add loki + promtail

templates/monitoring/loki.yaml.j2

@@ -0,0 +1,29 @@
+auth_enabled: false
+
+server:
+  http_listen_port: 3100
+
+common:
+  path_prefix: /loki
+  storage:
+    filesystem:
+      chunks_directory: /loki/chunks
+      rules_directory: /loki/rules
+  replication_factor: 1
+  ring:
+    kvstore:
+      store: inmemory
+
+schema_config:
+  configs:
+    - from: 2020-10-24
+      store: tsdb
+      object_store: filesystem
+      schema: v13
+      index:
+        prefix: index_
+        period: 24h
+
+storage_config:
+  filesystem:
+    directory: /loki/chunks

templates/monitoring/promtail.yaml.j2

@@ -0,0 +1,17 @@
+server:
+  http_listen_port: 9080
+
+positions:
+  filename: /tmp/positions.yaml
+
+clients:
+  - url: http://monitoring_loki:3100/loki/api/v1/push
+
+scrape_configs:
+  - job_name: system
+    static_configs:
+      - targets:
+          - localhost
+        labels:
+          job: varlogs
+          __path__: /var/log/**/*.log