diff --git a/pkg/morph/client/netmap/update_state.go b/pkg/morph/client/netmap/update_state.go
index 1b860ffe..44a404d0 100644
--- a/pkg/morph/client/netmap/update_state.go
+++ b/pkg/morph/client/netmap/update_state.go
@@ -7,11 +7,17 @@ import (
 	"github.com/nspcc-dev/neofs-node/pkg/morph/client"
 )
 
+// TODO: enum can become redundant after neofs-contract#270
+const (
+	stateOffline int8 = iota
+	stateOnline
+)
+
 // UpdatePeerPrm groups parameters of UpdatePeerState operation.
 type UpdatePeerPrm struct {
 	key []byte
 
-	online bool
+	state int8 // state enum value
 
 	client.InvokePrmOptional
 }
@@ -21,9 +27,11 @@ func (u *UpdatePeerPrm) SetKey(key []byte) {
 	u.key = key
 }
 
-// SetState sets node state.
+// SetOnline marks node to be switched into "online" state.
+//
+// Zero UpdatePeerPrm marks node as "offline".
 func (u *UpdatePeerPrm) SetOnline() {
-	u.online = true
+	u.state = stateOnline
 }
 
 // UpdatePeerState changes peer status through Netmap contract call.
@@ -37,8 +45,14 @@ func (c *Client) UpdatePeerState(p UpdatePeerPrm) error {
 		method += "IR"
 	}
 
-	state := netmap.OfflineState
-	if p.online {
+	state := netmap.OfflineState // pre-assign since type of value is unexported
+
+	switch p.state {
+	default:
+		panic(fmt.Sprintf("unexpected node's state value %v", p.state))
+	case stateOffline:
+		// already set above
+	case stateOnline:
 		state = netmap.OnlineState
 	}
 
diff --git a/pkg/morph/event/netmap/update_peer.go b/pkg/morph/event/netmap/update_peer.go
index b96a932e..d83da6a5 100644
--- a/pkg/morph/event/netmap/update_peer.go
+++ b/pkg/morph/event/netmap/update_peer.go
@@ -12,10 +12,16 @@ import (
 	"github.com/nspcc-dev/neofs-node/pkg/morph/event"
 )
 
+// TODO: enum can become redundant after neofs-contract#270
+const (
+	_ int8 = iota
+	stateOnline
+)
+
 type UpdatePeer struct {
 	publicKey *keys.PublicKey
 
-	online bool
+	state int8 // state enum value
 
 	// For notary notifications only.
 	// Contains raw transactions of notary request.
@@ -26,7 +32,7 @@ type UpdatePeer struct {
 func (UpdatePeer) MorphEvent() {}
 
 func (s UpdatePeer) Online() bool {
-	return s.online
+	return s.state == stateOnline
 }
 
 func (s UpdatePeer) PublicKey() *keys.PublicKey {
@@ -78,7 +84,7 @@ func ParseUpdatePeer(e *state.ContainedNotificationEvent) (event.Event, error) {
 		return nil, fmt.Errorf("unsupported node state %d", st)
 	case int64(netmap.OfflineState):
 	case int64(netmap.OnlineState):
-		ev.online = true
+		ev.state = stateOnline
 	}
 
 	return ev, nil
diff --git a/pkg/morph/event/netmap/update_peer_notary.go b/pkg/morph/event/netmap/update_peer_notary.go
index 8dc22bfc..1c1b8b36 100644
--- a/pkg/morph/event/netmap/update_peer_notary.go
+++ b/pkg/morph/event/netmap/update_peer_notary.go
@@ -66,7 +66,7 @@ func ParseUpdatePeerNotary(ne event.NotaryEvent) (event.Event, error) {
 				return nil, fmt.Errorf("unsupported node state %d", err)
 			case v2netmap.Offline:
 			case v2netmap.Online:
-				ev.online = true
+				ev.state = stateOnline
 			}
 
 			fieldNum++
diff --git a/pkg/morph/event/netmap/update_peer_test.go b/pkg/morph/event/netmap/update_peer_test.go
index aa397be7..e45e99cb 100644
--- a/pkg/morph/event/netmap/update_peer_test.go
+++ b/pkg/morph/event/netmap/update_peer_test.go
@@ -51,7 +51,7 @@ func TestParseUpdatePeer(t *testing.T) {
 
 		require.Equal(t, UpdatePeer{
 			publicKey: publicKey,
-			online:    true,
+			state:     stateOnline,
 		}, ev)
 	})
 }