From 8679c449071f18ba8313f7c3d0eb1ee3eab3d256 Mon Sep 17 00:00:00 2001
From: "J. Eckert" <sargonas@users.noreply.github.com>
Date: Fri, 9 Jan 2026 23:25:07 -0800
Subject: [PATCH 1/2] added error logging to users with no inbound
 accessibility

---
 dht.go             | 47 ++++++++++++++++++++++++++++++++++++++++++++++
 dht_maintenance.go |  1 +
 2 files changed, 48 insertions(+)

diff --git a/dht.go b/dht.go
index 72aa660..37aac50 100644
--- a/dht.go
+++ b/dht.go
@@ -51,6 +51,12 @@ type DHT struct {
 	pendingRequests map[string]chan *DHTMessage
 	pendingMu       sync.RWMutex
 
+	// Inbound connection tracking (for outbound-only detection)
+	startTime           time.Time
+	hasReceivedInbound  bool
+	inboundMu           sync.RWMutex
+	lastInboundWarning  time.Time
+
 	// Shutdown coordination
 	shutdown chan struct{}
 	wg       sync.WaitGroup
@@ -64,6 +70,7 @@ func NewDHT(localSystem *System, storage *Storage, listenAddr string) *DHT {
 		listenAddr:      listenAddr,
 		pendingRequests: make(map[string]chan *DHTMessage),
 		shutdown:        make(chan struct{}),
+		startTime:       time.Now(),
 		httpClient: &http.Client{
 			Timeout: RequestTimeout,
 		},
@@ -106,6 +113,43 @@ func (dht *DHT) Stop() {
 	log.Printf("DHT stopped")
 }
 
+// markInboundReceived records that we've received an inbound connection
+func (dht *DHT) markInboundReceived() {
+	dht.inboundMu.Lock()
+	dht.hasReceivedInbound = true
+	dht.inboundMu.Unlock()
+}
+
+// checkInboundStatus logs a warning if no inbound connections after startup period
+func (dht *DHT) checkInboundStatus() {
+	dht.inboundMu.RLock()
+	hasInbound := dht.hasReceivedInbound
+	lastWarning := dht.lastInboundWarning
+	dht.inboundMu.RUnlock()
+
+	if hasInbound {
+		return
+	}
+
+	// Only warn after 10 minutes of uptime
+	if time.Since(dht.startTime) < 10*time.Minute {
+		return
+	}
+
+	// Repeat warning every 6 hours
+	if !lastWarning.IsZero() && time.Since(lastWarning) < 6*time.Hour {
+		return
+	}
+
+	dht.inboundMu.Lock()
+	dht.lastInboundWarning = time.Now()
+	dht.inboundMu.Unlock()
+
+	log.Printf("WARNING: No inbound connections received after 10 minutes.")
+	log.Printf("  Your node may be in outbound-only mode (can see network but others can't reach you).")
+	log.Printf("  Check that port %s is open and forwarded correctly, as UPnP may have failed.", dht.listenAddr)
+}
+
 // updateRoutingTable adds a node to the peer cache
 // Simplified from Kademlia - we just cache all peers we hear about
 func (dht *DHT) updateRoutingTable(sys *System) {
@@ -218,6 +262,9 @@ func (dht *DHT) handleDHTMessage(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// Mark that we've received an inbound request (not a response)
+	dht.markInboundReceived()
+
 	switch msg.Type {
 	case MessageTypePing:
 		response, err = dht.handlePing(&msg)
diff --git a/dht_maintenance.go b/dht_maintenance.go
index ab57ab9..4051e74 100644
--- a/dht_maintenance.go
+++ b/dht_maintenance.go
@@ -54,6 +54,7 @@ func (dht *DHT) peerLivenessLoop() {
 			return
 		case <-ticker.C:
 			dht.checkPeerLiveness()
+			dht.checkInboundStatus()
 		}
 	}
 }

From 13d9f11df6a63a184ddc250d359f8f320c5823cb Mon Sep 17 00:00:00 2001
From: "J. Eckert" <sargonas@users.noreply.github.com>
Date: Sat, 10 Jan 2026 10:03:23 -0800
Subject: [PATCH 2/2] Fix gossip validation not detecting UUID mismatch on
 success

validateGossipSystems was ignoring the responding system's UUID after
a successful ping. If a different system now lives at an address
(e.g., old node replaced by new one), the stale gossip entry was
incorrectly marked as "verified" instead of being removed.

Now properly checks respSystem.ID != sys.ID and removes stale entries.
---
 dht_maintenance.go | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/dht_maintenance.go b/dht_maintenance.go
index 4051e74..c971a68 100644
--- a/dht_maintenance.go
+++ b/dht_maintenance.go
@@ -209,7 +209,7 @@ func (dht *DHT) validateGossipSystems() {
 		}
 
 		// Try to ping the system directly
-		_, err := dht.Ping(sys.PeerAddress)
+		respSystem, err := dht.Ping(sys.PeerAddress)
 		if err != nil {
 			// Failed to contact - check if this is the expected system
 			// The Ping function already handles UUID mismatches
@@ -224,6 +224,16 @@ func (dht *DHT) validateGossipSystems() {
 				dht.routingTable.RemoveFromCache(sys.ID)
 				removed++
 			}
+		} else if respSystem != nil && respSystem.ID != sys.ID {
+			// UUID mismatch - a different system now lives at this address
+			// The gossip entry is stale, remove it
+			log.Printf("  %s (%s): UUID mismatch - address now belongs to %s (%s), removing stale entry",
+				sys.Name, sys.ID.String()[:8], respSystem.Name, respSystem.ID.String()[:8])
+			dht.routingTable.RemoveFromCache(sys.ID)
+			if err := dht.storage.DeletePeerSystem(sys.ID); err != nil {
+				log.Printf("Warning: failed to delete stale peer system %s: %v", sys.ID.String()[:8], err)
+			}
+			removed++
 		} else {
 			verified++
 			log.Printf("  %s: verified", sys.Name)