diff --git a/internal/api/node.go b/internal/api/node.go
index 2f7a319..62c1e2a 100644
--- a/internal/api/node.go
+++ b/internal/api/node.go
@@ -23,6 +23,40 @@ type UpdateNodeStatesRequest struct {
 	Cluster string `json:"cluster" example:"fritz"`
 }
 
+// this routine assumes that only one of them applies per node
+func determineState(states []string) schema.NodeState {
+	for _, state := range states {
+		switch state {
+		case "allocated":
+			return schema.NodeStateAllocated
+		case "reserved":
+			return schema.NodeStateReserved
+		case "idle":
+			return schema.NodeStateIdle
+		case "down":
+			return schema.NodeStateDown
+		case "mixed":
+			return schema.NodeStateMixed
+		}
+	}
+
+	return schema.NodeStateUnknown
+}
+
+// updateNodeStates godoc
+// @summary     Deliver updated Slurm node states
+// @tags node
+// @description Returns a JSON-encoded list of users.
+// @description Required query-parameter defines if all users or only users with additional special roles are returned.
+// @produce     json
+// @param       request body UpdateNodeStatesRequest true "Request body containing nodes and their states"
+// @success     200     {array} api.SuccessResponse "Success"
+// @failure     400     {string} string             "Bad Request"
+// @failure     401     {string} string             "Unauthorized"
+// @failure     403     {string} string             "Forbidden"
+// @failure     500     {string} string             "Internal Server Error"
+// @security    ApiKeyAuth
+// @router      /api/nodestats/ [post]
 func (api *RestApi) updateNodeStates(rw http.ResponseWriter, r *http.Request) {
 	// Parse request body
 	req := UpdateNodeStatesRequest{}
@@ -33,9 +67,7 @@ func (api *RestApi) updateNodeStates(rw http.ResponseWriter, r *http.Request) {
 	repo := repository.GetNodeRepository()
 
 	for _, node := range req.Nodes {
-		state := schema.NodeStateUnknown
-		// TODO: Determine valid node state
+		state := determineState(node.States)
 		repo.UpdateNodeState(node.Name, req.Cluster, &state)
-
 	}
 }