures: PostgreSQL down (pg_dump: ... connection refused); the backup directory's disk full (the half-written .partial is removed and the previous bundles stay intact); pg_dump: server version mismatch when an external database is newer than the host's client tools (install the matching postgresql client package).

Check a bundle

sudo felis db verify felis-db-20260924T033012Z-daily.tar   # bare names resolve in the backup dir
sha256sum -c felis-db-20260924T033012Z-daily.tar.sha256    # on a copy, without felis

verify checks the sidecar, every member against the manifest, that nothing is missing or unlisted, and that the manifest comes first. It does not touch the database.

Restore on the same host (undo a mistake)

kubectl -n felis scale deployment felis-api felis-operator --replicas=0
sudo felis db restore -yes felis-db-20260924T033012Z-daily.tar
sudo felis migrate up -config /etc/felis/felis.host.toml
kubectl -n felis scale deployment felis-api felis-operator --replicas=1

• Without -yes, restore prints what the bundle holds and exits 2.
• It refuses while other clients are connected (other clients are connected to the database (N)) and prints the scale command; -force overrides, for a client you know is idle.
• The replay is one transaction: it drops everything the felis role owns and loads the dump. Any failure rolls back and leaves the database exactly as it was (rolled back, the database is unchanged, with the psql and pg_restore errors). [GO-TESTED]
• The database before the restore is in the pre-restore bundle it names; restoring that one undoes the restore.
• migrate up brings an older bundle's schema up to the running release. Nothing migrates at startup, so skip it only when you are rolling back to the release that wrote the bundle (next section).
• Restore replaces the database only. World data (PVCs and archives, §10, §13) is not in the bundle and is not touched; a server created after the bundle keeps its PVC but loses its owner row.

Roll back an upgrade that broke the database

The installer's migrations only roll forward. The pre-migrate bundle taken by the upgrade is the way back:

kubectl -n felis scale deployment felis-api felis-operator --replicas=0
sudo felis db list | grep pre-migrate                  # newest one is the upgrade's
sudo felis db restore -yes <that bundle>
kubectl -n felis rollout undo deploy/felis-api
kubectl -n felis rollout undo deploy/felis-operator
kubectl -n felis scale deployment felis-api felis-operator --replicas=1

Do not run felis migrate up here: the host binary is already the new release and would re-apply the migrations you are rolling back. Re-run the older installer version to bring the host binary back in line.

Rebuild on a new host (the old one is gone)

This needs the off-site copy (next section) or a bundle you copied off the old host yourself, plus the off-site encryption key if the copy is in the bucket.

1. Get the newest bundle. From the bucket, with any felis binary of the same or a newer release (the felis-linux-<arch> release asset runs on its own; this works from any machine that can reach the bucket):

   export FELIS_OFFSITE_ACCESS_KEY=... FELIS_OFFSITE_SECRET_KEY=... FELIS_OFFSITE_KEY=...
   sudo -E felis offsite fetch-db -endpoint https://s3.example.com -bucket felis-backups \
        [-region ...] [-prefix ...] latest
   

   It writes the bundle into /var/lib/felis/db-backups (-dir to change), checks it (felis db verify) and names it. A wrong key fails with object does not decrypt with this key and writes nothing. For a copy you made yourself, check it with sha256sum -c felis-db-....tar.sha256.

2. Put the old host's state in place before installing, so the installer reuses the same DB password, session secret, forwarding secret and the [offsite] bucket with its credentials and key (offsite.env):

   sudo install -d -m 0700 /etc/felis
   sudo tar -xpf felis-db-....tar -C / --strip-components=1 state/etc/felis
   

3. Run the installer as for a first install. bootstrap.done is not in the bundle, so it takes the fresh-install path, creates the empty database with the restored password and migrates it. It finds [offsite] in the restored felis.host.toml and turns the hourly copy back on.

4. Restore the database and bring the servers back:

   kubectl -n felis scale deployment felis-api felis-operator --replicas=0
   sudo felis db restore -yes -no-safety-backup /var/lib/felis/db-backups/felis-db-....tar
   sudo felis migrate up -config /etc/felis/felis.host.toml
   kubectl -n felis scale deployment felis-api felis-operator --replicas=1
   tar -xOf felis-db-....tar k8s/minecraftservers.json | kubectl apply -f -
   

5. Bring the world archives back into the archive volume:

   sudo felis offsite fetch-worlds
   

   It fetches every archive the restored world_backups index lists as present and the volume lacks, provisioning the felis-backups volume first if nothing has used it yet (a short-lived felis-bind-felis-backups-* pod). It lists any it could not find in the bucket. Restore a world from its archive as usual (§10, §13). Custom images built on the old host are rebuilt from their submissions (§8), or re-pushed.

Keep a copy somewhere else

A bundle on the same disk as the database protects against mistakes and bad upgrades, and a world archive on the same disk as the worlds protects against a deleted server. Neither survives losing the disk. The installer's off-site copy sends both to an S3-compatible bucket (AWS S3, Cloudflare R2, Backblaze B2, MinIO, ...), encrypted on this host:

FELIS_OFFSITE_ENDPOINT=https://<account>.r2.cloudflarestorage.com \
FELIS_OFFSITE_BUCKET=felis-backups \
FELIS_OFFSITE_ACCESS_KEY=... FELIS_OFFSITE_SECRET_KEY=... \
  bash deploy/bootstrap.sh          # or the curl | sudo bash one-liner

Optional: FELIS_OFFSITE_REGION, FELIS_OFFSITE_PREFIX (a key prefix, so one bucket can hold several installs) and FELIS_OFFSITE_DB_KEEP (default 30). The installer writes [offsite] into felis.toml, keeps the credentials and a generated encryption key in /etc/felis/offsite.env (mode 0600), and prints the key once. Store it in a password manager: the bucket holds only sealed objects, and without the key they cannot be read. A later re-run keeps the key; it refuses a FELIS_OFFSITE_KEY that differs from the one in offsite.env, since every object already in the bucket is sealed with it. Without a bucket the installer ends with NO OFF-SITE COPY.

What runs:

• felis-offsite.timer runs felis offsite sync hourly (plus up to 10 min random delay, Persistent=true). Each run copies every world archive whose row has no offsite_at yet and records it, copies the newest db_keep database bundles the bucket lacks and prunes older ones there, and deletes a world archive from the bucket once its row has been deleted and its retention (expires_at) has passed. An object already in the bucket at the right size is recorded without being sent again, so a run cut short resumes. [GO-TESTED: internal/offsite]
• Objects are worlds/<archive>.fenc and db/<bundle>.fenc: AES-256-GCM in 64 KiB segments, so truncation, reordering and a wrong key are all refused on the way back.
• The reaper deletes an idle world only after its archive is in the bucket (§10).
• The watchdog mails the owners when no sync has completed for 12 hours (the off-site copy last completed ... ago).

Checking it:

sudo felis offsite status        # last run, errors, what the bucket holds, what waits
sudo felis offsite list          # the bundles in the bucket, newest first
sudo journalctl -u felis-offsite -n 50 --no-pager
sudo systemctl start felis-offsite.service   # run one now

status exits 1 when no sync has completed in 12 hours. missing: lines are archives the database records but the volume no longer has (an archive removed by hand); there is nothing left to copy for those.

To change the bucket, edit [offsite] in /etc/felis/felis.host.toml (and offsite.env for new credentials) and re-run the installer; to turn the copy off, delete the section and re-run. Keeping the same key across buckets keeps old copies readable.

Without a bucket, copy the backup directory off the host on a schedule of your own (rsync -a root@felis-host:/var/lib/felis/db-backups/ /backups/felis-db/, with the .sha256 sidecars; sha256sum -c on the far side proves the copy). That covers the database only; the world archives are under the felis-backups volume's directory in /var/lib/rancher/k3s/storage/.

FELIS_PRE_MIGRATE_BACKUP=0

Skips the pre-migration snapshot (migrate up -no-backup). The installer warns loudly when it is set. Use it only when the snapshot cannot work and you have another backup, e.g. an external database newer than the host's pg_dump.

17. Sign-in refused with 429, mail budget, account code locks, failed sign-ins

The public sign-in doors (/api/v1/auth/* except logout and the op-login status poll) have three limits of their own. Each answers 429 with a Retry-After header and a distinct error code.

rate_limited: one address called the doors too often

Each client address gets 20 calls at once, refilled at 20 a minute, shared across every door. A person signing in makes three or four calls, so this only bites scripts. IPv6 clients share one limit per /64. Refusals count in felis_rate_limited_total{scope="auth_door"}; FelisSignInFlood fires when more than 10 a minute are refused for 10 minutes.

The address comes from [auth] client_ip_header:

• Behind the Cloudflare tunnel it is CF-Connecting-IP. The edge setup writes it, and an install with an access_jwt_aud implies it. The header is trustworthy there because the same setup fences the panel NodePort to loopback, so every request reaching the API came through cloudflared.
• Behind your own reverse proxy it is X-Forwarded-For (the rightmost entry, the one your proxy appended). Firewall the NodePort so only the proxy reaches it, or a direct caller can write any address it likes.
• Unset, the TCP peer is used. Behind any proxy every visitor then shares the proxy's address and one limit, so everyone gets rate_limited at once. The felis api log says at start which it keys on (sign-in rate limit keys on ...). Set the header in /etc/felis/felis.toml and /etc/felis/felis.pod.toml, then felis converge.

mail_rate_limited: the install-wide mail budget is spent

Every code and notice the API mails spends one token of a single budget, [smtp] max_per_hour (default 120; a quarter of it may go at once), so a flood cannot burn the relay's quota and get the sending account suspended. While it is spent, every address gets the same 429 and nothing reaches the relay. felis_mail_total{result="throttled"} counts refusals and FelisMailBudgetExhausted fires on the first one. Look at felis_rate_limited_total first: a flood shows there. If sign-ins are real, raise max_per_hour to what your relay allows.

FelisMailDeliveryFailing is the other half: the relay itself refused mail (felis_mail_total{result="failed"}, 502 mail_undeliverable to the caller). The relay's reason is in the felis-api log.

otp_account_locked: ten wrong codes in 24 hours

Ten wrong email codes for one account within 24 hours, counted across every code it was sent, lock that account's email-code sign-in until 24 hours after the first miss. The public doors answer a locked account exactly like a wrong code, and the owner gets one mail saying so. Signed-in doors (email verification, migration step-up) answer 429 otp_account_locked. Passkey sign-in keeps working. Each lock is audited as auth.otp.locked and counted in felis_auth_otp_lockouts_total{purpose} (FelisOTPAccountLocked).

To lift a lock early once you have confirmed the owner locked themselves out:

sudo -u postgres psql felis -c \
  "DELETE FROM otp_failure_windows WHERE user_id = (SELECT id FROM users WHERE username = '<name>');"

Who tried: the audit trail

Every refused sign-in writes an auth.<door>.failed row (payload reason: bad_code, no_account, staff_account, not_staff, bad_assertion, ...) and counts in felis_auth_failures_total{door,reason}; FelisSignInFailures fires above 30 in 15 minutes. The first refusal of each throttled burst writes auth.rate_limited with the source address. Rows carry actor_user_id (the account, the column to attribute by), client_ip (the same address the limit keys on) and user_agent. actor is display text: a verified email or the username, never an address the caller set without verifying.

sudo -u postgres psql felis -c "
  SELECT created_at, action, actor, client_ip, payload->>'reason' AS reason
  FROM audit_logs
  WHERE action LIKE 'auth.%' AND created_at > now() - interval '1 hour'
  ORDER BY created_at DESC LIMIT 50;"

A failed audit write does not fail the action; it logs audit: lost ... in felis-api and counts in felis_audit_write_failures_total (FelisAuditWriteFailing). The cause is almost always PostgreSQL (§16).

Optional: a Cloudflare rate limiting rule in front

The limits above live in the API, so they hold on any edge. Behind Cloudflare you can also stop floods before they reach the tunnel: Security → WAF → Rate limiting rules, match URI Path starts with /api/v1/auth/ on the console and op.console hostnames, count by IP, 30 requests per 10 seconds, action Block for 10 seconds (the Free plan's limits).

---

Quick reference: symptom → section

Symptom	Section
Stuck Starting, never Running	§1
Starting with PodNotReady (image? PVC? boot?)	§1a
RCON secret/auth/port errors	§1b, §1c
Phase Failed	§2
Players land in lobby / wrong place	§3, §4
Wake refused / rate-limited (403/409/429/503)	§3a
maintenance_in_progress; server won't start after a restore	§3b
Routing disabled, offline-mode	§4
Panel 401/403; fails-closed; audience error	§5
Local password login rejected	§5c
Internal callers 401 (service token)	§6
Link/claim 400/409/412/403/404	§7
Build push 400 / SA denied / egress hang / Failed / executor ImagePullBackOff	§8, §8e
Registry push/pull unreachable	§9
World deleted unexpectedly / backup skipped	§10
Idle auto-stop not firing; player count 0; PlayersCounted=False	§11
A config field seems ignored	§12
PVC left behind after delete	§13
Node out of disk; pods evicted / ImagePullBackOff	§13b
Which metric to scrape	§14
An alert mail from the watchdog; nothing is mailed when something breaks	§14
FelisOperatorDown / FelisAPIDown / FelisLoginGateDown / FelisReconcileStuck	§14, §1, §2
Upgrade / roll back a bad control-plane image	§15
image_change_unconfirmed / image_not_in_registry / registry_unavailable; move a world to a newer Minecraft	§15b
Database backup overdue / FelisDBBackupStale / panel shows 从未备份	§16
pre-migration backup failed, nothing applied during an upgrade	§16
Undo a mistaken change / restore the control-plane database	§16
Host lost: rebuild from a database bundle	§16
the off-site copy last completed ... ago / NO OFF-SITE COPY / reaper awaiting_offsite stays above 0	§16, §10
Sign-in 429 rate_limited for everyone at once	§17
429 mail_rate_limited / FelisMailBudgetExhausted	§17
Right code refused; otp_account_locked / FelisOTPAccountLocked	§17
FelisSignInFailures / who is guessing, from where	§17
FelisAuditWriteFailing	§17