Unverified Commit fe310743 authored by Lemon-miaow's avatar Lemon-miaow
Browse files

fix(platform): give the control plane a PriorityClass eviction shield (#8) 

A full disk made kubelet's node-pressure eviction pick control-plane pods
alongside game pods (both priority 0), and with the images existing only
in the node's containerd (air-gapped), losing the api meant a manual
image re-import. Every control-plane pod template (api/operator/reaper/
registry) now names the bundle's cluster-scoped felis-control-plane
PriorityClass: value 1,000,000, preemptionPolicy Never — eviction order
only, never preempting a running game server. The image-GC half is not
code-fixable on an air-gapped box; troubleshooting gains 13b with the
recovery path (re-run the installer to rebuild imports, or docker save |
k3s ctr images import - for one image).
parent 2b87a5a1

AUDIT-2026-09-22.md

+2 −2
Changes for AUDIT-2026-09-22.md: 2 added lines, 2 removed lines.
Original line number Diff line number Diff line
@@ -17,14 +17,14 @@ IPv6-only 接入（`ssh -6 -i ~/.ssh/id_ed25519 root@fdb2:2c26:f4e4:0:21c:42ff:f 
| 17 | **`ListPendingOpLogins` PG 少列**：接口注释承诺「joined to its staff username」，handler 输出 `username`/`created_at`，fake 正确填充；PG SQL 未 JOIN 也未取 `created_at` → 真机 pending 列表 username 为空、created_at 为 `0001-01-01` | 真机 internal `/op-login/pending` 响应 | `pgrepo.go` SQL 改为 JOIN users + 取 created_at。提交见分支 |

| 18 | **绑定码并发兑换 500**：`RedeemPlayerBindCode` 无 `FOR UPDATE`（同文件 `VerifyLinkCode` 有），且裸 INSERT。6 路并发同码兑换 → 3×HTTP 500（`users_username_key` 唯一冲突）+ 1×400 + 2×200；跨码并发同 UUID 同样会撞 | 真机四组并发测试 + API 日志 `unmapped error ... duplicate key` | 同码：码行 `FOR UPDATE`（输家干净地 400 invalid_code）；跨码：`INSERT users ... ON CONFLICT (username) DO NOTHING`+重读、`account_links ON CONFLICT (mc_uuid) DO NOTHING`（两路汇聚同一 user）。复测：同码×6=1×200+5×400、双码×2=2×200 同 ID、DB 干净、日志零 unmapped |

| 19 | **reaper CronJob 渲染位置错误，永远无法调度**：`felis manifests` 把 CronJob 渲染到控制 ns，却引用 minecraft ns 的备份 PVC（Pod 不能跨 ns 挂 PVC：真机 `FailedScheduling: persistentvolumeclaim "felis-backups" not found`）；修正 ns 后又发现 ServerAccount 也不能跨 ns 使用（`serviceaccount "felis-reaper" not found`）。而 reaper 的 Role/RoleBinding 本就在 minecraft ns | 真机三层取证（PVC/SA/调度）| CronJob 与 SA、RoleBinding subject 全部移到 `MinecraftNamespace`（提交 `e4f2cff`+`c839454`）。**修复后完整演练通过**（见下） |

| 6 | **默认安装无备份能力 + 回收链路不可达/不可用**：(a) 没有任何环节渲染归档 PVC，`FELIS_BACKUP_PVC` 永远为空 → backup/restore 恒 503；(b) bootstrap 从不下传 reaper 三旗标 → 官方安装路径根本无法启用回收；(c) 即便启用，stock k3s 的 `<root>/<pvc>` 布局不存在，且 k3s storage root 是 `0700 root:root`、reaper pod 以 uid 1000 运行 → 真机 `lstat /worlds/…: permission denied`（fail-closed 跳过，但纯空转）；(d) README 口径（“定时备份”）不实 | 真机全链路：默认渲染 PVC+env → 建服→marker→备份 202→jobs 端点 running→succeeded→改 marker→restore→读回原值 ✅；再建 resolvecheck 世界（20d idle，marker）→ CronJob 手动 Job：`evaluated=2 reaped=1`，归档含 marker、PVC+宿主目录回收、`world_backups` 得 `inactive_15d` 行、servers 行/CR 保留 ✅ | `platform/workloads.go` 渲染归档 PVC（minecraft ns、RWO 10Gi、默认 SC），`felis manifests --backup-pvc` 默认 `felis-backups`（`=` 空为显式关闭），bootstrap 统一下传 env/旗标并写 [archive] local_path；`resolveWorldDir` 新增精确 local-path 目录解析（读 PVC `spec.volumeName`，非 glob，杜绝陈旧 PV 目录顶替）；ReaperRole 增 `pvc:get`；bootstrap 设 `FELIS_WORLDS_HOST_PATH` 时给 uid 1000 授 traverse（setfacl/o+x）；README/故障手册改写。提交 `fd33fd0`+`2b87a5a` |

| 8 | **磁盘打满灾难链**：DiskPressure → kubelet 驱逐控制面（无 PriorityClass 保护）→ 镜像被 GC（无外网、registry 空）→ 全部 ImagePullBackOff；释放后约 8 分钟才恢复调度。恢复依赖人工 `docker save felis:* | k3s ctr images import -`（docker 存储是唯一副本） | 早前真机 drill；本次复核 k3s 默认驱逐顺序 | 控制面（api/operator/reaper/registry）全部挂 `felis-control-plane` PriorityClass（value 1,000,000，`preemptionPolicy: Never`）——节点压力按优先级升序驱逐，游戏 pod（0）先走，控制面留下；镜像 GC 无法用代码根治（air-gap 无回源），新增 troubleshooting §13b 固化恢复路径（重跑安装器重建导入；单镜像可 `docker save | k3s ctr images import -`）。提交见下 |



## 待决策台账（未修）



| # | 主题 | 说明 |

|---|------|------|

| 6 | 默认安装无备份能力 | backup/restore 端点默认 503（需 `FELIS_BACKUP_PVC`+PVC），reaper CronJob 需 `--backup-pvc/--archive-local-path/--worlds-host-path` 三旗标渲染，bootstrap 一个都不传；文档无说明；README 与"自动备份"口径不符。另：归档 3 个月过期依赖 reaper 清理，未启用则磁盘只增不减 |

| 7 | 异步失败不可感知 | backup/restore 失败后无状态出口：restore 行不变、backup 无行；只有集群侧 Job/日志可查。建议状态字段或 `?failed` 查询 |

| 8 | 磁盘打满灾难链 | DiskPressure → kubelet 驱逐控制面（无 PriorityClass 保护）→ 镜像被 GC（无外网、registry 空）→ 全部 ImagePullBackOff；释放后约 8 分钟才恢复调度。恢复靠 `docker save felis:* | k3s ctr images import -`（docker 守护进程存储是唯一副本，需固化回源路径）。建议：PriorityClass、镜像入内置 registry、磁盘告警 |

| 9 | 升级策略 Recreate | 单副本 + Recreate：任何控制面升级=停机；坏升级（实测错 tag）服务中断约 95s 且需人工 `rollout undo`（无自动回滚）。建议 runbook/文档化 |

| 10 | 备份语义 | 归档包含整个 /data（jar、libraries、cache），167MB；是否符合"world backup"定位待评估 |

| 11 | PG 断连表现 | 会话查询失败报 401 而非 503（fail-closed 但误导；用户以为没登录） |

docs/troubleshooting.md

+37 −0
Changes for docs/troubleshooting.md: 37 added lines, 0 removed lines.
Original line number Diff line number Diff line
@@ -577,6 +577,43 @@ changes, because retention was never conditional in the first place. 


---



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



A full disk is the one failure this platform cannot ride out by itself, because

the images exist only in the node's containerd (air-gapped by design), so a

GC'd image has no pull source.



Eviction ordering. Kubelet's node-pressure eviction removes pods in ascending

priority. Every control-plane pod (api, operator, reaper, registry) carries the

bundle's `felis-control-plane` PriorityClass (value 1,000,000,

`preemptionPolicy: Never`), while game-server pods run at the default 0 — so a

burst of running servers is evicted first and the control plane keeps serving

status/console until pressure is genuinely extreme. The class never *preempts*:

a scheduling decision will not kill a running game server to restart the api.



Symptoms of the image-GC stage: pods stuck `ImagePullBackOff`/`ErrImagePull`

with `kubectl describe pod` showing a pull attempt for a tag that plainly

exists (`k3s ctr images ls` will show it missing — the kubelet GC removed it

under imagefs pressure).



Recovery:



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. Re-import the images by re-running the installer (it rebuilds imports from

   the local Docker store, which the kubelet GC does not touch):

   `curl -fsSL <installer URL> | sudo bash` (or `sudo felis setup`), then

   `kubectl -n felis rollout status deploy/felis-api`.

3. Delete now-unschedulable stuck pods so they retry with the re-imported image.



If the API itself is down and you only need the images back without a full

installer run: `docker save felis:<tag> | k3s ctr images import -` restores one

image from the Docker store (that store is deliberately a second copy; treat it

as the recovery path, not as free space).



---



## 14. Metrics for diagnosis (spec §23)



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

internal/platform/bundle.go

+3 −1
Changes for internal/platform/bundle.go: 3 added lines, 1 removed line.
Original line number Diff line number Diff line
@@ -34,7 +34,9 @@ type Object interface { 
// Deployments and the in-cluster registry (Deployment + Service + PVC), which

// make the SAs and NetworkPolicy peers refer to something real, plus the

// world-archive PVC that backs backup/restore when a backup PVC is named (see

// workloads.go).

// workloads.go). Workloads also carries the one cluster-scoped object, the

// felis-control-plane PriorityClass (node-pressure eviction shield — a

// PriorityClass is not namespaced by design); everything else is namespaced.

// The reaper CronJob is also part of Workloads, rendered only when the retention

// storage topology is supplied (WorldsHostPath + BackupPVC + ArchiveLocalPath —

// workloads.go documents the gate and the shape-asserted hostPath caveat). The

internal/platform/workloads.go

+40 −2
Changes for internal/platform/workloads.go: 40 added lines, 2 removed lines.
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ import ( 
	appsv1 "k8s.io/api/apps/v1"

	batchv1 "k8s.io/api/batch/v1"

	corev1 "k8s.io/api/core/v1"

	schedulingv1 "k8s.io/api/scheduling/v1"

	"k8s.io/apimachinery/pkg/api/resource"

	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"

	"k8s.io/apimachinery/pkg/util/intstr"
@@ -176,11 +177,14 @@ func InternalAPIBaseURL(controlNamespace string) string { 
// felis-operator Deployment, and the in-cluster registry (Deployment + Service +

// PVC), the world-archive PVC when p.BackupPVC names it (it backs the

// backup/restore Jobs and the reaper), plus the reaper CronJob when

// reaperEnabled(p). FelisImage is required — `felis manifests` enforces it

// (fail-loud), so a rendered bundle always names a concrete image.

// reaperEnabled(p). Every pod template carries the felis-control-plane

// PriorityClass (controlPlanePriorityClass below), the node-pressure eviction

// shield. FelisImage is required — `felis manifests` enforces it (fail-loud), so

// a rendered bundle always names a concrete image.

func Workloads(p Params) []Object {

	p = p.withDefaults()

	objs := []Object{

		controlPlanePriorityClass(),

		APIDeployment(p),

		apiService(p),

		apiInternalService(p),
@@ -199,6 +203,37 @@ func Workloads(p Params) []Object { 
	return objs

}



// controlPlanePriorityName is the PriorityClass every control-plane workload runs

// under (api, operator, reaper, registry). Node-pressure eviction (a full disk

// being the realistic case on a game box) removes pods in ASCENDING priority, and

// a classless pod is priority 0 — the same as the game servers, which are exactly

// the pods a burst of joins has just filled the node with. A full disk then takes

// the api/operator down too, and recovery needs a human: with no reachable

// registry on an air-gapped box the images are gone, so the fix is a re-run of the

// installer to re-import them. The class is an eviction shield, not a preemption

// lever: PreemptionPolicy=Never, so a busy node never loses a running game server

// merely to schedule the api. Value 1,000,000 sits above every game pod (0) and

// far below the kubelet's system-reserved classes (2,000,000,000).

const (

	controlPlanePriorityName         = "felis-control-plane"

	controlPlanePriorityValue  int32 = 1_000_000

	controlPlanePriorityReason       = "Felis control plane (api/operator/reaper/registry) survives node-pressure eviction before game servers"

)



// controlPlanePriorityClass renders the cluster-scoped PriorityClass the

// control-plane pod templates reference (the ONE cluster-scoped object in the

// bundle; a PriorityClass is not namespaced by design).

func controlPlanePriorityClass() *schedulingv1.PriorityClass {

	never := corev1.PreemptNever

	return &schedulingv1.PriorityClass{

		TypeMeta:         metav1.TypeMeta{APIVersion: "scheduling.k8s.io/v1", Kind: "PriorityClass"},

		ObjectMeta:       metav1.ObjectMeta{Name: controlPlanePriorityName},

		Value:            controlPlanePriorityValue,

		PreemptionPolicy: &never,

		Description:      controlPlanePriorityReason,

	}

}



// reaperEnabled reports whether the retention CronJob should render. It needs all

// three storage coordinates: WorldsHostPath (where worlds live, mounted to read

// them), BackupPVC (where archives are written) and ArchiveLocalPath (the mount
@@ -509,6 +544,7 @@ func reaperCronJob(p Params) *batchv1.CronJob { 
						ObjectMeta: metav1.ObjectMeta{Labels: labels},

						Spec: corev1.PodSpec{

							ServiceAccountName: SAReaper,

							PriorityClassName:  controlPlanePriorityName,

							RestartPolicy:      corev1.RestartPolicyNever,

							SecurityContext:    hardenedPodSecurityContext(),

							Containers:         []corev1.Container{container},
@@ -544,6 +580,7 @@ func controlPlaneDeployment(p Params, sa string, container corev1.Container, vol 
				ObjectMeta: metav1.ObjectMeta{Labels: labels},

				Spec: corev1.PodSpec{

					ServiceAccountName: sa,

					PriorityClassName:  controlPlanePriorityName,

					SecurityContext:    hardenedPodSecurityContext(),

					Containers:         []corev1.Container{container},

					Volumes:            volumes,
@@ -591,6 +628,7 @@ func registryDeployment(p Params) *appsv1.Deployment { 
				ObjectMeta: metav1.ObjectMeta{Labels: labels},

				Spec: corev1.PodSpec{

					AutomountServiceAccountToken: boolPtr(false),

					PriorityClassName:            controlPlanePriorityName,

					SecurityContext:              hardenedPodSecurityContext(),

					Containers:                   []corev1.Container{container},

					Volumes: []corev1.Volume{

internal/platform/workloads_test.go

+56 −2
Changes for internal/platform/workloads_test.go: 56 added lines, 2 removed lines.
Original line number Diff line number Diff line
@@ -6,6 +6,7 @@ import ( 
	appsv1 "k8s.io/api/apps/v1"

	batchv1 "k8s.io/api/batch/v1"

	corev1 "k8s.io/api/core/v1"

	schedulingv1 "k8s.io/api/scheduling/v1"

	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"

	"k8s.io/apimachinery/pkg/labels"

)
@@ -459,8 +460,8 @@ func TestRegistry_DeploymentServicePVC(t *testing.T) { 
// internal Service must be present or the login pod's felis-api:8081 path is dead.

func TestWorkloads_BundleContents(t *testing.T) {

	objs := Workloads(testParams())

	if len(objs) != 8 {

		t.Fatalf("Workloads returned %d objects, want 8", len(objs))

	if len(objs) != 9 {

		t.Fatalf("Workloads returned %d objects, want 9", len(objs))

	}

	var haveInternalSvc bool

	for _, o := range objs {
@@ -477,6 +478,59 @@ func TestWorkloads_BundleContents(t *testing.T) { 
	}

}



// TestControlPlanePriorityClass pins the node-pressure eviction shield: every

// control-plane pod template (api/operator/reaper/registry) references the one

// PriorityClass, which outranks the default-0 game pods by eviction order while

// never preempting them, and is the bundle's only cluster-scoped object. Without

// this, a full disk evicts the api alongside the game pods and (no reachable

// registry on an air-gapped box) recovery needs a human re-importing images.

func TestControlPlanePriorityClass(t *testing.T) {

	objs := Workloads(reaperParams()) // include the reaper CronJob's pod template



	var class *schedulingv1.PriorityClass

	clusterScoped := 0

	deployments, cronJobs := 0, 0

	for _, o := range objs {

		if o.GetNamespace() == "" {

			clusterScoped++

		}

		switch v := o.(type) {

		case *schedulingv1.PriorityClass:

			class = v

		case *appsv1.Deployment:

			deployments++

			if v.Spec.Template.Spec.PriorityClassName != controlPlanePriorityName {

				t.Errorf("deployment %s pod priority = %q, want %q", v.Name, v.Spec.Template.Spec.PriorityClassName, controlPlanePriorityName)

			}

		case *batchv1.CronJob:

			cronJobs++

			if v.Spec.JobTemplate.Spec.Template.Spec.PriorityClassName != controlPlanePriorityName {

				t.Errorf("CronJob %s pod priority = %q, want %q", v.Name, v.Spec.JobTemplate.Spec.Template.Spec.PriorityClassName, controlPlanePriorityName)

			}

		}

	}

	if class == nil {

		t.Fatal("Workloads must render the control-plane PriorityClass")

	}

	if class.Name != controlPlanePriorityName || class.Value != controlPlanePriorityValue {

		t.Errorf("class = %s/%d, want %s/%d", class.Name, class.Value, controlPlanePriorityName, controlPlanePriorityValue)

	}

	if class.PreemptionPolicy == nil || *class.PreemptionPolicy != corev1.PreemptNever {

		t.Errorf("class preemptionPolicy = %v, want Never (an eviction shield, never a lever against running game servers)", class.PreemptionPolicy)

	}

	if clusterScoped != 1 {

		t.Errorf("bundle has %d cluster-scoped objects, want exactly the PriorityClass", clusterScoped)

	}

	if deployments != 3 || cronJobs != 1 {

		t.Errorf("scanned %d deployments / %d cronjobs, want 3 / 1 — a pod template escaped the class check", deployments, cronJobs)

	}

	// The class must outrank the default game-pod priority (0); equality would make

	// the eviction order nondeterministic between the api and a full game server.

	if controlPlanePriorityValue <= 0 {

		t.Errorf("control-plane priority %d must exceed the default 0 game-pod priority", controlPlanePriorityValue)

	}

}



// cronPodSpec returns the single container and pod template of a CronJob's Job

// template, failing if the shape is not a single-container pod (the reaper's shape).

func cronPodSpec(t *testing.T, cj *batchv1.CronJob) (corev1.PodSpec, corev1.Container) {