From d8a54e104191ba62c6be5b67ed333e757f2abdef Mon Sep 17 00:00:00 2001
From: Ilja Weis <Ilja.Weis@nexinto.com>
Date: Thu, 25 Jan 2018 17:25:55 +0100
Subject: [PATCH] fix node check

---
 check_kubernetes.go      | 39 +++++++++++++++++++++++++++++++++++++--
 check_kubernetes_test.go | 22 ++++++++++++++++++++++
 2 files changed, 59 insertions(+), 2 deletions(-)

diff --git a/check_kubernetes.go b/check_kubernetes.go
index fc34991..bc4b275 100644
--- a/check_kubernetes.go
+++ b/check_kubernetes.go
@@ -252,6 +252,10 @@ func checkNode(name string, kube kubernetes.Interface) (nrpe.Result, string) {
 
 	nosched := node.Spec.Unschedulable
 	ready := false
+	unknown := true
+
+	resourceTroubleMsg := ""
+	resourceTrouble := false
 
 	if len(node.Status.Conditions) < 1 {
 		return nrpe.UNKNOWN, "node in unknown state"
@@ -260,14 +264,41 @@ func checkNode(name string, kube kubernetes.Interface) (nrpe.Result, string) {
 	for _, cond := range node.Status.Conditions {
 		switch cond.Type {
 		case corev1.NodeReady:
+			unknown = false
 			if cond.Status == corev1.ConditionTrue {
 				ready = true
 			}
-		default: // invalid value for Type
-			return nrpe.UNKNOWN, "node in unknown state (invalid condition)"
+		case corev1.NodeOutOfDisk:
+			if cond.Status == corev1.ConditionTrue {
+				resourceTrouble = true
+				resourceTroubleMsg = resourceTroubleMsg + "out of disk "
+			}
+		case corev1.NodeDiskPressure:
+			if cond.Status == corev1.ConditionTrue {
+				resourceTrouble = true
+				resourceTroubleMsg = resourceTroubleMsg + "has disk pressure "
+			}
+		case corev1.NodeMemoryPressure:
+			if cond.Status == corev1.ConditionTrue {
+				resourceTrouble = true
+				resourceTroubleMsg = resourceTroubleMsg + "has memory pressure "
+			}
+		case corev1.NodeNetworkUnavailable:
+			if cond.Status == corev1.ConditionTrue {
+				resourceTrouble = true
+				resourceTroubleMsg = resourceTroubleMsg + "network unavailable "
+			}
 		}
 	}
 
+	if unknown {
+		return nrpe.UNKNOWN, "node in unknown state (invalid condition)"
+	}
+
+	if ready && resourceTrouble {
+		return nrpe.WARNING, "node ready but hits resource limits ( " + resourceTroubleMsg + ")"
+	}
+
 	if ready && nosched {
 		return nrpe.WARNING, "node ready but no scheduling allowed"
 	}
@@ -276,6 +307,10 @@ func checkNode(name string, kube kubernetes.Interface) (nrpe.Result, string) {
 		return nrpe.OK, "node ready"
 	}
 
+	if !ready && resourceTrouble {
+		return nrpe.CRITICAL, "node not ready ( " + resourceTroubleMsg + ")"
+	}
+
 	return nrpe.CRITICAL, "node not ready"
 }
 
diff --git a/check_kubernetes_test.go b/check_kubernetes_test.go
index 40e65a6..a14a399 100644
--- a/check_kubernetes_test.go
+++ b/check_kubernetes_test.go
@@ -462,6 +462,28 @@ func TestNode(t *testing.T) {
 			result:  nrpe.UNKNOWN,
 			message: "unknown",
 		},
+		{
+			node: corev1.Node{
+				ObjectMeta: metav1.ObjectMeta{Name: "foo10"},
+				Status: corev1.NodeStatus{Conditions: []corev1.NodeCondition{
+					{Type: corev1.NodeReady, Status: corev1.ConditionTrue},
+					{Type: corev1.NodeOutOfDisk, Status: corev1.ConditionFalse}}},
+			},
+			name:    "Ready",
+			result:  nrpe.OK,
+			message: "ready",
+		},
+		{
+			node: corev1.Node{
+				ObjectMeta: metav1.ObjectMeta{Name: "foo11"},
+				Status: corev1.NodeStatus{Conditions: []corev1.NodeCondition{
+					{Type: corev1.NodeReady, Status: corev1.ConditionTrue},
+					{Type: corev1.NodeOutOfDisk, Status: corev1.ConditionTrue}}},
+			},
+			name:    "OutOfDisk",
+			result:  nrpe.WARNING,
+			message: "disk",
+		},
 	}
 
 	for _, test := range tests {