add pvc-autoresizer for automatic PVC expansion before volumes fill up [ci skip]

Deploy topolvm/pvc-autoresizer controller that monitors kubelet_volume_stats
via Prometheus and auto-expands annotated PVCs. Annotated all 9 block-storage
PVCs (proxmox-lvm) with per-PVC thresholds and max limits. Updated PVFillingUp
alert to critical/10m (means auto-expansion failed) and added PVAutoExpanding
info alert at 80%.

stacks/dbaas/modules/dbaas/main.tf

@@ -157,6 +157,13 @@ resource "helm_release" "mysql_cluster" {
 
     datadirVolumeClaimTemplate = {
       storageClassName = "proxmox-lvm"
+      metadata = {
+        annotations = {
+          "resize.topolvm.io/threshold"     = "80%"
+          "resize.topolvm.io/increase"      = "20%"
+          "resize.topolvm.io/storage_limit" = "100Gi"
+        }
+      }
       resources = {
         requests = {
           storage = "30Gi"
@@ -897,6 +904,11 @@ resource "null_resource" "pg_cluster" {
             search_path: '"$user", public'
           enableAlterSystem: true
         enableSuperuserAccess: true
+        inheritedMetadata:
+          annotations:
+            resize.topolvm.io/threshold: "80%"
+            resize.topolvm.io/increase: "20%"
+            resize.topolvm.io/storage_limit: "100Gi"
         storage:
           size: 20Gi
           storageClass: proxmox-lvm

stacks/ebooks/main.tf

@@ -145,6 +145,11 @@ resource "kubernetes_persistent_volume_claim" "calibre_config_iscsi" {
   metadata {
     name      = "ebooks-calibre-config-proxmox"
     namespace = kubernetes_namespace.ebooks.metadata[0].name
+    annotations = {
+      "resize.topolvm.io/threshold"     = "80%"
+      "resize.topolvm.io/increase"      = "50%"
+      "resize.topolvm.io/storage_limit" = "10Gi"
+    }
   }
   spec {
     access_modes       = ["ReadWriteOnce"]

stacks/monitoring/modules/monitoring/prometheus.tf

@@ -4,6 +4,11 @@ resource "kubernetes_persistent_volume_claim" "prometheus_server_pvc" {
   metadata {
     name      = "prometheus-data-proxmox"
     namespace = kubernetes_namespace.monitoring.metadata[0].name
+    annotations = {
+      "resize.topolvm.io/threshold"     = "90%"
+      "resize.topolvm.io/increase"      = "10%"
+      "resize.topolvm.io/storage_limit" = "500Gi"
+    }
   }
 
   spec {

stacks/monitoring/modules/monitoring/prometheus_chart_values.tpl

@@ -801,13 +801,20 @@ serverFiles:
               severity: warning
             annotations:
               summary: "Disk {{ $labels.mountpoint }} on {{ $labels.instance }}: {{ $value | printf \"%.1f\" }}% free (threshold: 10%)"
+          - alert: PVAutoExpanding
+            expr: (kubelet_volume_stats_used_bytes / kubelet_volume_stats_capacity_bytes) * 100 > 80 and kubelet_volume_stats_capacity_bytes < 1099511627776
+            for: 5m
+            labels:
+              severity: info
+            annotations:
+              summary: "PV {{ $labels.persistentvolumeclaim }} in {{ $labels.namespace }}: {{ $value | printf \"%.0f\" }}% used — auto-expansion should trigger"
           - alert: PVFillingUp
             expr: (kubelet_volume_stats_used_bytes / kubelet_volume_stats_capacity_bytes) * 100 > 95 and kubelet_volume_stats_capacity_bytes < 1099511627776
-            for: 30m
+            for: 10m
             labels:
-              severity: warning
+              severity: critical
             annotations:
-              summary: "PV {{ $labels.persistentvolumeclaim }} in {{ $labels.namespace }}: {{ $value | printf \"%.0f\" }}% used (threshold: 95%)"
+              summary: "PV {{ $labels.persistentvolumeclaim }} in {{ $labels.namespace }}: {{ $value | printf \"%.0f\" }}% used — auto-expansion may have failed"
           - alert: PVPredictedFull
             expr: predict_linear(kubelet_volume_stats_used_bytes[6h], 3600*24) > kubelet_volume_stats_capacity_bytes
             for: 1h

stacks/nextcloud/main.tf

@@ -188,6 +188,11 @@ resource "kubernetes_persistent_volume_claim" "nextcloud_data_iscsi" {
   metadata {
     name      = "nextcloud-data-proxmox"
     namespace = kubernetes_namespace.nextcloud.metadata[0].name
+    annotations = {
+      "resize.topolvm.io/threshold"     = "80%"
+      "resize.topolvm.io/increase"      = "20%"
+      "resize.topolvm.io/storage_limit" = "100Gi"
+    }
   }
   spec {
     access_modes       = ["ReadWriteOnce"]

stacks/novelapp/main.tf

@@ -50,6 +50,11 @@ resource "kubernetes_persistent_volume_claim" "novelapp-data" {
   metadata {
     name      = "novelapp-data-proxmox"
     namespace = kubernetes_namespace.novelapp.metadata[0].name
+    annotations = {
+      "resize.topolvm.io/threshold"     = "80%"
+      "resize.topolvm.io/increase"      = "100%"
+      "resize.topolvm.io/storage_limit" = "5Gi"
+    }
   }
   spec {
     access_modes       = ["ReadWriteOnce"]

stacks/plotting-book/main.tf

@@ -50,6 +50,11 @@ resource "kubernetes_persistent_volume_claim" "plotting-book-data" {
   metadata {
     name      = "plotting-book-data-proxmox"
     namespace = kubernetes_namespace.plotting-book.metadata[0].name
+    annotations = {
+      "resize.topolvm.io/threshold"     = "80%"
+      "resize.topolvm.io/increase"      = "100%"
+      "resize.topolvm.io/storage_limit" = "5Gi"
+    }
   }
   spec {
     access_modes       = ["ReadWriteOnce"]

stacks/pvc-autoresizer/main.tf

@@ -0,0 +1,4 @@
+module "pvc_autoresizer" {
+  source = "./modules/pvc-autoresizer"
+  tier   = local.tiers.cluster
+}

stacks/pvc-autoresizer/modules/pvc-autoresizer/main.tf

@@ -0,0 +1,39 @@
+variable "tier" { type = string }
+
+resource "kubernetes_namespace" "pvc_autoresizer" {
+  metadata {
+    name = "pvc-autoresizer"
+    labels = {
+      tier = var.tier
+    }
+  }
+}
+
+resource "helm_release" "pvc_autoresizer" {
+  namespace        = kubernetes_namespace.pvc_autoresizer.metadata[0].name
+  create_namespace = false
+  name             = "pvc-autoresizer"
+  atomic           = true
+  timeout          = 300
+
+  repository = "https://topolvm.github.io/pvc-autoresizer"
+  chart      = "pvc-autoresizer"
+
+  values = [yamlencode({
+    controller = {
+      args = {
+        prometheusURL = "http://prometheus-server.monitoring.svc.cluster.local:80"
+        interval      = "10m"
+      }
+      resources = {
+        requests = {
+          memory = "64Mi"
+          cpu    = "10m"
+        }
+        limits = {
+          memory = "128Mi"
+        }
+      }
+    }
+  })]
+}

stacks/pvc-autoresizer/terragrunt.hcl

@@ -0,0 +1,8 @@
+include "root" {
+  path = find_in_parent_folders()
+}
+
+dependency "infra" {
+  config_path  = "../infra"
+  skip_outputs = true
+}

stacks/redis/modules/redis/main.tf

@@ -61,6 +61,11 @@ resource "helm_release" "redis" {
         enabled      = true
         storageClass = "proxmox-lvm"
         size         = "2Gi"
+        annotations = {
+          "resize.topolvm.io/threshold"     = "80%"
+          "resize.topolvm.io/increase"      = "50%"
+          "resize.topolvm.io/storage_limit" = "10Gi"
+        }
       }
 
       resources = {
@@ -81,6 +86,11 @@ resource "helm_release" "redis" {
         enabled      = true
         storageClass = "proxmox-lvm"
         size         = "2Gi"
+        annotations = {
+          "resize.topolvm.io/threshold"     = "80%"
+          "resize.topolvm.io/increase"      = "50%"
+          "resize.topolvm.io/storage_limit" = "10Gi"
+        }
       }
 
       resources = {

stacks/vaultwarden/modules/vaultwarden/main.tf

@@ -24,6 +24,11 @@ resource "kubernetes_persistent_volume_claim" "vaultwarden_data" {
   metadata {
     name      = "vaultwarden-data-proxmox"
     namespace = kubernetes_namespace.vaultwarden.metadata[0].name
+    annotations = {
+      "resize.topolvm.io/threshold"     = "80%"
+      "resize.topolvm.io/increase"      = "100%"
+      "resize.topolvm.io/storage_limit" = "5Gi"
+    }
   }
   spec {
     access_modes       = ["ReadWriteOnce"]