18426 Fix count of failed services in systemd service summary

SUP-24508

In the 'systemd service summary', failed systemd services were displayed
as such, even if they had been disabled on the system or set to 'ignore'
by the user.
This led to the service summary being misinterpreted according to the
set state, due to failed, but disabled or ignored, systemd services were
not triggering a CRIT state in the systemd service summary.

Now, disabled or ignored 'failed' systemd services are not counted as
failed services.

Change-Id: Ib3f36182a321934b811798a3f2ec8d22d2bacd7e

Author: otAAAh

.werks/18462.md

@@ -0,0 +1,20 @@
+[//]: # (werk v2)
+# Fix count of failed services in systemd service summary
+
+key        | value
+---------- | ---
+date       | 2025-07-24T14:21:29+00:00
+version    | 2.4.0p9
+class      | fix
+edition    | cre
+component  | checks
+level      | 1
+compatible | yes
+
+In the 'systemd service summary', failed systemd services were displayed as such,
+even if they had been disabled on the system or set to 'ignore' by the user.
+This led to the service summary being misinterpreted according to the set state,
+due to failed, but disabled or ignored, systemd services were not triggering a
+CRIT state in the systemd service summary.
+
+Now, disabled or ignored 'failed' systemd services are not counted as failed services.

cmk/plugins/collection/agent_based/systemd_units.py

@@ -765,15 +765,17 @@ def check_systemd_units_summary(
     services_organised = _services_split(units, blacklist)
     yield Result(state=State.OK, summary=f"Disabled: {len(services_organised['disabled']):d}")
 
+    sum_failed = sum(
+        s.active_status == "failed"
+        for s in units
+        if s not in services_organised["excluded"] and s not in services_organised["disabled"]
+    )
+
     yield Result(
         state=State(params["states"].get("failed", params["states_default"]))
-        if sum(
-            s.active_status == "failed"
-            for s in units
-            if s not in services_organised["excluded"] and s not in services_organised["disabled"]
-        )
+        if sum_failed
         else State.OK,
-        summary=f"Failed: {sum(s.active_status == 'failed' for s in units)}",
+        summary=f"Failed: {sum_failed}",
     )
 
     included_template = "{count:d} {unit_type} {status} ({service_text})"

tests/unit/cmk/plugins/collection/agent_based/test_systemd_units.py

@@ -1385,7 +1385,7 @@ def test_check_systemd_units_sockets(
             [
                 Result(state=State.OK, summary="Total: 1"),
                 Result(state=State.OK, summary="Disabled: 0"),
-                Result(state=State.OK, summary="Failed: 1"),
+                Result(state=State.OK, summary="Failed: 0"),
                 Result(state=State.OK, notice="Ignored: 1"),
             ],
             id="Failed, but ignored service",
@@ -1426,7 +1426,7 @@ def test_check_systemd_units_sockets(
             [
                 Result(state=State.OK, summary="Total: 2"),
                 Result(state=State.OK, summary="Disabled: 0"),
-                Result(state=State.CRIT, summary="Failed: 2"),
+                Result(state=State.CRIT, summary="Failed: 1"),
                 Result(
                     state=State.CRIT,
                     summary="1 service failed (zfs-import@fgprs\\x2dpbs02\\x2dpool1\\x2d100)",
@@ -1461,7 +1461,7 @@ def test_check_systemd_units_sockets(
             [
                 Result(state=State.OK, summary="Total: 1"),
                 Result(state=State.OK, summary="Disabled: 1"),
-                Result(state=State.OK, summary="Failed: 1"),
+                Result(state=State.OK, summary="Failed: 0"),
             ],
             id="One failed, but disabled",
         ),