Dedicated Bedrock server LAN discovery broken in 1.21.132.x

Title

Dedicated Bedrock server LAN discovery broken in 1.21.132.x (client receives pong but server never appears in UI)

Platform(s)

• Windows Bedrock client

• Xbox Bedrock client

• Ubuntu 22.04 dedicated Bedrock server

Version

Client: 1.21.132.x

Server: 1.21.132.x (also tested older server versions)

Description

Dedicated Bedrock servers no longer appear via LAN discovery, even though UDP discovery packets are exchanged successfully.

Direct IP connection works normally, but LAN servers never show under Worlds or Servers.

This affects both Windows and Xbox clients.

Steps to Reproduce

1. Set up a dedicated Bedrock server (Ubuntu 22.04) on local network

2. Enable default LAN visibility (enable-lan-visibility=true)

3. Place client and server on same subnet (/24) and same VLAN

4. Start server

5. Open Minecraft Bedrock client

6. Go to Play → Worlds or Play → Servers

7. Observe that LAN server never appears

Expected Result

Dedicated server should appear under LAN Games or similar section, allowing join without manual IP entry.

Actual Result

Server never appears in UI.

However:

• Client sends UDP discovery packets to port 19132

• Server receives packets and replies with valid MCPE pong payload

• Client NIC receives reply

• Server is joinable via direct IP

So discovery works at protocol level, but client UI silently drops the result.

Additional Technical Details

Confirmed via tcpdump on server:

Client broadcast:

client_ip → server_ip:19132 (UDP discovery)

Server reply:

server_ip:19132 → client_ip (UDP pong, length ~114 bytes)

Payload contains valid fields including:

• Protocol

• Version

• World name

• Game mode

• Player counts

• Port

Example payload (ASCII portion):

MCPE;;898;1.21.132;0;10;...;WorldName;Survival;1;19132;65535;0;

Client receives reply but does not render server in UI.

What Has Already Been Tried

• Fresh OS rebuild (moved from VM to brand new LXC container)

• Fresh Bedrock server install

• Downgrading server binaries

• Same subnet + same VLAN

• Server firewall disabled (UFW/nftables/iptables empty)

• Proxmox firewall disabled

• Confirmed UDP traffic flows both directions

• Confirmed server responds correctly

• Confirmed direct IP join works

• Tested on both Windows and Xbox clients

Issue persists in all cases.

Workarounds

• Manual server add works on PC

• Xbox requires DNS redirect / BedrockConnect-style workaround

LAN discovery itself appears broken for dedicated servers.

Suspected Cause

Client-side regression in Bedrock 1.21.132.x LAN discovery rendering.

Discovery protocol works, UI silently drops