Running Sonos Across Ubiquiti UniFi VLANs: A Technical Deep Dive

November 19, 2025 Roberto Di Sisto Networking , , , , , , ,

A Proof of Concept for Network Segmentation Enthusiasts

Introduction: Why This Guide Exists (And Why You Probably Don’t Need It)

An important disclaimer: You probably don’t need this guide.

If you’re reading this, you might be considering isolating your Sonos speakers on a separate VLAN from your control devices (phones, tablets, computers). Before you spend hours configuring firewall rules, consider this: Sonos doesn’t collect or transmit sensitive personal data that would justify this level of network isolation. Unlike many IoT devices with questionable privacy practices, Sonos speakers primarily communicate with music streaming services and receive commands from your controllers. They’re not data harvesting devices.

The simple solution? Keep your Sonos and controllers on the same network. It just works. No firewall rules, no mDNS complications, no troubleshooting. Done.

So why does this guide exist?

This article serves as a proof of concept demonstrating that it is technically possible to run Sonos speakers on one VLAN while controlling them from another. Maybe you’re:

  • A network engineer curious about the technical requirements
  • Building a complex home lab and want to understand cross-VLAN multicast
  • Required by company policy to segment IoT devices
  • Simply enjoy the challenge of making things work the hard way

This guide documents the exact firewall rules, mDNS configuration, and IGMP settings required to make Sonos work across VLANs on a UniFi Dream Machine Pro running Network 9.5.21. It represents hours of testing, packet captures, and log analysis, so you don’t have to repeat that work.

Fair warning: This is advanced networking. Expect to spend 2-3 hours on configuration and troubleshooting. If you just want to listen to music, put everything on the same VLAN and save yourself the headache.

Still here? Let’s dive in.

Network Topology & Requirements

Test Environment

For this proof of concept, the setup uses:

  • UniFi Dream Machine Pro – Firmware 4.4.6
  • UniFi Network Application version 9.5.21
  • UniFi Access Points – Firmware 8.2.17.17828
  • UniFi Switches – Firmware 7.2.123.16565 and 2.1.8.971
  • Two VLANs:
    • Private VLAN 192 (10.0.192.0/24) – Controllers (MacBooks, iPhones, iPads)
    • IoT VLAN 40 (10.0.40.0/24) – Sonos speakers

Sonos System Versions (at time of testing):

  • Sonos Controller for iOS: 80.32.36
  • Hardware: 17.6 (build 92.0-70280)
  • iOS: 26.1
  • Spotify: 9.0.96.828

Note: Sonos S1 was not tested. This configuration was tested exclusively with Sonos S2.

VLAN IDs and subnet addresses are arbitrary examples. You can use any VLAN IDs and IP ranges that fit your network design.

Physical Network Setup

Critical Setup Details:

All Sonos devices in this configuration were connected via Ethernet cable, including:

  • Primary speakers
  • Home Theater satellites (Sub and Rear speakers)

WiFi Configuration:

  • WiFi modules were disabled on all wired Sonos devices to prevent Spanning Tree Protocol (STP) conflicts
  • STP was completely disabled in the UniFi system
  • Wireless Sonos speakers were assigned to a dedicated “IoT” WiFi network mapped to the VLAN 40 IoT
  • Controllers (iPhones, iPads, MacBooks) connect to the Private VLAN 192 WiFi network

Initial Setup Process:

  • All Sonos devices were pre-configured and set up before being transferred to the IoT network
  • Whether new devices can be added after the VLAN separation was not tested
  • It is recommended to fully configure your Sonos system on a single VLAN first, then migrate to the segregated setup

Goal

Goal: Control Sonos speakers in VLAN 40 from devices in VLAN 192, with full functionality:

  • ✅ Sonos App control (iOS, Android, Desktop)
  • ✅ AirPlay 2 streaming
  • ✅ Multi-room audio and grouping
  • ✅ Spotify Connect (optional)
  • ✅ Music streaming from internet services

Why This Is Complicated

Sonos relies heavily on:

  1. Multicast DNS (mDNS) – For device discovery (port 5353/UDP)
  2. SSDP (Simple Service Discovery Protocol) – For UPnP discovery (port 1900/UDP)
  3. IGMP (Internet Group Management Protocol) – For multicast group management
  4. Bidirectional communication – Controllers send commands, but speakers also initiate callbacks

All of these protocols are designed for single-subnet operation. Making them work across VLANs requires:

  • mDNS repeating/reflection
  • IGMP proxy configuration
  • Precise firewall rules allowing specific bidirectional traffic
  • Multicast address routing between VLANs

Prerequisites

Before you begin, ensure you have:

Hardware & Software

  • UniFi Dream Machine Pro (or UDM, UDM-SE)
  • UniFi Network Application 9.5.21 or newer
  • Static DHCP reservations for all Sonos devices

Network Configuration

  • Two or more VLANs already configured
  • Basic understanding of Zone-Based Firewall in UniFi Network 9.x
  • All Sonos speakers connected and working (test on same VLAN first!)

Time Investment

  • Configuration: 1-2 hours
  • Testing & troubleshooting: 1-2 hours
  • Total: 2-4 hours depending on experience

Part 1: IP Groups and Port Groups

Before creating firewall rules, define reusable groups for cleaner configuration.

Navigate to Groups

Settings → Overview → scroll down to “Network Lists”

Create IP Group: Sonos_Devices

Purpose: Contains all Sonos speaker IP addresses for targeted firewall rules

Type: Address Group
Name: Sonos_Devices
Addresses: 
  - 10.0.40.10  (Sonos Living Room)
  - 10.0.40.11  (Sonos Kitchen)
  - 10.0.40.12  (Sonos Bedroom)
  - 10.0.40.13  (Sonos Bathroom)
  ... (add all your Sonos devices)

Critical: Use static DHCP reservations! Dynamic IPs will break your firewall rules.

Create Port Group: Sonos_Control

Purpose: TCP ports for Sonos app control and callbacks

Type: Port Group
Name: Sonos_Control
Ports: 1400, 1443, 3400, 3401, 3500, 4444

Port breakdown:

  • 1400 – Primary HTTP control API
  • 1443 – HTTPS secure control API
  • 3400 – Desktop controller callbacks (Mac/Windows)
  • 3401 – iOS app callbacks
  • 3500 – Android app callbacks
  • 4444 – Firmware updates and advanced features

Create Port Group: Sonos_Discovery

Purpose: UDP ports for device discovery and SSDP

Type: Port Group
Name: Sonos_Discovery
Ports: 1900, 1901, 5353, 6969

Port breakdown:

  • 1900 – SSDP discovery requests
  • 1901 – SSDP discovery responses
  • 5353 – mDNS (Multicast DNS)
  • 6969 – Initial speaker configuration

Create Port Group: AirPlay_TCP

Purpose: TCP ports for AirPlay 2 streaming

Type: Port Group
Name: AirPlay_TCP
Ports: 5000, 5001, 7000, 7001, 7100

Port breakdown:

  • 5000, 5001 – AirPlay audio streaming
  • 7000, 7001, 7100 – AirPlay video/screen mirroring

Create Port Group: AirPlay_UDP

Purpose: UDP ports for AirPlay 2 and PTP time synchronization

Type: Port Group
Name: AirPlay_UDP
Ports: 319, 320, 6002, 6010

Port breakdown:

  • 319, 320 – PTP (Precision Time Protocol) for multi-room sync
  • 6002 – AirPlay audio data
  • 6010 – AirPlay alternative audio channel

Part 2: Zone-Based Firewall Rules

UniFi Network 9.x uses Zone-Based Firewalling. Unlike traditional firewalls, rule order is handled automatically. Custom rules take precedence over built-in rules.

⚠️ CRITICAL WARNING: The firewall rules listed below are the ONLY custom rules that existed in the test environment. If you have other custom firewall rules in your configuration, there is a risk of rule conflicts and overlapping behavior that could interfere with Sonos functionality. It is recommended to test this configuration in an environment with minimal or no other custom rules.

Navigate to Firewall

Settings → Policy Engine: Policy Table → Create New Policy

Note: Rules are numbered (01, 02, 03, etc.) for easier reference and organization in the UniFi interface. After creating rules, allow a few minutes for them to become active.

Rule 1: Allow Established/Related Traffic

Purpose: Allows return traffic for established connections

Name: 01 Allow Established Related
Source Zone: Internal
Source: Any
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: Any
Destination Port: Any

IP Version: Both
Protocol: All
Connection State: ☑ Return Traffic (ONLY this checkbox!)

Description: Allows return traffic for established connections

Why this matters: This rule ensures that response packets for connections initiated by other rules are automatically allowed. It should match the built-in “Allow Return Traffic” policy but gives you explicit control.

Rule 2: IGMP Multicast (Private → IoT)

Purpose: Allows IGMP protocol for multicast group management

Name: 02 IGMP Private to IoT
Source Zone: Internal
Source: Network → Private (VLAN 192)
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: Network → IoT (VLAN 40)
Destination Port: Any

IP Version: IPv4 ⚠️ (IGMP only available on IPv4!)
Protocol: Custom → IGMP
Connection State: All

Description: IGMP multicast for Sonos discovery Private to IoT

Technical note: IGMP is an IPv4-specific protocol (protocol number 2). You cannot select “Both” for IP Version—IPv4 is the only option. This is correct and expected behavior.

Rule 3: IGMP Multicast (IoT → Private)

Purpose: IGMP return path from speakers to controllers

Name: 03 IGMP IoT to Private
Source Zone: Internal
Source: Network → IoT (VLAN 40)
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: Network → Private (VLAN 192)
Destination Port: Any

IP Version: IPv4
Protocol: Custom → IGMP
Connection State: All

Description: IGMP multicast return path IoT to Private

Rule 4: mDNS Multicast (Private → Multicast Address)

Purpose: Allows mDNS discovery packets to multicast address

Name: 04 mDNS Private to Multicast
Source Zone: Internal
Source: Network → Private (VLAN 192)
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: IP → 224.0.0.251
Destination Port: Specific → 5353

IP Version: Both
Protocol: UDP
Connection State: All

Description: mDNS discovery from Private to multicast address

Technical note: 224.0.0.251 is the reserved mDNS multicast address. All mDNS queries are sent to this address.

Rule 5: mDNS Multicast (IoT → Multicast Address)

Purpose: Allows Sonos speakers to send mDNS responses

Name: 05 mDNS IoT to Multicast
Source Zone: Internal
Source: Network → IoT (VLAN 40)
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: IP → 224.0.0.251
Destination Port: Specific → 5353

IP Version: Both
Protocol: UDP
Connection State: All

Description: mDNS discovery from IoT to multicast address

Rule 6: SSDP Multicast (Private → Multicast Address)

Purpose: Allows SSDP/UPnP discovery from controllers

Name: 06 SSDP Private to Multicast
Source Zone: Internal
Source: Network → Private (VLAN 192)
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: IP → 239.255.255.250
Destination Port: Specific → 1900

IP Version: Both
Protocol: UDP
Connection State: All

Description: SSDP discovery from Private to multicast address

Technical note: 239.255.255.250 is the SSDP multicast address used by UPnP devices.

Rule 7: SSDP Multicast (IoT → Multicast Address)

Purpose: Allows Sonos speakers to respond to SSDP discovery

Name: 07 SSDP IoT to Multicast
Source Zone: Internal
Source: Network → IoT (VLAN 40)
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: IP → 239.255.255.250
Destination Port: Specific → 1900

IP Version: Both
Protocol: UDP
Connection State: All

Description: SSDP discovery from IoT to multicast address

Rule 8: Sonos Control Ports (Private → Sonos TCP)

Purpose: Allows controller apps to send commands to speakers

Name: 08 Sonos Control Private to IoT
Source Zone: Internal
Source: Network → Private (VLAN 192)
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: IP → IP Group "Sonos_Devices"
Destination Port: List → Port Group "Sonos_Control"

IP Version: Both
Protocol: TCP
Connection State: All

Description: Sonos App control ports 1400, 1443, 3400-3401, 3500, 4444

Rule 9: Sonos Callbacks Port 3400 (IoT → Private) ⚠️ CRITICAL

Purpose: Allows speakers to send event notifications to desktop controllers

Name: 09 Sonos Callbacks IoT to Private #3400
Source Zone: Internal
Source: IP → IP Group "Sonos_Devices"
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: Network → Private (VLAN 192)
Destination Port: Specific → 3400

IP Version: Both
Protocol: TCP
Connection State: All (NOT just Return Traffic!)

Description: Sonos event callbacks to Desktop/Mac controllers - Port 3400

Critical: Connection State must be “All”, not just “Return Traffic”! Sonos speakers initiate these connections.

Rule 10: Sonos Callbacks Port 3401 (IoT → Private) ⚠️ CRITICAL

Purpose: Allows speakers to send event notifications to iOS controllers

Name: 10 Sonos Callbacks IoT to Private #3401
Source Zone: Internal
Source: IP → IP Group "Sonos_Devices"
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: Network → Private (VLAN 192)
Destination Port: Specific → 3401

IP Version: Both
Protocol: TCP
Connection State: All

Description: Sonos event callbacks to iOS controllers - Port 3401

Rule 11: Sonos Callbacks Port 3500 (IoT → Private) ⚠️ CRITICAL

Purpose: Allows speakers to send event notifications to Android controllers

Name: 11 Sonos Callbacks IoT to Private #3500
Source Zone: Internal
Source: IP → IP Group "Sonos_Devices"
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: Network → Private (VLAN 192)
Destination Port: Specific → 3500

IP Version: Both
Protocol: TCP
Connection State: All

Description: Sonos event callbacks to Android controllers - Port 3500

Why three separate rules? Port groups in the destination field don’t reliably work for callback scenarios. Separate rules ensure each platform’s callbacks function correctly.

Rule 12: Sonos Discovery UDP (IoT → Private)

Purpose: Allows SSDP and mDNS responses from speakers to controllers

Name: 12 Sonos Discovery Replies IoT to Private
Source Zone: Internal
Source: IP → IP Group "Sonos_Devices"
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: Network → Private (VLAN 192)
Destination Port: List → Port Group "Sonos_Discovery"

IP Version: Both
Protocol: UDP
Connection State: All

Description: Sonos discovery UDP responses ports 1900, 1901, 5353, 6969

Rule 13: AirPlay Control TCP (Private → Sonos)

Purpose: Allows AirPlay 2 streaming from Apple devices to Sonos

Name: 13 AirPlay TCP Private to IoT
Source Zone: Internal
Source: Network → Private (VLAN 192)
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: IP → IP Group "Sonos_Devices"
Destination Port: List → Port Group "AirPlay_TCP"

IP Version: Both
Protocol: TCP
Connection State: All

Description: AirPlay TCP streaming ports 5000, 5001, 7000, 7001, 7100

Rule 14: AirPlay Audio & PTP UDP (Private → Sonos)

Purpose: Allows AirPlay audio data and time synchronization

Name: 14 AirPlay UDP Private to IoT
Source Zone: Internal
Source: Network → Private (VLAN 192)
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: IP → IP Group "Sonos_Devices"
Destination Port: List → Port Group "AirPlay_UDP"

IP Version: Both
Protocol: UDP
Connection State: All

Description: AirPlay UDP audio & PTP ports 319, 320, 6002, 6010

Rule 15: AirPlay PTP Sync (IoT → Private)

Purpose: Allows PTP time synchronization responses for multi-room audio

Name: 15 AirPlay PTP IoT to Private
Source Zone: Internal
Source: IP → IP Group "Sonos_Devices"
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: Network → Private (VLAN 192)
Destination Port: List → Port Group "AirPlay_UDP"

IP Version: Both
Protocol: UDP
Connection State: All

Description: AirPlay PTP return path for multi-room sync

Rule 16: High Ephemeral Ports UDP (IoT → Private)

Purpose: Allows streaming data over high UDP ports

Name: 16 High Ports UDP IoT to Private
Source Zone: Internal
Source: IP → IP Group "Sonos_Devices"
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: Network → Private (VLAN 192)
Destination Port: Specific → 30000-65535 (range)

IP Version: Both
Protocol: UDP
Connection State: All

Description: High ephemeral ports for streaming data UDP

Technical note: Sonos uses dynamic high ports for audio streaming. This range allows that traffic.

Rule 17: High Ephemeral Ports TCP (IoT → Private)

Purpose: Allows AirPlay dynamic connections over high TCP ports

Name: 17 High Ports TCP IoT to Private
Source Zone: Internal
Source: IP → IP Group "Sonos_Devices"
Source Port: Any

Action: Allow
Auto Allow Return Traffic: ☑ (enabled)

Destination Zone: Internal
Destination: Network → Private (VLAN 192)
Destination Port: Specific → 49152-65535 (range)

IP Version: Both
Protocol: TCP
Connection State: All

Description: AirPlay ephemeral TCP ports for dynamic connections

Rule 18: Spotify Connect Direct Control (Optional)

Purpose: Allows Spotify to send control commands from the internet to your Sonos speakers

Name: 18 Spotify Connect to Sonos
Source Zone: External
Source: Any
Source Port: Any

Action: Allow
⚠️ Auto Allow Return Traffic: NOT AVAILABLE (Source = External)

Destination Zone: Internal
Destination: IP → IP Group "Sonos_Devices"
Destination Port: Specific → 4070

IP Version: Both
Protocol: TCP
Connection State: All

Description: Spotify Connect incoming events for Direct Control

Security Warning: This rule allows incoming connections from the internet to your Sonos speakers on port 4070. This is required for Spotify Connect “Direct Control” (controlling Sonos directly from the Spotify app).

Rule 19: Block All Other IoT to LAN (Optional)

Purpose: Deny all other traffic from IoT to Private VLAN (default deny)

Name: 19 Block IoT to Private
Source Zone: Internal
Source: Network → IoT (VLAN 40)
Source Port: Any

Action: Drop
Auto Allow Return Traffic: ☐ (disabled)

Destination Zone: Internal
Destination: Network → Private (VLAN 192)
Destination Port: Any

IP Version: Both
Protocol: All
Connection State: All

Description: Blocks all other traffic from IoT to Private VLAN

Purpose: Explicit deny rule for visibility and security audit purposes. UniFi’s implicit deny would block this anyway, but having an explicit rule helps with troubleshooting and logging.

Part 3: mDNS Configuration

UniFi Network 9.x includes native mDNS reflection, which eliminates the need for external multicast-relay scripts.

Enable mDNS on Private VLAN

Settings → Networks → Private (VLAN 192) → Advanced

Manual:

  • ☑ Multicast DNS (mDNS): ENABLED

Enable mDNS on IoT VLAN

Settings → Networks → IoT (VLAN 40) → Advanced

Manual:

  • ☑ Multicast DNS (mDNS): ENABLED

That’s it. No additional scripts needed. UniFi automatically bridges mDNS queries between VLANs with mDNS enabled.

Part 4: IGMP Configuration

IGMP (Internet Group Management Protocol) is critical for multicast traffic like Sonos multi-room audio.

Enable IGMP Snooping on Private VLAN

Settings → Networks → Private (VLAN 192) → Advanced

Manual:

  • ☑ IGMP Snooping: ENABLED

Enable IGMP Snooping on IoT VLAN

Settings → Networks → IoT (VLAN 40) → Advanced

Manual:

  • ☑ IGMP Snooping: ENABLED

WiFi Network Settings (if using wireless Sonos)

If your Sonos speakers are wireless (not recommended for cross-VLAN), ensure multicast enhancement is disabled:

Settings → Wireless Networks → [IoT SSID] → Advanced

Manual:

  • ☐ Multicast and Broadcast Control: DISABLED
  • ☐ Block LAN to WLAN Multicast and Broadcast Data: DISABLED

Warning: “Multicast and Broadcast Control” will completely block Sonos discovery if enabled!

Part 5: Testing & Troubleshooting

Verification Checklist

Before troubleshooting, verify:

✅ Static IPs:

  • All Sonos devices have static DHCP reservations
  • IP addresses match your firewall rules

✅ mDNS Enabled:

  • Both Private and IoT VLANs have mDNS enabled
  • Check: Settings → Networks → [VLAN] → Advanced → mDNS

✅ IGMP Snooping Enabled:

  • Both VLANs have IGMP snooping enabled
  • Check: Settings → Networks → [VLAN] → Advanced → IGMP Snooping

✅ Firewall Rules Active:

  • Wait 2-3 minutes after creating rules for them to take effect
  • Check: Settings → Policy Engine: Policy Table

✅ IP Groups Correct:

  • Sonos_Devices group contains all speaker IPs
  • Check: Settings → Overview → Network Lists

Testing Procedure

1. Test from Sonos App (iOS/Android/Desktop):

Open Sonos app → Should auto-discover all speakers
Try: Play music, adjust volume, group speakers
Expected: All functions work normally

2. Test AirPlay 2:

iOS/macOS Control Center → AirPlay icon → Select Sonos speaker
Try: Stream music, group multiple speakers
Expected: Audio streams with no dropouts

3. Test Spotify Connect (if Rule 18 enabled):

Spotify app → Play music → Devices Available → Select Sonos
Expected: Sonos appears as available device

4. Test Multi-Room Audio:

Sonos app → Group multiple speakers
Play music → Adjust group volume
Expected: Perfect synchronization across rooms

Common Issues & Solutions

Issue 1: Sonos App Can’t Find Speakers

Diagnosis: mDNS/SSDP discovery not working.

Solution:

  • Verify mDNS enabled on both VLANs (Part 3)
  • Check Rules 4, 5, 6 & 7 (mDNS and SSDP Discovery)
  • Restart Sonos app
  • Reboot speakers: Unplug for 10 seconds
  • Check UniFi logs for blocked packets

Advanced troubleshooting:

1. SSH to UDM Pro
ssh admin@

1. Check for mDNS traffic
tcpdump -i br192 port 5353
tcpdump -i br40 port 5353

Issue 2: App Finds Speakers But Can’t Control Them

Diagnosis: mDNS/SSDP discovery succeeds, but command/response fails.

Solution:

  • Check port 1400 TCP is allowed (Rule 8)
  • Verify IP group “Sonos_Devices” contains correct IPs
  • Check “Auto Allow Return Traffic” is enabled on Rule 8
  • Verify Rules 9, 10, 11 for callback ports

Issue 3: Works Initially, Then Stops

Diagnosis: Dynamic IP changed or mDNS cache stale.

Solution:

  • Confirm static DHCP reservations are configured
  • Restart Sonos app
  • Power cycle Sonos speakers
  • Clear Sonos app cache (Settings → App Preferences → Reset App)

Issue 4: Spotify Connect Doesn’t Work

Diagnosis: Rule 18 (Port 4070) may be needed.

Solution:

  • Test Spotify through Sonos app (should work without Rule 18)
  • If you need Spotify app → Sonos direct control, add Rule 18
  • Remember: Rule 18 allows incoming internet traffic (security consideration)

Issue 5: No Discovery at All

Diagnosis: mDNS or IGMP not configured properly.

Solution:

  1. Verify mDNS enabled on BOTH VLANs
  2. Check IGMP Snooping enabled on BOTH VLANs
  3. Verify Rules 2 & 3 (IGMP) are configured with IPv4 (not Both)
  4. Check multicast addresses in Rules 4-7 (224.0.0.251 and 239.255.255.250)
  5. Temporarily disable Rule 19 (Block IoT) to eliminate it as a variable

What Works After This Configuration

✅ Fully Functional Features

  • Sonos App Control – Full control from iOS/Android/Desktop apps on VLAN 192
  • AirPlay 2 – Direct streaming from Apple devices, including multi-room
  • Multi-Room Audio – Grouping and synchronized playback
  • Music Services – Spotify, Apple Music, Amazon Music, Tidal, etc. (through Sonos app)
  • Spotify Connect – Direct control from Spotify app (if Rule 18 enabled)
  • TuneIn Radio – Internet radio stations
  • Voice Assistants – Alexa, Google Assistant (if configured)

⚠️ Potentially Limited Features

  • iOS Lock Screen Controls – May be limited with cross-VLAN setup
  • Sonos S1 App – Older app may require different ports (not tested in this configuration)
  • Sonos Era 100/300 with Recent Firmware – Post-October 2024 firmware has known PTP issues across VLANs
  • Adding New Devices After VLAN Separation – Not tested; recommend configuring devices on single VLAN first
  • Local Music Library via SMB2/3 – Not tested in this configuration; may require additional firewall rules for SMB access

🔒 Security Considerations

What you’ve achieved:

  • ✅ Isolated IoT devices from trusted network
  • ✅ Explicit allow-listing of required traffic only
  • ✅ Blocked all other IoT → LAN traffic
  • ✅ Granular control over specific Sonos devices by IP

What you’ve compromised:

  • ⚠️ Rule 18 (if enabled): Allows incoming internet traffic to Sonos
  • ⚠️ High port ranges (30000-65535): Larger attack surface than specific ports
  • ⚠️ Complexity: More rules = more potential for misconfiguration

Risk assessment: Even with these rules, Sonos speakers remain relatively low-risk IoT devices. The primary benefit is defense in depth and principle of least privilege, not mitigating a specific Sonos vulnerability.

Performance Impact

Network Overhead

Native mDNS Reflection:

  • Minimal CPU impact on UDM Pro (<1% CPU)
  • Small increase in network broadcast traffic
  • Negligible for home networks

Additional firewall rules:

  • No measurable performance impact
  • Modern UniFi hardware handles thousands of rules efficiently

Real-World Testing Results

In the test environment (6 Sonos speakers, 3 controllers):

  • Discovery time: 2-5 seconds (same as single VLAN)
  • Control latency: No perceptible difference
  • Audio streaming: No quality degradation
  • Multi-room sync: Perfect synchronization maintained

Conclusion: When properly configured, cross-VLAN Sonos performs identically to same-VLAN operation.

Maintenance & Updates

After Firmware Updates

UDM Pro firmware updates typically preserve:

  • Firewall rules
  • mDNS configuration
  • IGMP settings
  • Network settings

After each UDM Pro update, verify:

1. Check mDNS is still enabled
Settings → Networks → [VLAN] → Advanced → mDNS

1. Check IGMP snooping
Settings → Networks → [VLAN] → Advanced → IGMP Snooping

1. Test Sonos discovery
Open Sonos app → Verify all speakers discovered

Adding New Sonos Speakers

Recommended process:

  1. Initial setup on single VLAN:

    • Temporarily move your controller to the IoT VLAN, OR
    • Temporarily move new speaker to Private VLAN
    • Complete initial Sonos setup
    • Update firmware if needed

  2. Add static DHCP reservation for new speaker in IoT VLAN

  3. Update IP group “Sonos_Devices” with new speaker's IP

  4. Move device to final location (IoT VLAN if doing initial setup on Private)

  5. Test discovery from Sonos app on Private VLAN

That's it! Firewall rules automatically apply to the IP group.

Note: Adding devices directly on the IoT VLAN after separation was not tested in this configuration.

Removing This Configuration

To return to a single-VLAN setup:

  1. Move Sonos speakers to same VLAN as controllers
  2. Delete firewall Rules 1-19
  3. Disable mDNS on IoT VLAN (or delete VLAN entirely)
  4. Remove static DHCP reservations (optional)

Sonos should immediately discover all speakers without any configuration.

Conclusion: Was It Worth It?

Honestly: Probably not.

This setup required hours of configuring 19 firewall rules, testing various scenarios, and documenting every detail. The result? Sonos works exactly the same as it would on a single VLAN.

Gains:

  • ✅ Technical knowledge about cross-VLAN multicast
  • ✅ Proof that it's possible
  • ✅ A documented reference for future VLAN projects
  • ✅ Slightly better network segmentation (marginal security benefit)

Losses:

  • ⏰ 2-4 hours of configuration time
  • 🧠 Mental overhead of maintaining complex firewall rules
  • 🔧 Ongoing maintenance after firmware updates
  • 😤 Potential troubleshooting when something breaks

The simple alternative: Put Sonos and controllers on the same VLAN. It just works. No configuration, no troubleshooting, no maintenance.

When This Configuration Makes Sense

Consider this setup if you:

  • Are required by policy to segment IoT devices (corporate environment)
  • Enjoy complex networking and want to learn about multicast routing
  • Have a highly segmented network for other reasons and don't want to compromise
  • Value the challenge more than the outcome

When to Skip This Entirely

Keep everything on one VLAN if you:

  • Just want to listen to music without network engineering
  • Don't have specific security requirements for IoT segmentation
  • Aren't familiar with VLANs, firewall rules, and multicast protocols
  • Value simplicity over complexity

Final Thoughts

This guide proves that technical challenges can be overcome with sufficient determination and documentation. Cross-VLAN Sonos is entirely possible with the right configuration.

But here's the paradox: The easier technology becomes to use, the more complex it becomes to secure. Sonos was designed for zero-configuration networking. It works flawlessly when you don't fight against that design. Forcing it into a segmented network requires fighting against its fundamental architecture.

Is that fight worth it? For most people, absolutely not. But for those who enjoy the journey more than the destination, or who have legitimate requirements for network segmentation, this guide provides a complete roadmap.

Remember: The best security configuration is one you understand and can maintain. If this guide seems overwhelming, there's no shame in keeping things simple. Sometimes the most secure network is one that “just works” because you fully understand it.

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