diff --git a/tailcfg/tailcfg.go b/tailcfg/tailcfg.go
index 95dc79404..65a9f12d2 100644
--- a/tailcfg/tailcfg.go
+++ b/tailcfg/tailcfg.go
@@ -593,7 +593,7 @@ type NetInfo struct {
 
 	// HavePortMap is whether we have an existing portmap open
 	// (UPnP, PMP, or PCP).
-	HavePortMap bool `json:",omitempty"`
+	HavePortMap opt.Bool
 
 	// UPnP is whether UPnP appears present on the LAN.
 	// Empty means not checked.
@@ -642,11 +642,11 @@ func (ni *NetInfo) String() string {
 }
 
 func (ni *NetInfo) portMapSummary() string {
-	if !ni.HavePortMap && ni.UPnP == "" && ni.PMP == "" && ni.PCP == "" {
+	if ni.HavePortMap == "" && ni.UPnP == "" && ni.PMP == "" && ni.PCP == "" {
 		return "?"
 	}
 	var prefix string
-	if ni.HavePortMap {
+	if v, _ := ni.HavePortMap.Get(); v {
 		prefix = "active-"
 	}
 	return prefix + conciseOptBool(ni.UPnP, "U") + conciseOptBool(ni.PMP, "M") + conciseOptBool(ni.PCP, "C")
diff --git a/tailcfg/tailcfg_clone.go b/tailcfg/tailcfg_clone.go
index b1bef1d68..9bef80dc9 100644
--- a/tailcfg/tailcfg_clone.go
+++ b/tailcfg/tailcfg_clone.go
@@ -177,7 +177,7 @@ var _NetInfoCloneNeedsRegeneration = NetInfo(struct {
 	OSHasIPv6             opt.Bool
 	WorkingUDP            opt.Bool
 	WorkingICMPv4         opt.Bool
-	HavePortMap           bool
+	HavePortMap           opt.Bool
 	UPnP                  opt.Bool
 	PMP                   opt.Bool
 	PCP                   opt.Bool
diff --git a/tailcfg/tailcfg_view.go b/tailcfg/tailcfg_view.go
index dfd48f2bc..f2d77dafe 100644
--- a/tailcfg/tailcfg_view.go
+++ b/tailcfg/tailcfg_view.go
@@ -380,7 +380,7 @@ func (v NetInfoView) WorkingIPv6() opt.Bool           { return v.ж.WorkingIPv6
 func (v NetInfoView) OSHasIPv6() opt.Bool             { return v.ж.OSHasIPv6 }
 func (v NetInfoView) WorkingUDP() opt.Bool            { return v.ж.WorkingUDP }
 func (v NetInfoView) WorkingICMPv4() opt.Bool         { return v.ж.WorkingICMPv4 }
-func (v NetInfoView) HavePortMap() bool               { return v.ж.HavePortMap }
+func (v NetInfoView) HavePortMap() opt.Bool           { return v.ж.HavePortMap }
 func (v NetInfoView) UPnP() opt.Bool                  { return v.ж.UPnP }
 func (v NetInfoView) PMP() opt.Bool                   { return v.ж.PMP }
 func (v NetInfoView) PCP() opt.Bool                   { return v.ж.PCP }
@@ -398,7 +398,7 @@ var _NetInfoViewNeedsRegeneration = NetInfo(struct {
 	OSHasIPv6             opt.Bool
 	WorkingUDP            opt.Bool
 	WorkingICMPv4         opt.Bool
-	HavePortMap           bool
+	HavePortMap           opt.Bool
 	UPnP                  opt.Bool
 	PMP                   opt.Bool
 	PCP                   opt.Bool
diff --git a/wgengine/magicsock/magicsock.go b/wgengine/magicsock/magicsock.go
index 4f2ec7825..46ee89263 100644
--- a/wgengine/magicsock/magicsock.go
+++ b/wgengine/magicsock/magicsock.go
@@ -793,12 +793,12 @@ func (c *Conn) setNetInfoHavePortMap() {
 		// No NetInfo yet. Nothing to update.
 		return
 	}
-	if c.netInfoLast.HavePortMap {
+	if v, _ := c.netInfoLast.HavePortMap.Get(); v {
 		// No change.
 		return
 	}
 	ni := c.netInfoLast.Clone()
-	ni.HavePortMap = true
+	ni.HavePortMap.Set(true)
 	c.callNetInfoCallbackLocked(ni)
 }
 
@@ -834,8 +834,8 @@ func (c *Conn) updateNetInfo(ctx context.Context) (*netcheck.Report, error) {
 		UPnP:                  report.UPnP,
 		PMP:                   report.PMP,
 		PCP:                   report.PCP,
-		HavePortMap:           c.portMapper.HaveMapping(),
 	}
+	ni.HavePortMap.Set(c.portMapper.HaveMapping())
 	for rid, d := range report.RegionV4Latency {
 		ni.DERPLatency[fmt.Sprintf("%d-v4", rid)] = d.Seconds()
 	}