Fixes that an interface has both a local link and dhcp address - confuses dante.

src/service/10-link-local-mgmt

@@ -0,0 +1,83 @@
+#!/bin/bash
+# NetworkManager dispatcher script: 10-link-local-mgmt
+#
+# Temporarily suppresses IPv4 link-local when a DHCP address is available,
+# using nmcli device modify (active session only, NOT saved to the profile).
+# The persistent profile always keeps ipv4.link-local=enabled so that
+# direct-connect (no DHCP) plug-ins always activate and trigger events.
+#
+# Triggers: up, down, dhcp4-change on ethernet interfaces
+# Install to: /etc/NetworkManager/dispatcher.d/10-link-local-mgmt
+# Permissions: root:root 0755
+
+INTERFACE="$1"
+ACTION="$2"
+CONNECTION_NAME="${CONNECTION_ID:-}"
+
+# Only handle ethernet interfaces
+if [[ ! "$INTERFACE" =~ ^eth ]]; then
+    exit 0
+fi
+
+# If CONNECTION_ID env var is not set, look up the active connection for this interface
+if [ -z "$CONNECTION_NAME" ]; then
+    CONNECTION_NAME=$(nmcli -t -f NAME,DEVICE connection show --active 2>/dev/null \
+        | grep ":${INTERFACE}$" | cut -d: -f1 | head -n1)
+    [ -z "$CONNECTION_NAME" ] && exit 0
+fi
+
+# Update /etc/avahi/hosts to point mDNS hostname at the best available DHCP address
+# across all ethernet interfaces (so Avahi doesn't advertise a link-local address).
+update_avahi() {
+    local hostname
+    hostname=$(hostname)
+    # Find first non-link-local IPv4 across all ethernet interfaces
+    local dhcp_ip
+    dhcp_ip=$(ip -4 addr show 2>/dev/null \
+        | grep -A5 ': eth' \
+        | grep -oP '(?<=inet\s)\d+(\.\d+){3}' \
+        | grep -v '^127\.' \
+        | grep -v '^169\.254\.' \
+        | head -n1)
+
+    if [ -n "$dhcp_ip" ]; then
+        mkdir -p /etc/avahi
+        echo "$dhcp_ip $hostname $hostname.local" > /etc/avahi/hosts
+        logger -t nm-link-local "Avahi: pinned $hostname -> $dhcp_ip"
+    else
+        rm -f /etc/avahi/hosts
+        logger -t nm-link-local "Avahi: removed hosts pin, using all addresses"
+    fi
+    systemctl restart avahi-daemon 2>/dev/null
+}
+
+case "$ACTION" in
+    up|dhcp4-change)
+        DHCP_IP=$(ip -4 addr show "$INTERFACE" 2>/dev/null \
+            | grep -oP '(?<=inet\s)\d+(\.\d+){3}' \
+            | grep -v '^127\.' \
+            | grep -v '^169\.254\.' \
+            | head -n1)
+
+        if [ -n "$DHCP_IP" ]; then
+            logger -t nm-link-local "[$INTERFACE] DHCP $DHCP_IP detected — suppressing link-local (session only)"
+            # Use device modify (not connection modify) so the persistent profile keeps
+            # ipv4.link-local=enabled. This ensures direct-connect plug-ins always activate.
+            # Run in background after a delay — nmcli blocks on NM, which is waiting for
+            # this dispatcher to return, causing a deadlock if called synchronously.
+            (sleep 2 && nmcli device modify "$INTERFACE" ipv4.link-local disabled 2>/dev/null \
+                && logger -t nm-link-local "[$INTERFACE] Link-local suppressed for current session") &
+        else
+            logger -t nm-link-local "[$INTERFACE] No DHCP on $INTERFACE — keeping link-local active"
+        fi
+        update_avahi
+        ;;
+
+    down)
+        # Profile always has ipv4.link-local=enabled so no action needed here.
+        # The suppression from device modify was session-only and is gone when the
+        # connection goes down.
+        logger -t nm-link-local "[$INTERFACE] Down — link-local will be active on next connect"
+        update_avahi
+        ;;
+esac

src/service/update_and_run_server_and_frontend.sh

@@ -14,24 +14,10 @@ while IFS=: read -r name type; do
     fi
 done < <(nmcli -t -f NAME,TYPE connection show)
 
-# Configure Avahi to prefer DHCP address over static fallback for mDNS
-# Get the DHCP-assigned IP (first non-localhost, non-192.168.42.10 IP)
-DHCP_IP=$(ip -4 addr show eth0 2>/dev/null | grep -oP '(?<=inet\s)\d+(\.\d+){3}' | grep -v '^127\.' | grep -v '^169\.254\.' | head -n1)
-HOSTNAME=$(hostname)
-
-if [ -n "$DHCP_IP" ]; then
-    echo "DHCP address detected: $DHCP_IP, configuring Avahi to prefer it for mDNS."
-    # Add entry to /etc/avahi/hosts to explicitly map hostname to DHCP IP
-    sudo mkdir -p /etc/avahi
-    echo "$DHCP_IP $HOSTNAME $HOSTNAME.local" | sudo tee /etc/avahi/hosts > /dev/null
-    # Restart avahi to apply the hosts file
-    sudo systemctl restart avahi-daemon
-else
-    echo "No DHCP address detected, mDNS will use link local"
-    # Remove hosts file to let Avahi advertise all IPs
-    sudo rm -f /etc/avahi/hosts
-    sudo systemctl restart avahi-daemon
-fi
+# Install NetworkManager dispatcher script for link-local / Avahi management
+sudo cp /home/caster/bumble-auracast/src/service/10-link-local-mgmt /etc/NetworkManager/dispatcher.d/10-link-local-mgmt
+sudo chown root:root /etc/NetworkManager/dispatcher.d/10-link-local-mgmt
+sudo chmod 755 /etc/NetworkManager/dispatcher.d/10-link-local-mgmt
 
 # Copy system service file for frontend
 sudo cp /home/caster/bumble-auracast/src/service/auracast-frontend.service /etc/systemd/system/auracast-frontend.service