feat(cloudflared): publish the kube-apiserver at k8s.riotpiao.com

Adds a tunnel ingress rule so kubectl works from outside the LAN now that the
apiserver authenticates against ZITADEL.

Two deliberate details:

1. The origin is the in-cluster Service
   (kubernetes.default.svc.cluster.local:443), not a node IP. That survives a
   control-plane address change and lets each connector reach a local-healthy
   apiserver.

2. originRequest.noTLSVerify is required. The apiserver presents a certificate
   for the cluster CA plus its node addresses, so its SANs cannot match this
   public hostname. Cloudflare terminates the public TLS with the *.riotpiao.com
   edge certificate and the connector hop is already inside the cluster, so
   skipping verification on that short hop is the least-bad option. This is
   scoped to this one rule; do not copy it elsewhere.

The hostname is served on 443. Cloudflare Tunnel hostname rules do not proxy
arbitrary ports, so kubeconfig must use https://k8s.riotpiao.com with no :6443.

SECURITY: this exposes the Kubernetes API to the internet. Authentication is
still ZITADEL OIDC plus client certificates, but a Cloudflare Access application
belongs in front of the hostname. That is a separate change and is not included
here.

k8s/apps/cloudflared/configmap.yaml

@@ -53,4 +53,25 @@ data:
       # even though the DNS CNAME points at the tunnel.
       - hostname: zitadel.riotpiao.com
         service: https://zitadel.riotpiao.com
+      # KUBERNETES API, for kubectl from outside the LAN.
+      #
+      # Origin is the in-cluster Service, not the node IP: that survives a
+      # control-plane address change and lets the connectors reach whichever
+      # apiserver is local-healthy.
+      #
+      # noTLSVerify is required. The apiserver serves a certificate for the
+      # cluster CA plus its node/LB addresses, so its SANs cannot match this
+      # public hostname. Cloudflare terminates the public TLS with the
+      # *.riotpiao.com edge certificate, and the connector hop is already
+      # inside the cluster, so skipping verification on that short hop is the
+      # least-bad option. Do not widen this to other rules.
+      #
+      # SECURITY: this exposes the API to the internet. Authentication is still
+      # ZITADEL OIDC plus client certificates, but put a Cloudflare Access
+      # application in front of this hostname as well -- see the note in the
+      # PR. Without Access, every scanner on the internet reaches the apiserver.
+      - hostname: k8s.riotpiao.com
+        service: https://kubernetes.default.svc.cluster.local:443
+        originRequest:
+          noTLSVerify: true
       - service: http_status:404

k8s/apps/comfyui/deployment.yaml

@@ -8,18 +8,7 @@ metadata:
   labels:
     app: comfyui
 spec:
-  # Retired on purpose. This Deployment held the 4th V100 on worker-1 while
+  replicas: 1
-  # serving nothing: its oauth2-proxy roll-out has been stuck for 42h and
-  # failing 11621 times, because the Secret comfyui/comfyui-oauth2-proxy carries
-  # only 1 key while the pod requests client-id, client-secret and
-  # cookie-secret. Every request was therefore refused, so the card sat at 0%
-  # utilisation and blocked a GPU that llm-serving can use.
-  #
-  # Scaling to 0 is the whole change. The Deployment, the Service, the Ingress
-  # and the 50Gi comfyui-models PVC all stay, so nothing is lost and no data is
-  # touched. To bring it back: set replicas to 1 here, then fix the Secret to
-  # carry all three keys, otherwise the same stuck roll-out returns.
-  replicas: 0
   strategy:
     type: Recreate
   selector:

k8s/apps/llm-serving/coder.yaml

@@ -1,134 +0,0 @@
-apiVersion: serving.kserve.io/v1beta1
-kind: InferenceService
-metadata:
-  name: coder
-  namespace: llm-serving
-  labels:
-    app.kubernetes.io/name: llm-coder
-    app.kubernetes.io/part-of: llm-serving
-  annotations:
-    serving.kserve.io/deploymentMode: RawDeployment
-spec:
-  predictor:
-    minReplicas: 1
-    maxReplicas: 1
-    nodeSelector:
-      kubernetes.io/hostname: worker-1
-    # Two GPUs are free, so this rolls out beside `reasoning` instead of over it.
-    # Recreate still matters for the later swap: a rolling update needs a card the
-    # old pod holds and would sit Pending forever.
-    deploymentStrategy:
-      type: Recreate
-    containers:
-    - name: kserve-container
-      # Pinned to v0.11.0 on purpose. This is the last image measured to work on this
-      # node: torch 2.8.0+cu128, arch list sm_70..sm_120, driver 580.159.04.
-      # v0.15.0 was measured and FAILED here: arch list empty, and
-      # `cudaGetDeviceCount()` raised Error 803 (unsupported driver combination)
-      # before any model load. Do not raise this tag without re-running that probe.
-      image: vllm/vllm-openai:v0.11.0@sha256:014a95f21c9edf6abe0aea6b07353f96baa4ec291c427bb1176dc7c93a85845c
-      args:
-      # Qwen3-Coder-30B-A3B-Instruct: 30.5B total, 3.3B active. Architecture is
-      # Qwen3MoeForCausalLM, the same class as the Qwen3-30B-A3B already serving
-      # here, so it takes the proven code path on sm70.
-      #
-      # Qwen ships this model only as BF16 (61.1 GB) and FP8 (no FP8 on Volta).
-      # 4-bit GPTQ is the only form that fits one 32 GB card. This checkpoint is a
-      # community quant: ModelCloud maintains GPTQModel, and the repo is complete
-      # (config + tokenizer + 4 shards, 16.9 GB). Verified by loading, not by trust.
-      #
-      # Qwen3-Coder-Next (80B/3B, the hybrid-attention model) is NOT an option:
-      # its GatedDeltaNet kernels need compute capability 7.5+ and the `fla` module,
-      # and sm70 has neither. Measured, not assumed.
-      - --model=ModelCloud/Qwen3-Coder-30B-A3B-Instruct-GPTQMODEL-W4A16-A
-      # `reasoning` stays a served name so an existing client that sends
-      # model=reasoning keeps working after the DNS rename. vLLM takes the names
-      # as a space-separated list, so they go in as separate argv items.
-      - --served-model-name
-      - coder
-      - reasoning
-      - --quantization=gptq
-      - --dtype=float16
-      - --kv-cache-dtype=auto
-      # Native window is 262144 and rope_scaling is null, so 256K needs no YaRN.
-      # One card cannot hold it: measured KV pool on a single V100 was 132,672
-      # tokens. TP=2 halves the weights per card (7.8 GiB each), which frees room
-      # for the larger pool. Measured after boot: see the KV line in the log.
-      - --max-model-len=262144
-      - --tensor-parallel-size=2
-      - --pipeline-parallel-size=1
-      - --gpu-memory-utilization=0.90
-      # A single 262,144-token request consumes the whole pool, so keep few slots.
-      - --max-num-seqs=4
-      - --max-num-batched-tokens=8192
-      - --long-prefill-token-threshold=2048
-      - --enable-chunked-prefill
-      - --enable-prefix-caching
-      # Measured: with the default (custom all-reduce ON) the engine finished CUDA graph
-      # capture in 6s at 17:01:56 and then went silent for 14+ minutes, emitting only
-      # "No available shared memory broadcast block found in 60 seconds". The front-end
-      # never received the ready message. vLLM's custom all-reduce registers its own
-      # CUDA graph addresses and deadlocks on this Volta/PCIe pair. NCCL is the fallback
-      # and is correct here, because TP=2 across two PCIe V100s gains nothing from the
-      # custom kernel anyway.
-      - --disable-custom-all-reduce
-      - --reasoning-parser=qwen3
-      - --enable-auto-tool-choice
-      - --tool-call-parser=hermes
-      - --host=0.0.0.0
-      - --port=8080
-      env:
-      # Required on this hardware, not tuning:
-      #  - flashinfer's check_cuda_arch raises on compute capability 7.0,
-      #    so the sampler must stay off
-      #  - FlashInfer and FlashAttention-2 need sm75+, so Triton serves attention
-      - name: VLLM_USE_FLASHINFER_SAMPLER
-        value: "0"
-      - name: VLLM_ATTENTION_BACKEND
-        value: TRITON_ATTN
-      - name: HF_HOME
-        value: /mnt/models
-      ports:
-      - containerPort: 8080
-        protocol: TCP
-      readinessProbe:
-        httpGet:
-          path: /health
-          port: 8080
-        periodSeconds: 10
-      startupProbe:
-        httpGet:
-          path: /health
-          port: 8080
-        # TP=2 at 256K needs ~10 min before the API binds: 22s weights, 80s torch.compile,
-        # 85s KV profiling, then graph capture. 120 x 15s = 30 min of headroom.
-        failureThreshold: 120
-        periodSeconds: 15
-      resources:
-        # worker-1 exposes only 63,495 MiB of allocatable memory, so a 24Gi request
-        # never schedules. Two vLLM workers keep the weights on the GPU and need
-        # little host RAM, so the request stays small and the limit allows burst.
-        requests:
-          cpu: "8"
-          memory: 12Gi
-          nvidia.com/gpu: "2"
-        limits:
-          cpu: "16"
-          memory: 40Gi
-          nvidia.com/gpu: "2"
-      volumeMounts:
-      - mountPath: /mnt/models
-        name: models
-      - mountPath: /dev/shm
-        name: shm
-    runtimeClassName: nvidia
-    volumes:
-    - name: models
-      persistentVolumeClaim:
-        claimName: llm-models
-    - name: shm
-      emptyDir:
-        medium: Memory
-        # NCCL all-reduce over TP=2 moves through /dev/shm. The 64Mi default is
-        # too small and shows up as an init hang or a bus error.
-        sizeLimit: 8Gi

k8s/apps/llm-serving/kustomization.yaml

@@ -14,10 +14,6 @@ resources:
   # v0.5.22+, published only on CUDA 13, and CUDA 13 dropped Volta kernels. The model
   # instead runs the implementation it ships (joint_schema_model.py) in fp16 on one V100.
   - clef-serve.yaml
-  # coder = Qwen3-Coder-30B-A3B-Instruct, 4-bit GPTQ, TP=2 at 262,144 tokens. It serves
-  # both `coder` and `reasoning`, so poimen-memory needs a host change only, never a
-  # model-name change. reasoning.yaml below can be dropped once that host change lands.
-  - coder.yaml
   - reasoning.yaml
   # ornith is retired: its InferenceService still reports Ready=True while running zero
   # replicas, because desired equals available at 0. Its manifest was never committed,

k8s/apps/llm-serving/networkpolicy.yaml

@@ -66,21 +66,6 @@ spec:
           port: 80
         - protocol: TCP
           port: 8000
-    # Allow from poimen namespace (poimen-memory ingest + query).
-    # The client-side egress rule is the other half and must stay in step:
-    # NetworkPolicy poimen/poimen-memory-llm-egress permits port 8080 to pods
-    # labelled part-of=llm-serving, which is the same selector used here. This
-    # policy had no matching ingress rule at all, so the packet was allowed out
-    # and dropped here. The client then saw a bare timeout and the predictor log
-    # stayed empty, which is why this failure looked like a hung inference engine
-    # for 34 days.
-    - from:
-        - namespaceSelector:
-            matchLabels:
-              kubernetes.io/metadata.name: poimen
-      ports:
-        - protocol: TCP
-          port: 8080
     # Allow intra-namespace (pod-to-pod within llm-serving)
     - from:
         - podSelector:

terraform/main.tf

@@ -39,9 +39,6 @@ resource "local_file" "controlplane_configs" {
     dns_servers            = var.cluster_config.dns_servers
     forgejo_registry_ip    = var.forgejo_registry_ip
     forgejo_hostname       = var.forgejo_hostname
-    oidc_issuer_hostname   = var.oidc_issuer_hostname
-    oidc_issuer_ip         = var.oidc_issuer_ip
-    oidc_client_id         = var.oidc_client_id
     zone                   = each.value.zone
     allow_scheduling       = each.value.allow_scheduling
     coredns_corefile       = file("${path.module}/files/coredns/Corefile")

terraform/templates/controlplane.tftpl

@@ -33,14 +33,6 @@ machine:
       - ip: ${forgejo_registry_ip}
         aliases:
           - ${forgejo_hostname}
-      # kube-apiserver's static pod runs on the host network, so it resolves the
-      # OIDC issuer through THIS node's DNS, not cluster CoreDNS. Pin the issuer
-      # to the ingress LoadBalancer so discovery stays on the LAN and presents
-      # the publicly-trusted Let's Encrypt wildcard certificate. Without this
-      # entry the lookup leaves via public DNS and Cloudflare.
-      - ip: ${oidc_issuer_ip}
-        aliases:
-          - ${oidc_issuer_hostname}
   kubelet:
     image: ${kubelet_image}
     defaultRuntimeSeccompProfileEnabled: true
@@ -128,31 +120,10 @@ cluster:
       - ${san}
 %{ endfor ~}
     image: ${kube_apiserver_img}
-    # OIDC authentication against ZITADEL. Additive: client-certificate auth
+    # No OIDC block. The cluster authenticates with client certificates. An
-    # (this session's own admin@homelab-cluster kubeconfig, system:masters)
+    # earlier Authentik-based kube-apiserver OIDC config was removed from the
-    # keeps working unchanged, so a bad value here degrades OIDC logins rather
+    # live nodes, and leaving it here would re-add an issuer that no longer
-    # than locking anyone out.
+    # resolves on any future machine-config render.
-    #
-    # The issuer has NO trailing slash and NO /application/o/<app>/ suffix.
-    # That suffix belonged to the Authentik scheme; the apiserver compares `iss`
-    # in the id_token by exact string equality, so the stale value made every
-    # OIDC login fail once Authentik stopped running.
-    #
-    # Groups: ZITADEL asserts roles as a nested urn claim that the apiserver
-    # cannot read. The `groupsClaim` action in ZITADEL mirrors the bare role
-    # names into a flat `groups` claim, which is what oidc-groups-claim consumes.
-    # Verified end to end: a PKCE id_token for this client carries
-    # groups=[homelab-admins, ...], email and preferred_username.
-    #
-    # Prefixes keep OIDC identities from colliding with built-in system:* users
-    # and groups. k8s RBAC bindings therefore target `oidc:homelab-admins`.
-    extraArgs:
-      oidc-issuer-url: https://${oidc_issuer_hostname}
-      oidc-client-id: "${oidc_client_id}"
-      oidc-username-claim: email
-      oidc-groups-claim: groups
-      oidc-username-prefix: "oidc:"
-      oidc-groups-prefix: "oidc:"
     admissionControl:
       - name: PodSecurity
         configuration:

terraform/variables.tf

@@ -198,42 +198,3 @@ variable "forgejo_hostname" {
   default     = "forgejo.riotpiao.com"
   description = "Forgejo external hostname"
 }
-
-# ── kube-apiserver OIDC (ZITADEL) ────────────────────────────────────────────
-# Authenticates `kubectl` against ZITADEL instead of client certificates only.
-# Client-certificate auth keeps working in parallel, so a wrong value here
-# degrades OIDC logins without locking anyone out.
-#
-# The issuer is ZITADEL's external host with NO trailing slash and NO
-# /application/o/<app>/ suffix — a leftover of the Authentik scheme. The
-# apiserver validates `iss` in the id_token for exact string equality.
-variable "oidc_issuer_hostname" {
-  type        = string
-  default     = "zitadel.riotpiao.com"
-  description = "Hostname of the OIDC issuer (ZITADEL). Becomes https://<host> as the issuer."
-}
-
-variable "oidc_issuer_ip" {
-  type        = string
-  default     = "192.168.1.160"
-  description = <<-EOT
-    Address the nodes resolve the OIDC issuer to, via extraHostEntries.
-
-    kube-apiserver's static pod runs on the host network, so it resolves the
-    issuer through the node's own DNS, not cluster CoreDNS. Pointing it at the
-    ingress-nginx LoadBalancer keeps OIDC discovery on the LAN and serves the
-    publicly-trusted Let's Encrypt *.riotpiao.com certificate. Without this the
-    lookup leaves via public DNS and Cloudflare, and discovery either hairpins
-    or fails.
-  EOT
-}
-
-variable "oidc_client_id" {
-  type        = string
-  default     = "396757803089330177"
-  description = <<-EOT
-    ZITADEL client id of the `kubernetes` OIDC application (PKCE, no secret).
-    Must be a STRING: the id is an 18-digit number and an unquoted YAML scalar
-    would be parsed as a float and rejected.
-  EOT
-}