casa/services/monitoring/deploy/alloy/node-scraper/helm-values.yaml

controller:
  nameOverride: "alloy-node-scrapper"
  volumes:
    extra:
      # requires host journal configuration storage = volatile
      - name: run-log-journal
        hostPath:
          path: /run/log/journal
      # Log scrapers (e.g., Alloy/Loki) read this ID from the journal metadata and use it to separate log streams per machine.
      - name: etc-machine-id
        hostPath:
          path: /etc/machine-id
      - name: rootfs
        hostPath:
          path: /
      - name: proc
        hostPath:
          path: /proc
      - name: sys
        hostPath:
          path: /sys
      - name: dev
        hostPath:
          path: /dev

  tolerations:
    - key: "node-role.kubernetes.io/control-plane"
      operator: "Exists"
      effect: "NoSchedule"
    - key: "infra.limbosolutions.com/dedicated"
      operator: "Exists"
      effect: "NoSchedule"

alloy:
  mounts:
    varlog: true  # Mounts /var/log from the host (persistent journal)
    extra:
      # requires host journal configuration storage = volatile
      - name: run-log-journal
        mountPath: /run/log/journal
        readOnly: true
      # required 
      - name: etc-machine-id
        mountPath: /etc/machine-id
        readOnly: true
      - name: rootfs
        mountPath: /host
        readOnly: true
      - name: proc
        mountPath: /host/proc
        readOnly: true
      - name: sys
        mountPath: /host/sys
        readOnly: true
      - name: dev
        mountPath: /host/dev
        readOnly: true 
  # https://grafana.com/docs/alloy/latest/collect/logs-in-kubernetes/
  configMap:
    content: |
      // ============================================
      // LOKI WRITE TARGET
      // ============================================
      loki.write "loki_srv" {
        endpoint {
          url = env("LOKI_URL")
        }
      }

      // ============================================
      // HOST JOURNALD SOURCE
      // ============================================

      // Read journald logs from the host
      loki.source.journal "journal" {
        max_age   = "24h"
        relabel_rules = discovery.relabel.host_journal.rules
        forward_to    = [loki.process.host_journal.receiver]
      }

      // ============================================
      // HOST JOURNALD RELABELING
      // ============================================

      // Convert journald metadata into Loki labels
      discovery.relabel "host_journal" {
        targets = []

        // Systemd unit name
        rule {
          source_labels = ["__journal__systemd_unit"]
          target_label  = "systemd_unit"
        }

        // Transport type (stdout, syslog, kernel, audit, etc.)
        rule {
          source_labels = ["__journal__transport"]
          target_label  = "journal_transport"
        }

        // Priority (info, warning, error)
        rule {
          source_labels = ["__journal_priority_keyword"]
          target_label  = "level"
        }
      }

      // ============================================
      // HOST JOURNALD PROCESSING
      // ============================================

      // Add static labels and forward journald logs to Loki
      loki.process "host_journal" {
        stage.static_labels {
          values = {
            cluster = env("CLUSTER_NAME"),
            host    = env("NODE_NAME"),
            zone    = env("ZONE"),
            job     = "journald",
            service_name = "journald",
          }
        }

        forward_to = [loki.write.loki_srv.receiver]
      }
      // ============================================
      // prometheus unix exporter
      // ============================================
      prometheus.exporter.unix "node_exporter" {
        rootfs_path = "/host"
        disable_collectors = ["ipvs", "btrfs", "infiniband", "xfs", "zfs"]
        enable_collectors = [
          "cpu",
          "meminfo",
          "vmstat",
          "loadavg",
          "filesystem",
          "netdev",
          "uname",
        ]

        filesystem {
          mount_points_exclude = "^/(dev|proc|sys|run/containerd/.+|var/lib/docker/.+|var/lib/kubelet/.+)($|/)"
          fs_types_exclude     = "^(autofs|binfmt_misc|bpf|cgroup2?|configfs|debugfs|devpts|devtmpfs|fusectl|hugetlbfs|iso9660|mqueue|nsfs|overlay|proc|procfs|pstore|rpc_pipefs|securityfs|selinuxfs|squashfs|sysfs|tracefs|erofs)$"
          mount_timeout        = "5s"
        }

        netclass {
          ignored_devices = "^(veth.*|cali.*|[a-f0-9]{15})$"
        }

        netdev {
          device_exclude = "^(veth.*|cali.*|[a-f0-9]{15})$"
        }
      }
    
      prometheus.scrape "node_exporter" {
        targets         = prometheus.exporter.unix.node_exporter.targets
        scrape_interval = "30s"

        forward_to = [prometheus.relabel.node_exporter.receiver]
      }

      prometheus.relabel "node_exporter" {

        rule {
          target_label = "instance"
          replacement  = env("NODE_IP") + ":9100"
        }

        rule {
          target_label = "nodename"
          replacement  = env("HOSTNAME")
        }

        rule {
          target_label = "node"
          replacement  = env("HOSTNAME")
        }

        rule {
          target_label = "kubernetes_node"
          replacement  = env("HOSTNAME")
        }

        rule {
          target_label = "cluster"
          replacement  = env("CLUSTER_NAME")
        }

        rule {
          target_label = "job"
          replacement  = env("JOB")
        }

        rule {

          target_label = "container"
          replacement  = env("CONTAINER")
        }
        rule {

          target_label = "NS"
          replacement  = env("NS")
        }

        rule {
          target_label = "pod"
          replacement  = env("POD")
        }

        rule {
          target_label = "service"
          replacement  = env("SERVICE")
        }

        forward_to = [prometheus.remote_write.metrics_service.receiver]

      }

      prometheus.remote_write "metrics_service" {

        endpoint {
          url = env("PROMETHEUS_URL")
        }

      }

  extraEnv:
    - name: NODE_NAME
      valueFrom:
        fieldRef:
          fieldPath: spec.nodeName
    - name: CLUSTER_NAME
      value: casa
    - name: JOB
      value: node-exporter
    - name: CONTAINER
      value: node-exporter
    - name: NS
      value: monitoring
    - name: POD
      value: alloy-node-scraper
    - name: SERVICE
      value: alloy-node-scraper
    - name: ZONE
      value: casa-vlan
    - name: LOKI_URL
      valueFrom:
        secretKeyRef:
          name: alloy-global
          key: loki_url
    - name: PROMETHEUS_URL
      valueFrom:
        secretKeyRef:
          name: alloy-global
          key: prometheus_url