[collectd/systemd] deprecate the collectd/systemd monitor (#7205)

Author: atoulme

.chloggen/deprecate_systemd.yaml

@@ -0,0 +1,17 @@
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: deprecation
+
+# The name of the component, or a single word describing the area of concern, (e.g. crosslink)
+component: collectd/systemd
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Deprecate the collectd/systemd monitor
+
+# One or more tracking issues related to the change
+issues: [7205]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext: |
+  Please use the [systemd receiver](https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/main/receiver/systemdreceiver/README.md) instead.

internal/signalfx-agent/pkg/monitors/collectd/systemd/metadata.yaml

@@ -7,7 +7,8 @@ monitors:
       description: The name of the collectd plugin. Facilitates filtering operations
         in the SignalFx app
   doc: |
-    This [SignalFx Smart Agent](https://github.com/signalfx/signalfx-agent) monitor collects metrics about the state of
+    **This monitor is deprecated and will removed on or after April 2026. Please use the systemd receiver instead**
+    This monitor collects metrics about the state of
     configured systemd services using the [collectd-systemd](https://github.com/signalfx/collectd-systemd)
     plugin. A service is in the state that a metric represents if the metric value is 1 and not in that state if the
     metric value is 0. The name of the service that the metric is reporiting about is assigned to dimension

internal/signalfx-agent/pkg/monitors/collectd/systemd/systemd.go

@@ -93,5 +93,6 @@ func (m *Monitor) Configure(conf *Config) error {
 			"ServiceStates": serviceStates,
 		},
 	}
+	m.Logger().Warn("[NOTICE] The collectd/systemd monitor is deprecated and will be removed on or after April 2026. Please use the systemdreceiver instead.")
 	return m.PyMonitor.Configure(conf)
 }