groups:
  - name: ptp
    rules:
      - alert: PTPExporterDown
        expr: up{job=~"ptp-linux|ptp-nexus"} == 0
        for: 2m
        labels:
          severity: warning
        annotations:
          summary: "PTP exporter is unreachable on {{ $labels.instance }}"

      - alert: LinuxPTPScrapeFailed
        expr: ptp_exporter_scrape_success{stage!="ok"} == 0
        for: 2m
        labels:
          severity: warning
        annotations:
          summary: "linuxptp PMC scrape failed on {{ $labels.instance }}"

      - alert: PTPGrandmasterMissing
        expr: ptp_gm_present == 0
        for: 30s
        labels:
          severity: critical
        annotations:
          summary: "PTP grandmaster is not present on {{ $labels.instance }}"

      - alert: NexusPTPUnlocked
        expr: ptp_nexus_clock_locked == 0
        for: 30s
        labels:
          severity: critical
        annotations:
          summary: "Nexus PTP clock is not locked"

      # Start conservatively and tighten this after observing normal behavior.
      - alert: PTPMasterOffsetHigh
        expr: abs(ptp_master_offset_nanoseconds) > 1000
        for: 5m
        labels:
          severity: warning
        annotations:
          summary: "PTP offset exceeds 1 us on {{ $labels.instance }}"

      - alert: NexusPTPMasterOffsetHigh
        expr: abs(ptp_nexus_offset_from_master_nanoseconds) > 1000
        for: 5m
        labels:
          severity: warning
        annotations:
          summary: "Nexus PTP offset exceeds 1 us"