Enforce network config not including PrimaryNetworkID in `trackedSu…

…bnets` (#3336)

network/config.go

@@ -131,6 +131,7 @@ type Config struct {
 	BLSKey *bls.SecretKey `json:"-"`
 
 	// TrackedSubnets of the node.
+	// It must not include the primary network ID.
 	TrackedSubnets set.Set[ids.ID]    `json:"-"`
 	Beacons        validators.Manager `json:"-"`
 

network/network.go

@@ -51,10 +51,11 @@ const (
 var (
 	_ Network = (*network)(nil)
 
-	errNotValidator        = errors.New("node is not a validator")
-	errNotTracked          = errors.New("subnet is not tracked")
-	errExpectedProxy       = errors.New("expected proxy")
-	errExpectedTCPProtocol = errors.New("expected TCP protocol")
+	errNotValidator           = errors.New("node is not a validator")
+	errNotTracked             = errors.New("subnet is not tracked")
+	errExpectedProxy          = errors.New("expected proxy")
+	errExpectedTCPProtocol    = errors.New("expected TCP protocol")
+	errTrackingPrimaryNetwork = errors.New("cannot track primary network")
 )
 
 // Network defines the functionality of the networking library.
@@ -202,6 +203,10 @@ func NewNetwork(
 		}
 	}
 
+	if config.TrackedSubnets.Contains(constants.PrimaryNetworkID) {
+		return nil, errTrackingPrimaryNetwork
+	}
+
 	inboundMsgThrottler, err := throttling.NewInboundMsgThrottler(
 		log,
 		metricsRegisterer,