diff --git a/etcdserver/etcdhttp/capability.go b/etcdserver/etcdhttp/capability.go
index 75d75a905..3397e9a9a 100644
--- a/etcdserver/etcdhttp/capability.go
+++ b/etcdserver/etcdhttp/capability.go
@@ -22,6 +22,7 @@ var (
 	// the base capabilities is the set of capability 2.0 supports.
 	capabilityMaps = map[string]map[capability]bool{
 		"2.1.0": {authCapability: true},
+		"2.2.0": {authCapability: true},
 	}
 
 	enableMapMu sync.Mutex