Configure QUIC fabric stream limits

agents/rap-node-agent/cmd/rap-node-agent/main.go

@@ -1095,7 +1095,7 @@ func startSyntheticMeshEndpoint(ctx context.Context, _ context.CancelFunc, cfg c
 		VPNFabricIngress:                  vpnFabricIngress,
 		VPNFabricSessionPeers:             vpnFabricSessionPeers,
 		VPNFabricTransport:                mesh.NewWebSocketFabricTransport(vpnFabricSessionPeers),
-		VPNFabricQUICTransport:            mesh.NewQUICFabricTransport(nil),
+		VPNFabricQUICTransport:            newVPNFabricQUICTransport(cfg),
 		VPNFabricSessionDialStats:         newVPNFabricSessionDialStats(),
 		VPNFabricEndpointObservations:     newVPNFabricEndpointObservationStore(identity.NodeID),
 		PeerEndpoints:                     copyStringMap(peerEndpoints),
@@ -1151,6 +1151,14 @@ func newVPNFabricIngress(meshState *syntheticMeshState, identity state.Identity,
 	return ingress
 }
 
+func newVPNFabricQUICTransport(cfg config.Config) *mesh.QUICFabricTransport {
+	transport := mesh.NewQUICFabricTransport(nil)
+	if cfg.VPNFabricQUICMaxStreamsPerConn > 0 {
+		transport.MaxStreamsPerConn = cfg.VPNFabricQUICMaxStreamsPerConn
+	}
+	return transport
+}
+
 func vpnruntimeAdaptivePolicy(policy *client.FabricServiceChannelAdaptivePolicy) vpnruntime.FabricServiceChannelAdaptivePolicy {
 	if policy == nil {
 		return vpnruntime.FabricServiceChannelAdaptivePolicy{}
@@ -1991,7 +1999,7 @@ func applyRefreshedSyntheticMeshConfig(ctx context.Context, cfg config.Config, i
 		}
 		meshState.VPNFabricSessionPeers = mesh.NewFabricSessionPeerManager()
 		meshState.VPNFabricTransport = mesh.NewWebSocketFabricTransport(meshState.VPNFabricSessionPeers)
-		meshState.VPNFabricQUICTransport = mesh.NewQUICFabricTransport(nil)
+		meshState.VPNFabricQUICTransport = newVPNFabricQUICTransport(cfg)
 	}
 	if meshState.VPNFabricSessionPeers == nil {
 		meshState.VPNFabricSessionPeers = mesh.NewFabricSessionPeerManager()
@@ -2000,7 +2008,9 @@ func applyRefreshedSyntheticMeshConfig(ctx context.Context, cfg config.Config, i
 		meshState.VPNFabricTransport = mesh.NewWebSocketFabricTransport(meshState.VPNFabricSessionPeers)
 	}
 	if meshState.VPNFabricQUICTransport == nil {
-		meshState.VPNFabricQUICTransport = mesh.NewQUICFabricTransport(nil)
+		meshState.VPNFabricQUICTransport = newVPNFabricQUICTransport(cfg)
+	} else if cfg.VPNFabricQUICMaxStreamsPerConn > 0 {
+		meshState.VPNFabricQUICTransport.MaxStreamsPerConn = cfg.VPNFabricQUICMaxStreamsPerConn
 	}
 	if meshState.VPNFabricSessionDialStats == nil {
 		meshState.VPNFabricSessionDialStats = newVPNFabricSessionDialStats()
@@ -2965,7 +2975,9 @@ func heartbeatPayload(cfg config.Config, identity state.Identity, meshState *syn
 				report["peer_sessions"] = meshState.VPNFabricSessionPeers.Snapshot()
 			}
 			if meshState != nil && meshState.VPNFabricQUICTransport != nil {
-				report["quic_sessions"] = meshState.VPNFabricQUICTransport.Snapshot()
+				quicSnapshot := meshState.VPNFabricQUICTransport.Snapshot()
+				report["quic_sessions"] = quicSnapshot
+				report["quic_max_streams_per_conn"] = meshState.VPNFabricQUICTransport.MaxStreamsPerConn
 			}
 			if meshState != nil && meshState.VPNFabricSessionDialStats != nil {
 				report["dial_stats"] = meshState.VPNFabricSessionDialStats.Report(observedAt)

agents/rap-node-agent/cmd/rap-node-agent/main_test.go

@@ -707,6 +707,7 @@ func TestHeartbeatPayloadIncludesMeshEndpointReport(t *testing.T) {
 		MeshProductionForwardingEnabled:  true,
 		MeshFabricSessionEnabled:         true,
 		VPNFabricSessionTransportEnabled: true,
+		VPNFabricQUICMaxStreamsPerConn:   24,
 		MeshQUICFabricEnabled:            true,
 		MeshQUICFabricListenAddr:         ":19443",
 	}, state.Identity{
@@ -714,7 +715,12 @@ func TestHeartbeatPayloadIncludesMeshEndpointReport(t *testing.T) {
 		NodeID:    "node-a",
 	}, &syntheticMeshState{
 		VPNFabricSessionPeers: mesh.NewFabricSessionPeerManager(),
-		QUICFabricListenAddr:  "127.0.0.1:19443",
+		VPNFabricQUICTransport: func() *mesh.QUICFabricTransport {
+			transport := mesh.NewQUICFabricTransport(nil)
+			transport.MaxStreamsPerConn = 24
+			return transport
+		}(),
+		QUICFabricListenAddr: "127.0.0.1:19443",
 	}, time.Date(2026, 4, 28, 12, 0, 0, 0, time.UTC))
 
 	report, ok := payload.Metadata["mesh_endpoint_report"].(map[string]any)
@@ -754,6 +760,8 @@ func TestHeartbeatPayloadIncludesMeshEndpointReport(t *testing.T) {
 		report["transport"] != "fabric_session_binary_frames" ||
 		report["peer_sessions"] == nil {
 		t.Fatalf("vpn fabric session report missing: %+v", payload.Metadata)
+	} else if report["quic_sessions"] == nil || report["quic_max_streams_per_conn"] != 24 {
+		t.Fatalf("vpn fabric quic session report missing: %+v", report)
 	}
 	if payload.Capabilities["vpn_fabric_endpoint_health_feedback"] != true {
 		t.Fatalf("vpn fabric endpoint health capability missing: %+v", payload.Capabilities)

agents/rap-node-agent/internal/config/config.go

@@ -30,6 +30,7 @@ type Config struct {
 	VPNFabricSessionTransportEnabled      bool
 	MeshQUICFabricEnabled                 bool
 	MeshQUICFabricListenAddr              string
+	VPNFabricQUICMaxStreamsPerConn        int
 	MeshProductionObservationSinkCapacity int
 	MeshListenAddr                        string
 	MeshListenPortMode                    string
@@ -71,6 +72,7 @@ func Load(args []string, env map[string]string) (Config, error) {
 	fs.BoolVar(&cfg.VPNFabricSessionTransportEnabled, "vpn-fabric-session-transport-enabled", getEnvBool(env, "RAP_VPN_FABRIC_SESSION_TRANSPORT_ENABLED", false), "Route VPN packet transport over persistent fabric session when explicitly enabled. Disabled by default.")
 	fs.BoolVar(&cfg.MeshQUICFabricEnabled, "mesh-quic-fabric-enabled", getEnvBool(env, "RAP_MESH_QUIC_FABRIC_ENABLED", false), "Enable QUIC/UDP fabric listener. Disabled by default.")
 	fs.StringVar(&cfg.MeshQUICFabricListenAddr, "mesh-quic-fabric-listen-addr", getEnv(env, "RAP_MESH_QUIC_FABRIC_LISTEN_ADDR", ""), "Listen address for QUIC/UDP fabric endpoint, for example :19443.")
+	fs.IntVar(&cfg.VPNFabricQUICMaxStreamsPerConn, "vpn-fabric-quic-max-streams-per-conn", getEnvInt(env, "RAP_VPN_FABRIC_QUIC_MAX_STREAMS_PER_CONN", 64), "Maximum logical fabric-session streams per cached VPN QUIC carrier connection.")
 	fs.IntVar(&cfg.MeshProductionObservationSinkCapacity, "mesh-production-observation-sink-capacity", getEnvSignedInt(env, "RAP_MESH_PRODUCTION_OBSERVATION_SINK_CAPACITY", 0), "Bounded local metadata-only production envelope observation sink capacity. Disabled when 0.")
 	fs.StringVar(&cfg.MeshListenAddr, "mesh-listen-addr", getEnv(env, "RAP_MESH_LISTEN_ADDR", ""), "Listen address for disabled-by-default C17E synthetic mesh HTTP endpoint.")
 	fs.StringVar(&cfg.MeshListenPortMode, "mesh-listen-port-mode", getEnv(env, "RAP_MESH_LISTEN_PORT_MODE", "manual"), "Mesh listen port behavior: manual, auto, or disabled.")
@@ -108,6 +110,9 @@ func Load(args []string, env map[string]string) (Config, error) {
 	cfg.MeshListenAddr = strings.TrimSpace(cfg.MeshListenAddr)
 	cfg.MeshQUICFabricListenAddr = strings.TrimSpace(cfg.MeshQUICFabricListenAddr)
 	cfg.MeshListenPortMode = strings.ToLower(strings.TrimSpace(cfg.MeshListenPortMode))
+	if cfg.VPNFabricQUICMaxStreamsPerConn <= 0 {
+		cfg.VPNFabricQUICMaxStreamsPerConn = 64
+	}
 	cfg.MeshAdvertiseEndpoint = strings.TrimRight(strings.TrimSpace(cfg.MeshAdvertiseEndpoint), "/")
 	cfg.MeshAdvertiseEndpointsJSON = strings.TrimSpace(cfg.MeshAdvertiseEndpointsJSON)
 	cfg.MeshAdvertiseTransport = strings.TrimSpace(cfg.MeshAdvertiseTransport)

agents/rap-node-agent/internal/config/config_test.go

@@ -24,6 +24,7 @@ func TestLoadConfigFromEnvAndArgs(t *testing.T) {
 		"RAP_VPN_FABRIC_SESSION_TRANSPORT_ENABLED":      "true",
 		"RAP_MESH_QUIC_FABRIC_ENABLED":                  "true",
 		"RAP_MESH_QUIC_FABRIC_LISTEN_ADDR":              ":19443",
+		"RAP_VPN_FABRIC_QUIC_MAX_STREAMS_PER_CONN":      "24",
 		"RAP_MESH_PRODUCTION_OBSERVATION_SINK_CAPACITY": "5",
 		"RAP_MESH_LISTEN_ADDR":                          "127.0.0.1:19001",
 		"RAP_MESH_LISTEN_PORT_MODE":                     "auto",
@@ -79,6 +80,9 @@ func TestLoadConfigFromEnvAndArgs(t *testing.T) {
 	if !cfg.MeshQUICFabricEnabled || cfg.MeshQUICFabricListenAddr != ":19443" {
 		t.Fatalf("unexpected QUIC fabric config: %+v", cfg)
 	}
+	if cfg.VPNFabricQUICMaxStreamsPerConn != 24 {
+		t.Fatalf("VPNFabricQUICMaxStreamsPerConn = %d, want 24", cfg.VPNFabricQUICMaxStreamsPerConn)
+	}
 	if cfg.MeshProductionObservationSinkCapacity != 5 {
 		t.Fatalf("MeshProductionObservationSinkCapacity = %d, want 5", cfg.MeshProductionObservationSinkCapacity)
 	}

agents/rap-node-agent/internal/hostagent/config.go

@@ -33,6 +33,7 @@ type RuntimeConfig struct {
 	VPNFabricSessionTransportEnabled bool
 	MeshQUICFabricEnabled            bool
 	MeshQUICFabricListenAddr         string
+	VPNFabricQUICMaxStreamsPerConn   int
 	MeshListenAddr                   string
 	MeshListenPortMode               string
 	MeshListenAutoPortStart          int
@@ -66,6 +67,9 @@ func (cfg RuntimeConfig) Normalize() RuntimeConfig {
 	cfg.RestartPolicy = firstNonEmpty(cfg.RestartPolicy, "unless-stopped")
 	cfg.MeshListenAddr = strings.TrimSpace(cfg.MeshListenAddr)
 	cfg.MeshQUICFabricListenAddr = strings.TrimSpace(cfg.MeshQUICFabricListenAddr)
+	if cfg.VPNFabricQUICMaxStreamsPerConn <= 0 {
+		cfg.VPNFabricQUICMaxStreamsPerConn = 64
+	}
 	cfg.MeshListenPortMode = strings.ToLower(strings.TrimSpace(cfg.MeshListenPortMode))
 	cfg.MeshAdvertiseEndpoint = strings.TrimRight(strings.TrimSpace(cfg.MeshAdvertiseEndpoint), "/")
 	cfg.MeshAdvertiseEndpointsJSON = strings.TrimSpace(cfg.MeshAdvertiseEndpointsJSON)

agents/rap-node-agent/internal/hostagent/docker.go

@@ -267,6 +267,7 @@ func NodeAgentEnvWithStateDir(cfg RuntimeConfig, stateDir string) []string {
 		"RAP_MESH_FABRIC_SESSION_ENABLED=" + boolString(cfg.MeshFabricSessionEnabled),
 		"RAP_VPN_FABRIC_SESSION_TRANSPORT_ENABLED=" + boolString(cfg.VPNFabricSessionTransportEnabled),
 		"RAP_MESH_QUIC_FABRIC_ENABLED=" + boolString(cfg.MeshQUICFabricEnabled),
+		"RAP_VPN_FABRIC_QUIC_MAX_STREAMS_PER_CONN=" + strconv.Itoa(cfg.VPNFabricQUICMaxStreamsPerConn),
 	}
 	if cfg.JoinToken != "" {
 		env = append(env, "RAP_JOIN_TOKEN="+cfg.JoinToken)

agents/rap-node-agent/internal/hostagent/linux.go

@@ -76,6 +76,7 @@ func LinuxInstallConfigFromProfile(profile LinuxInstallProfile) LinuxInstallConf
 			VPNFabricSessionTransportEnabled: profile.VPNFabricSessionTransportEnabled,
 			MeshQUICFabricEnabled:            profile.MeshQUICFabricEnabled,
 			MeshQUICFabricListenAddr:         profile.MeshQUICFabricListenAddr,
+			VPNFabricQUICMaxStreamsPerConn:   profile.VPNFabricQUICMaxStreamsPerConn,
 			MeshListenAddr:                   profile.MeshListenAddr,
 			MeshListenPortMode:               profile.MeshListenPortMode,
 			MeshListenAutoPortStart:          profile.MeshListenAutoPortStart,

agents/rap-node-agent/internal/hostagent/profile.go

@@ -34,6 +34,7 @@ type DockerInstallProfile struct {
 	VPNFabricSessionTransportEnabled  bool            `json:"vpn_fabric_session_transport_enabled"`
 	MeshQUICFabricEnabled             bool            `json:"mesh_quic_fabric_enabled"`
 	MeshQUICFabricListenAddr          string          `json:"mesh_quic_fabric_listen_addr"`
+	VPNFabricQUICMaxStreamsPerConn    int             `json:"vpn_fabric_quic_max_streams_per_conn"`
 	MeshListenAddr                    string          `json:"mesh_listen_addr"`
 	MeshListenPortMode                string          `json:"mesh_listen_port_mode"`
 	MeshListenAutoPortStart           int             `json:"mesh_listen_auto_port_start"`
@@ -80,6 +81,7 @@ type WindowsInstallProfile struct {
 	VPNFabricSessionTransportEnabled  bool            `json:"vpn_fabric_session_transport_enabled"`
 	MeshQUICFabricEnabled             bool            `json:"mesh_quic_fabric_enabled"`
 	MeshQUICFabricListenAddr          string          `json:"mesh_quic_fabric_listen_addr"`
+	VPNFabricQUICMaxStreamsPerConn    int             `json:"vpn_fabric_quic_max_streams_per_conn"`
 	MeshListenAddr                    string          `json:"mesh_listen_addr"`
 	MeshListenPortMode                string          `json:"mesh_listen_port_mode"`
 	MeshListenAutoPortStart           int             `json:"mesh_listen_auto_port_start"`
@@ -116,6 +118,7 @@ type LinuxInstallProfile struct {
 	VPNFabricSessionTransportEnabled  bool            `json:"vpn_fabric_session_transport_enabled"`
 	MeshQUICFabricEnabled             bool            `json:"mesh_quic_fabric_enabled"`
 	MeshQUICFabricListenAddr          string          `json:"mesh_quic_fabric_listen_addr"`
+	VPNFabricQUICMaxStreamsPerConn    int             `json:"vpn_fabric_quic_max_streams_per_conn"`
 	MeshListenAddr                    string          `json:"mesh_listen_addr"`
 	MeshListenPortMode                string          `json:"mesh_listen_port_mode"`
 	MeshListenAutoPortStart           int             `json:"mesh_listen_auto_port_start"`
@@ -297,6 +300,7 @@ func RuntimeConfigFromProfile(profile DockerInstallProfile) RuntimeConfig {
 		VPNFabricSessionTransportEnabled: profile.VPNFabricSessionTransportEnabled,
 		MeshQUICFabricEnabled:            profile.MeshQUICFabricEnabled,
 		MeshQUICFabricListenAddr:         profile.MeshQUICFabricListenAddr,
+		VPNFabricQUICMaxStreamsPerConn:   profile.VPNFabricQUICMaxStreamsPerConn,
 		MeshListenAddr:                   profile.MeshListenAddr,
 		MeshListenPortMode:               profile.MeshListenPortMode,
 		MeshListenAutoPortStart:          profile.MeshListenAutoPortStart,

agents/rap-node-agent/internal/hostagent/update.go

@@ -598,6 +598,7 @@ func (m DockerManager) runtimeConfigFromContainer(ctx context.Context, runner Co
 		VPNFabricSessionTransportEnabled: parseBool(env["RAP_VPN_FABRIC_SESSION_TRANSPORT_ENABLED"]),
 		MeshQUICFabricEnabled:            parseBool(env["RAP_MESH_QUIC_FABRIC_ENABLED"]),
 		MeshQUICFabricListenAddr:         env["RAP_MESH_QUIC_FABRIC_LISTEN_ADDR"],
+		VPNFabricQUICMaxStreamsPerConn:   parseInt(env["RAP_VPN_FABRIC_QUIC_MAX_STREAMS_PER_CONN"]),
 		MeshListenAddr:                   env["RAP_MESH_LISTEN_ADDR"],
 		MeshListenPortMode:               env["RAP_MESH_LISTEN_PORT_MODE"],
 		MeshListenAutoPortStart:          parseInt(env["RAP_MESH_LISTEN_AUTO_PORT_START"]),

agents/rap-node-agent/internal/hostagent/windows.go

@@ -70,6 +70,7 @@ func WindowsInstallConfigFromProfile(profile WindowsInstallProfile) WindowsInsta
 			VPNFabricSessionTransportEnabled: profile.VPNFabricSessionTransportEnabled,
 			MeshQUICFabricEnabled:            profile.MeshQUICFabricEnabled,
 			MeshQUICFabricListenAddr:         profile.MeshQUICFabricListenAddr,
+			VPNFabricQUICMaxStreamsPerConn:   profile.VPNFabricQUICMaxStreamsPerConn,
 			MeshListenAddr:                   profile.MeshListenAddr,
 			MeshListenPortMode:               profile.MeshListenPortMode,
 			MeshListenAutoPortStart:          profile.MeshListenAutoPortStart,

docs/architecture/DISTRIBUTED_FABRIC_NODE_PROTOCOL_PLAN.md

@@ -364,6 +364,10 @@ from holding unused peer connections indefinitely.
 QUIC carrier connections now track active logical streams and enforce a
 per-connection stream limit, exposing stream opens/closes and limit rejects in
 transport telemetry.
+The per-connection QUIC stream limit is configurable through
+`RAP_VPN_FABRIC_QUIC_MAX_STREAMS_PER_CONN` /
+`-vpn-fabric-quic-max-streams-per-conn` and propagated by host-agent install
+profiles.
 
 Deliverables: