Merge pull request #2004 from russellb/schedulable-masters

scheduler: Use schedulable masters if no compute hosts defined.

pkg/asset/manifests/scheduler.go

@@ -5,9 +5,11 @@ import (
 
 	"github.com/ghodss/yaml"
 	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
 
 	configv1 "github.com/openshift/api/config/v1"
 	"github.com/openshift/installer/pkg/asset"
+	"github.com/openshift/installer/pkg/asset/installconfig"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
@@ -30,7 +32,9 @@ func (*Scheduler) Name() string {
 // Dependencies returns all of the dependencies directly needed to generate
 // the asset.
 func (*Scheduler) Dependencies() []asset.Asset {
-	return []asset.Asset{}
+	return []asset.Asset{
+		&installconfig.InstallConfig{},
+	}
 }
 
 // Generate generates the scheduler config and its CRD.
@@ -44,7 +48,29 @@ func (s *Scheduler) Generate(dependencies asset.Parents) error {
 			Name: "cluster",
 			// not namespaced
 		},
-		Spec: configv1.SchedulerSpec{},
+		Spec: configv1.SchedulerSpec{
+			MastersSchedulable: false,
+		},
+	}
+
+	installConfig := &installconfig.InstallConfig{}
+	dependencies.Get(installConfig)
+	computeReplicas := int64(0)
+	for _, pool := range installConfig.Config.Compute {
+		if pool.Replicas != nil {
+			computeReplicas += *pool.Replicas
+		}
+	}
+	if computeReplicas == 0 {
+		// A schedulable host is required for a successful install to complete.
+		// If the install config has 0 replicas for compute hosts, it's one of two cases:
+		//   1. An IPI deployment with no compute hosts.  The deployment can not succeed
+		//      without MastersSchedulable = true.
+		//   2. A UPI deployment.  The deployment may add compute hosts, but to ensure the
+		//      the highest probability of a successful deployment, we default to
+		//      schedulable masters.
+		logrus.Warningf("Making control-plane schedulable by setting MastersSchedulabe to true for Scheduler cluster settings")
+		config.Spec.MastersSchedulable = true
 	}
 
 	configData, err := yaml.Marshal(config)

pkg/types/validation/installconfig.go

@@ -8,7 +8,6 @@ import (
 
 	dockerref "github.com/containers/image/docker/reference"
 	"github.com/pkg/errors"
-	"github.com/sirupsen/logrus"
 	"k8s.io/apimachinery/pkg/util/validation/field"
 
 	"github.com/openshift/installer/pkg/types"
@@ -188,7 +187,6 @@ func validateControlPlane(platform *types.Platform, pool *types.MachinePool, fld
 func validateCompute(platform *types.Platform, pools []types.MachinePool, fldPath *field.Path) field.ErrorList {
 	allErrs := field.ErrorList{}
 	poolNames := map[string]bool{}
-	foundPositiveReplicas := false
 	for i, p := range pools {
 		poolFldPath := fldPath.Index(i)
 		if p.Name != "worker" {
@@ -198,14 +196,8 @@ func validateCompute(platform *types.Platform, pools []types.MachinePool, fldPat
 			allErrs = append(allErrs, field.Duplicate(poolFldPath.Child("name"), p.Name))
 		}
 		poolNames[p.Name] = true
-		if p.Replicas != nil && *p.Replicas > 0 {
-			foundPositiveReplicas = true
-		}
 		allErrs = append(allErrs, ValidateMachinePool(platform, &p, poolFldPath)...)
 	}
-	if !foundPositiveReplicas {
-		logrus.Warnf("There are no compute nodes specified. The cluster will not fully initialize without compute nodes.")
-	}
 	return allErrs
 }