grafana: make alerts better for fux

resources/chaosknoten/grafana/docker_compose/prometheus_alerts-fux.rules.yaml

@@ -0,0 +1,39 @@
+groups:
+  - name: Generic
+    rules:
+      - alert: HostJobFlaky
+        expr: group by(host, job) (changes(up{org="fux", job!="integrations/unix"}[24h]) > 5)
+        for: 0m
+        labels:
+          severity: info
+        annotations:
+          summary: Job {{ $labels.job }} flaky on (host {{ $labels.instance }})
+          description: "The job {{ $labels.job }} on target: {{ labels.host }} has been flaky over the last 24 hours.\n VALUE = {{ $value }}"
+  - name: SNMP
+    rules:
+      - alert: SnmpTargetMissing
+        expr: up{job=~".*snmp|SNMP.*"} == 0
+        for: 15m
+        labels:
+          severity: critical
+        annotations:
+          summary: SNMP target missing (instance {{ $labels.instance }})
+          description: "A SNMP target has disappeared for more the 15 min.\n  VALUE = {{ $value }}"
+  - name: DHCP
+    rules:
+      - alert: DhcpFuxSharedFailed
+        expr: script_success{script="check_dhcp_fux_shared"} == 0
+        for: 0m
+        labels:
+          severity: critical
+        annotations:
+          summary: DHCP for Fux Shared stoped working
+          description: "No DHCP lease for the Fux Shared range was received"
+      - alert: DhcpFuxAdminFailed
+        expr: script_success{script_success="check_dhcp_fux_admin"} == 0
+        for: 0m
+        labels:
+          severity: critical
+        annotations:
+          summary: DHCP for Fux Admin stoped working
+          description: "No DHCP lease for the Fux Admin range was received"