Update README

Signed-off-by: Vitaly Zhuravlev <[email protected]>

Author: v-zhuravlev

docs/node-mixin/README.md

@@ -4,7 +4,7 @@ _This is a work in progress. We aim for it to become a good role model for alert
 and dashboards eventually, but it is not quite there yet._
 
 The Node Mixin is a set of configurable, reusable, and extensible alerts and
-dashboards based on the metrics exported by the Node Exporter. The mixin creates
+dashboards based on the metrics exported by the Node Exporter and logs by Loki(optional). The mixin creates
 recording and alerting rules for Prometheus and suitable dashboard descriptions
 for Grafana.
 
@@ -40,3 +40,47 @@ the previously generated `node_rules.yaml`.
 For more advanced uses of mixins, see
 https://github.com/monitoring-mixins/docs.
 
+## Loki Logs configuration
+
+To enable logs support in Node Mixin, enable them in config.libsonnet first:
+
+```
+{
+  _config+:: {
+    enableLokiLogs: true,
+  },
+}
+
+```
+
+then run
+```bash
+$ make build
+```
+
+This would generate extra Logs row on dashboards.
+
+For proper logs correlation, you need to make sure that `job` and `instance` labels values match for both node_exporter metrics and logs, collected by [Promtail](https://grafana.com/docs/loki/latest/clients/promtail/) or [Grafana Agent](https://grafana.com/docs/grafana-cloud/agent/).
+
+To scrape system logs, the following promtail config snippet can be used for `job=integrations/node` and `instance=host-01`:
+
+```yaml
+configs:
+  - name: integrations
+    scrape_configs:
+    - job_name: integrations/node_exporter_journal_scrape
+      journal:
+        max_age: 24h
+        labels:
+          instance: host-01
+          job: integrations/node
+      relabel_configs:
+      - source_labels: ['__journal__systemd_unit']
+        target_label: 'unit'
+      - source_labels: ['__journal__boot_id']
+        target_label: 'boot_id'
+      - source_labels: ['__journal__transport']
+        target_label: 'transport'
+      - source_labels: ['__journal_priority_keyword']
+        target_label: 'level'
+```