Check CloudAgent reachability in caph liveness probe (#266)

* Init commit: Check cloudagent reachability in liveness probe

* Take the liveness probe values are arguments to the binary and default those values

* Changes post merge conflict

* Remove exponential backoff, liveness probe parameters should be good enough

* Revert image change

* Remove unused parameters

---------

Co-authored-by: Pavan Neerudu <[email protected]>

Author: PavanNeerudu

cmd/manager/main.go

@@ -30,6 +30,7 @@ import (
 
 	// +kubebuilder:scaffold:imports
 
+	"github.com/microsoft/cluster-api-provider-azurestackhci/pkg/network"
 	"github.com/spf13/pflag"
 	"k8s.io/apimachinery/pkg/runtime"
 	clientgoscheme "k8s.io/client-go/kubernetes/scheme"
@@ -42,6 +43,7 @@ import (
 	ctrl "sigs.k8s.io/controller-runtime"
 	"sigs.k8s.io/controller-runtime/pkg/controller"
 	"sigs.k8s.io/controller-runtime/pkg/healthz"
+	ctrlmgr "sigs.k8s.io/controller-runtime/pkg/manager"
 
 	"github.com/microsoft/cluster-api-provider-azurestackhci/controllers"
 )
@@ -253,19 +255,32 @@ func main() {
 		os.Exit(1)
 	}
 
+	// Setup Health checks
+	setupChecks(mgr)
+
+	setupLog.Info("starting manager")
+	if err := mgr.Start(ctrl.SetupSignalHandler()); err != nil {
+		setupLog.Error(err, "problem running manager")
+		os.Exit(1)
+	}
+}
+
+func setupChecks(mgr ctrlmgr.Manager) {
 	if err := mgr.AddReadyzCheck("ping", healthz.Ping); err != nil {
 		setupLog.Error(err, "unable to create ready check")
 		os.Exit(1)
 	}
 
-	if err := mgr.AddHealthzCheck("ping", healthz.Ping); err != nil {
-		setupLog.Error(err, "unable to create health check")
+	// Get the cloudagent fqdn
+	cloudAgentFqdn := os.Getenv("AZURESTACKHCI_CLOUDAGENT_FQDN")
+	if cloudAgentFqdn == "" {
+		setupLog.Error(nil, "AZURESTACKHCI_CLOUDAGENT_FQDN is not set")
 		os.Exit(1)
 	}
 
-	setupLog.Info("starting manager")
-	if err := mgr.Start(ctrl.SetupSignalHandler()); err != nil {
-		setupLog.Error(err, "problem running manager")
+	cloudAgentAddress := cloudAgentFqdn + ":55000"
+	if err := mgr.AddHealthzCheck("ping", network.EndpointChecker(cloudAgentAddress)); err != nil {
+		setupLog.Error(err, "unable to create health check")
 		os.Exit(1)
 	}
 }

pkg/network/network.go

@@ -0,0 +1,23 @@
+package network
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"time"
+
+	"sigs.k8s.io/controller-runtime/pkg/healthz"
+)
+
+func EndpointChecker(targetIPAddress string) healthz.Checker {
+	return func(req *http.Request) error {
+		dialTimeout := 1 * time.Second
+
+		_, err := net.DialTimeout("tcp", targetIPAddress, dialTimeout)
+		if err != nil {
+			return fmt.Errorf("failed to dial: %v", err)
+		}
+
+		return nil
+	}
+}