Make PortalIP alloc HA

* Add an allocator which saves state in etcd
* Perform PortalIP allocation check on startup and periodically afterwards

Also expose methods in master for downstream components to handle IP allocation
/ master registration themselves.

pkg/api/v1/register.go

@@ -64,6 +64,7 @@ func init() {
 		&ComponentStatus{},
 		&ComponentStatusList{},
 		&SerializedReference{},
+		&RangeAllocation{},
 	)
 	// Legacy names are supported
 	api.Scheme.AddKnownTypeWithName("v1", "Minion", &Node{})
@@ -108,3 +109,4 @@ func (*PodProxyOptions) IsAnAPIObject()           {}
 func (*ComponentStatus) IsAnAPIObject()           {}
 func (*ComponentStatusList) IsAnAPIObject()       {}
 func (*SerializedReference) IsAnAPIObject()       {}
+func (*RangeAllocation) IsAnAPIObject()           {}

pkg/api/v1/types.go

@@ -1780,3 +1780,12 @@ type SELinuxOptions struct {
 	// SELinux level label.
 	Level string `json:"level,omitempty" description:"the level label to apply to the container"`
 }
+
+// RangeAllocation is not a public type
+type RangeAllocation struct {
+	TypeMeta   `json:",inline"`
+	ObjectMeta `json:"metadata,omitempty" description:"standard list metadata; see http://docs.k8s.io/api-conventions.md#metadata"`
+
+	Range string `json:"range" description:"a range string that identifies the range represented by 'data'; required"`
+	Data  []byte `json:"data" description:"a bit array containing all allocated addresses in the previous segment"`
+}