fix(cockpit): added extraDiscoveryRules (#5788)

Author: fleblay

pages/cockpit/how-to/send-logs-from-k8s-to-cockpit.mdx

@@ -63,7 +63,13 @@ podLogs:
   destinations: ["my-cockpit-logs"]
   volumeGatherSettings:
     onlyGatherNewLogLines: true
-
+  # Prevent collecting the collector own logs
+  extraDiscoveryRules: |
+    rule {
+      source_labels = ["__meta_kubernetes_pod_name"]
+      action = "drop"
+      regex = ".*alloy-logs.*"
+    }
 # An Alloy instance for collecting log data.
 alloy-logs:
   enabled: true
@@ -73,6 +79,12 @@ alloy-logs:
 alloy-singleton:
   enabled: true
 ```
+<Message type="tip">
+  The `PodLogs` feature automatically discovers and collects logs from all pods.
+In the configuration above, we excluded the logs from the pod responsible for log collection itself.
+
+If you want to exclude additional pods, you can add more drop rules in the `extraDiscoveryRules` section.
+</Message>
 
 <Message type="note">
  The template above is for sending logs to your Cockpit. You can also configure it to send metrics to Cockpit using this Helm chart.
@@ -146,4 +158,4 @@ You can also use Terraform/OpenTofu to manage and deploy Helm charts, providing
 7. Optionally, click the **Clock** icon on the top right corner of your screen and filter by time range.
 8. Click **Run query** to see your logs. An output similar to the following should display.
 
-<Lightbox image={image} alt="" />
+<Lightbox image={image} alt="" />