diff --git a/tstest/natlab/vnet/conf.go b/tstest/natlab/vnet/conf.go
index 42629c34e..bb7c258f8 100644
--- a/tstest/natlab/vnet/conf.go
+++ b/tstest/natlab/vnet/conf.go
@@ -65,6 +65,16 @@ func nodeMac(n int) MAC {
 	return MAC{0x52, 0xcc, 0xcc, 0xcc, 0xcc, byte(n)}
 }
 
+var lanSLAACBase = netip.MustParseAddr("fe80::50cc:ccff:fecc:cc01")
+
+// nodeLANIP6 returns a node number's Link Local SLAAC IPv6 address,
+// such as fe80::50cc:ccff:fecc:cc03 for node 3.
+func nodeLANIP6(n int) netip.Addr {
+	a := lanSLAACBase.As16()
+	a[15] = byte(n)
+	return netip.AddrFrom16(a)
+}
+
 // AddNode creates a new node in the world.
 //
 // The opts may be of the following types:
@@ -128,6 +138,7 @@ type TailscaledEnv struct {
 // The opts may be of the following types:
 //   - string IP address, for the network's WAN IP (if any)
 //   - string netip.Prefix, for the network's LAN IP (defaults to 192.168.0.0/24)
+//     if IPv4, or its WAN IPv6 + CIDR (e.g. "2000:52::1/64")
 //   - NAT, the type of NAT to use
 //   - NetworkService, a service to add to the network
 //
diff --git a/tstest/natlab/vnet/vnet.go b/tstest/natlab/vnet/vnet.go
index dbf855cc0..d88040ab7 100644
--- a/tstest/natlab/vnet/vnet.go
+++ b/tstest/natlab/vnet/vnet.go
@@ -820,7 +820,20 @@ func (c vmClient) proto() Protocol {
 	return ProtocolUnixDGRAM
 }
 
-const ethernetHeaderLen = 14
+func parseEthernet(pkt []byte) (dst, src MAC, ethType layers.EthernetType, payload []byte, ok bool) {
+	// headerLen is the length of an Ethernet header:
+	// 6 bytes of destination MAC, 6 bytes of source MAC, 2 bytes of EtherType.
+	const headerLen = 14
+	if len(pkt) < headerLen {
+		return
+	}
+	dst = MAC(pkt[0:6])
+	src = MAC(pkt[6:12])
+	ethType = layers.EthernetType(binary.BigEndian.Uint16(pkt[12:14]))
+	payload = pkt[headerLen:]
+	ok = true
+	return
+}
 
 // Handles a single connection from a QEMU-style client or muxd connections for dgram mode
 func (s *Server) ServeUnixConn(uc *net.UnixConn, proto Protocol) {
@@ -878,10 +891,10 @@ func (s *Server) ServeUnixConn(uc *net.UnixConn, proto Protocol) {
 		c := vmClient{uc, raddr}
 
 		// For the first packet from a MAC, register a writerFunc to write to the VM.
-		if len(packetRaw) < ethernetHeaderLen {
+		_, srcMAC, _, _, ok := parseEthernet(packetRaw)
+		if !ok {
 			continue
 		}
-		srcMAC := MAC(packetRaw[6:12])
 		srcNode, ok := s.nodeByMAC[srcMAC]
 		if !ok {
 			s.logf("[conn %p] got frame from unknown MAC %v", c.uc, srcMAC)
@@ -961,12 +974,12 @@ func (s *Server) routeUDPPacket(up UDPPacket) {
 //
 // It reports whether a packet was written to any clients.
 func (n *network) writeEth(res []byte) bool {
-	if len(res) < 12 {
+	dstMAC, srcMAC, etherType, _, ok := parseEthernet(res)
+	if !ok {
 		return false
 	}
-	dstMAC := MAC(res[0:6])
-	srcMAC := MAC(res[6:12])
-	if dstMAC.IsBroadcast() {
+
+	if dstMAC.IsBroadcast() || (n.v6 && etherType == layers.EthernetTypeIPv6 && dstMAC == macAllNodes) {
 		num := 0
 		n.writers.Range(func(mac MAC, nw networkWriter) bool {
 			if mac != srcMAC {
@@ -996,6 +1009,7 @@ func (n *network) writeEth(res []byte) bool {
 }
 
 var (
+	macAllNodes   = MAC{0: 0x33, 1: 0x33, 5: 0x01}
 	macAllRouters = MAC{0: 0x33, 1: 0x33, 5: 0x02}
 	macBroadcast  = MAC{0xff, 0xff, 0xff, 0xff, 0xff, 0xff}
 )
@@ -1007,7 +1021,7 @@ const (
 func (n *network) HandleEthernetPacket(ep EthernetPacket) {
 	packet := ep.gp
 	dstMAC := ep.DstMAC()
-	isBroadcast := dstMAC.IsBroadcast()
+	isBroadcast := dstMAC.IsBroadcast() || (n.v6 && ep.le.EthernetType == layers.EthernetTypeIPv6 && dstMAC == macAllNodes)
 	isV6SpecialMAC := dstMAC[0] == 0x33 && dstMAC[1] == 0x33
 
 	// forRouter is whether the packet is destined for the router itself
@@ -1016,7 +1030,7 @@ func (n *network) HandleEthernetPacket(ep EthernetPacket) {
 
 	const debug = false
 	if debug {
-		n.logf("HandleEthernetPacket: %v => %v; type %v, forRouter=%v", ep.SrcMAC(), ep.DstMAC(), ep.le.EthernetType, forRouter)
+		n.logf("HandleEthernetPacket: %v => %v; type %v, bcast=%v, forRouter=%v", ep.SrcMAC(), ep.DstMAC(), ep.le.EthernetType, isBroadcast, forRouter)
 	}
 
 	switch ep.le.EthernetType {
@@ -1058,7 +1072,7 @@ func (n *network) HandleEthernetPacket(ep EthernetPacket) {
 				// log spam when verbose logging is enabled.
 				return
 			}
-			if isMcast {
+			if isMcast && !isBroadcast {
 				return
 			}
 		}
diff --git a/tstest/natlab/vnet/vnet_test.go b/tstest/natlab/vnet/vnet_test.go
index e816dbdba..4995a603b 100644
--- a/tstest/natlab/vnet/vnet_test.go
+++ b/tstest/natlab/vnet/vnet_test.go
@@ -69,13 +69,15 @@ func TestPacketSideEffects(t *testing.T) {
 			netName: "v6",
 			setup: func() (*Server, error) {
 				var c Config
-				c.AddNode(c.AddNetwork("2000:52::1/64"))
+				nw := c.AddNetwork("2000:52::1/64")
+				c.AddNode(nw)
+				c.AddNode(nw)
 				return New(&c)
 			},
 			tests: []netTest{
 				{
 					name: "router-solicit",
-					pkt:  mkIPv6RouterSolicit(nodeMac(1), netip.MustParseAddr("fe80::50cc:ccff:fecc:cc01")),
+					pkt:  mkIPv6RouterSolicit(nodeMac(1), nodeLANIP6(1)),
 					check: all(
 						logSubstr("sending IPv6 router advertisement to 52:cc:cc:cc:cc:01 from 52:ee:ee:ee:ee:01"),
 						numPkts(1),
@@ -84,6 +86,16 @@ func TestPacketSideEffects(t *testing.T) {
 						pktSubstr("SrcMAC=52:ee:ee:ee:ee:01 DstMAC=52:cc:cc:cc:cc:01 EthernetType=IPv6"),
 					),
 				},
+				{
+					name: "all-nodes",
+					pkt:  mkAllNodesPing(nodeMac(1), nodeLANIP6(1)),
+					check: all(
+						numPkts(1),
+						pktSubstr("SrcMAC=52:cc:cc:cc:cc:01 DstMAC=33:33:00:00:00:01"),
+						pktSubstr("SrcIP=fe80::50cc:ccff:fecc:cc01 DstIP=ff02::1"),
+						pktSubstr("TypeCode=EchoRequest"),
+					),
+				},
 			},
 		},
 	}
@@ -105,7 +117,9 @@ func TestPacketSideEffects(t *testing.T) {
 						})
 					}
 
-					s.handleEthernetFrameFromVM(tt.pkt)
+					if err := s.handleEthernetFrameFromVM(tt.pkt); err != nil {
+						t.Fatal(err)
+					}
 					if tt.check != nil {
 						if err := tt.check(se); err != nil {
 							t.Fatal(err)
@@ -156,13 +170,31 @@ func mkIPv6RouterSolicit(srcMAC MAC, srcIP netip.Addr) []byte {
 		}},
 	}
 	icmp.SetNetworkLayerForChecksum(ip)
+	return mkEth(macAllRouters, srcMAC, layers.EthernetTypeIPv6, mkPacket(ip, icmp, ra))
+}
+
+func mkPacket(layers ...gopacket.SerializableLayer) []byte {
 	buf := gopacket.NewSerializeBuffer()
-	options := gopacket.SerializeOptions{FixLengths: true, ComputeChecksums: true}
-	if err := gopacket.SerializeLayers(buf, options, ip, icmp, ra); err != nil {
-		panic(fmt.Sprintf("serializing ICMPv6 RA: %v", err))
+	opts := gopacket.SerializeOptions{FixLengths: true, ComputeChecksums: true}
+	if err := gopacket.SerializeLayers(buf, opts, layers...); err != nil {
+		panic(fmt.Sprintf("serializing packet: %v", err))
 	}
+	return buf.Bytes()
+}
 
-	return mkEth(macAllRouters, srcMAC, layers.EthernetTypeIPv6, buf.Bytes())
+func mkAllNodesPing(srcMAC MAC, srcIP netip.Addr) []byte {
+	ip := &layers.IPv6{
+		Version:    6,
+		HopLimit:   255,
+		NextHeader: layers.IPProtocolICMPv6,
+		SrcIP:      srcIP.AsSlice(),
+		DstIP:      net.ParseIP("ff02::1"), // all nodes
+	}
+	icmp := &layers.ICMPv6{
+		TypeCode: layers.CreateICMPv6TypeCode(layers.ICMPv6TypeEchoRequest, 0),
+	}
+	icmp.SetNetworkLayerForChecksum(ip)
+	return mkEth(macAllNodes, srcMAC, layers.EthernetTypeIPv6, mkPacket(ip, icmp))
 }
 
 // sideEffects gathers side effects as a result of sending a packet and tests
@@ -198,7 +230,7 @@ func logSubstr(sub string) func(*sideEffects) error {
 				return nil
 			}
 		}
-		return fmt.Errorf("expected log substring %q not found; log statements were %q", sub, se.logs)
+		return fmt.Errorf("expected log substring %q not found; log statements were:\n%s", sub, strings.Join(se.logs, "\n"))
 	}
 }