Connectivity Problem with Minecraft Bedrock - Bedrock server UDP responses not reaching clients

Technical Support
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1

System Information

Field Value
Operating System Linux - Debian GNU/Linux 13 on x86_64
Product AMP ‘Deimos’ v2.7.2.8 (Mainline)
Virtualization Docker
Application Minecraft Bedrock
Module GenericModule
Running in Container Yes
Current State Ready

Problem Description

Issue

I am hosting a Minecraft Bedrock dedicated server on this VPS. The server starts correctly, loads the world, and binds to UDP port 19132 without any errors. The Bedrock server reports “Server started” and appears to be functioning normally.

However, external clients cannot connect to the server even though the port is open and reachable. To diagnose the issue, I performed a packet capture on the VPS using tcpdump.

The results show that inbound UDP packets from the client reach the VPS normally. Outbound UDP packets are also sent, but they are always exactly 33 bytes in length. This is the size of the initial RakNet ping, not the full Bedrock response packet. A proper Bedrock server should send a larger response packet of around 140 to 180 bytes containing the server information and MOTD.

Because only the small 33 byte packets leave the VPS, the required Bedrock response packet never reaches the client. As a result, the Minecraft client cannot complete the handshake and cannot connect to the server.

This behavior strongly suggests that larger outbound UDP packets on port 19132 are being blocked, filtered, or truncated by an upstream network rule, firewall policy, or virtualization layer within Hostinger’s infrastructure.

Evidence:

The server is listening on UDP 19132

Inbound UDP packets arrive normally

Outbound packets are always 33 bytes instead of the expected larger Bedrock response

Clients cannot connect because they never receive the required response packet

Request:
Please verify whether full UDP passthrough is enabled on this VPS and whether any upstream filtering, NAT rules, anti DDoS policies, or packet size restrictions are affecting UDP traffic on port 19132. Minecraft Bedrock requires unfiltered bidirectional UDP traffic to function correctly.

Reproduction Steps

  • Deploy a Minecraft Bedrock dedicated server on the VPS using the default installation method provided by Hostinger.
  • Start the Bedrock server and confirm that it is running and listening on UDP port 19132 using standard Linux networking tools.
  • Attempt to connect to the server from an external device such as a phone or computer using the public IP and port 19132.
  • Run a packet capture on the VPS to monitor UDP traffic on port 19132 while attempting to connect from the external device.
  • Observe that inbound UDP packets from the client reach the VPS normally but outbound packets from the server are always only 33 bytes in size.
  • Confirm that the Minecraft client cannot connect because it never receives the larger Bedrock response packet that is required for the connection process.
2

Because of a client version mismatch I opened the AMP interface and updated AMP and Minecraft Bedrock and now am unable to connect, just times out so could be the same problem?

BTW I’m running a dedicated server over a LAN at home!

3

I got a workaround on another thread in case someone can benefit from this. At least we can get 1 working bedrock server.

:star: What “Enable LAN Visibility” actually does

When Enable LAN Visibility = true, the Bedrock server:

1. Starts sending LAN broadcast beacons

These are small UDP packets sent to the client’s IP directly.

2. Switches to a different RakNet handshake path

The LAN handshake is smaller, simpler, and uses different packet sizes.

3. Sends smaller UDP response packets

These packets are below the size threshold that Hostinger is filtering.

4. Does NOT send the full MOTD response packet

The MOTD packet is the one Hostinger was blocking.

So with LAN visibility ON, the server avoids sending the large packet that Hostinger was dropping.

:star: Why this makes your server suddenly work

Your earlier tcpdump showed:

  • Inbound packets: 33 bytes

  • Outbound packets: 33 bytes

But a real Bedrock server should send a ~150 byte response.

Hostinger was blocking that larger packet.

When you enable LAN visibility:

:check_mark: The server stops sending the large MOTD packet

:check_mark: It sends only the small LAN beacon packets

:check_mark: Those packets are small enough to pass through Hostinger’s filtering

:check_mark: Your client receives something, so the connection succeeds

In other words:

LAN mode avoids the packet that Hostinger was blocking.

:star: Why this is NOT a real fix

LAN visibility mode is not designed for internet servers.

It:

  • Reduces compatibility

  • Can break cross‑platform connections

  • May fail for players far away

  • Is not guaranteed to work consistently

  • Is not how Bedrock servers are meant to operate publicly

It’s basically a workaround that works only because Hostinger is filtering the normal packets.

:star: The real underlying issue remains:

Hostinger is still blocking or truncating large outbound UDP packets.

LAN mode just happens to use smaller packets.