server.properties

Modify the running configuration of the server to customize some basic functionalities.

These are the standard Minecraft server settings defined in server.properties. For advanced Nukkit-MOT settings, see nukkit-mot.yml.

motd

Data Type	Default Value
String	Minecraft Server

server name / text which shows on the server list

note

can't be empty

sub-motd

Data Type	Default Value
String	Powered by Nukkit-MOT

second line for motd

note

shows only for players in local network when viewing the server on the friends list in game

can't be empty since 1.16.210

server-port

Data Type	Default Value
Integer	19132

server's port

note

there can't be two servers running in the same port

you will need to port forward in order to have your server publicly accessible

bedrock edition uses UDP

when NetherNet is enabled, the same port also serves the WebRTC signaling over TCP, so open the port for TCP as well

server-ip

Data Type	Default Value
String	0.0.0.0

server's IP address

note

there can't be two servers running in the same port

you will need to port forward in order to have your server publicly accessible

bedrock edition uses UDP

this address binds both the RakNet UDP listener and the NetherNet TCP signaling

server-udp-ports

Data Type	Default Value
Integer / String	19132

UDP port for NetherNet (WebRTC) media, using the same syntax as Bedrock Dedicated Server:

Value	Description
19132	Media shares server-port's UDP side with RakNet, relayed in-process from the RakNet socket (default — nothing extra to open or forward)
0	Media ports are system-assigned per connection
N	Pin a standalone media port, e.g. 19134 (one ICE mux port serves all peers)
A-B	Pin a window of media ports
[ip:]external[-external]:internal[-internal]	Also publish an external port mapping, e.g. behind NAT. Both ranges must have the same length

Entries may carry an IP prefix ([2001:db8::1]:... for IPv6) and multiple comma-separated entries accumulate advertised IPs while the window and offset must agree.

Sharing works when a single port is pinned exactly on server-port or the IPv6 listener port, or mapped onto one of them as a single-port mapping — 19132:50000 publishes the media on 19132 while relaying from the internal port 50000. The media then arrives on the RakNet socket and is relayed in-process to a loopback port.

warning

Port windows must not cover server-port (its UDP side belongs to RakNet) or the IPv6 listener port — only a single pinned port or a single-port mapping may share them. Invalid values abort startup instead of falling back to automatic ports.

Media UDP unreachable — players hang on join

When NetherNet players hang on "Connecting" or drop right after joining, the media UDP path is blocked. The server reports this on its own — the log warns:

NetherNet media may be unreachable: 6 ICE attempts, 0 connected in the last 5 minutes.
Check the firewall/port forwarding for the media UDP window udp/... (server-udp-ports)

and /status shows joins accepted while ICE connected stays 0.

Fix it like this:

1. Allow the media UDP port inbound — host firewall, cloud security group and router port forwarding alike. With the default the media shares server-port's UDP side (19132), which RakNet already needs open — nothing extra to allow; a standalone pinned port (e.g. server-udp-ports=19134) must be opened/forwarded explicitly, and only with server-udp-ports=0 are the ports system-assigned and unpredictable — pin a window first (e.g. server-udp-ports=50000-50010) and forward that
2. Public ports differ from the internal ones (NAT mapping)? Publish the external side instead: server-udp-ports=60000-60010:50000-50010
3. Still failing for players behind symmetric NAT? Relay the media through a TURN server configured in network-settings.nethernet.ice-servers:

network-settings:
  nethernet:
    ice-servers:
      - stun:stun.l.google.com:19302
      - 'turn:user:pass@turn.example.com:3478?transport=udp'

Diagnosing by the /status numbers

• Joins accepted rising while ICE connected stays 0 — media UDP is blocked; apply the steps above
• ICE connected rising but few handshakes completed — the DTLS handshake fails, usually a middlebox interfering with UDP
• Many drops after connect — NAT timeouts or connection jitter

server-ipv6-port

Data Type	Default Value
Integer	-1

port for the optional IPv6 listener

note

the IPv6 listener is disabled when this is 0 or lower (default -1)

to enable it, set a valid port that differs from server-port

server-ipv6

Data Type	Default Value
String	::

IPv6 address the optional IPv6 listener binds to

must be a valid IPv6 address; leave blank to disable the IPv6 listener

view-distance

Data Type	Default Value
Integer	8

maximum view distance in chunks

bigger value = more chunks loaded = more ram & cpu usage

max-players

Data Type	Default Value
Integer	50

Maximum number of players allowed on the server

language

Data Type	Default Value
String	eng

default language that Nukkit uses

force-language

Data Type	Default Value
Boolean	off

force server side translations to be used

enable only if you have a plugin to implement those

shutdown-message

Data Type	Default Value
String	§cServer closed

message that shows for players when you stop the server

use § for colors and §n for new line

gamemode

Data Type	Default Value
Integer	0

server's default gamemode

0 = survival, 1 = creative, 2 = adventure, 3 = spectator

force-gamemode

Data Type	Default Value
Boolean	on

set player gamemode to default gamemode on every join

difficulty

Data Type	Default Value
Integer	2

server's default difficulty (0-3)

hardcore

Data Type	Default Value
Boolean	off

players will be banned when they die

pvp

Data Type	Default Value
Boolean	on

Whether to enable player versus player combat

level-name

Data Type	Default Value
String	world

Name of the default world

level-seed

Data Type	Default Value
String

Seed for the default level

level-type

Data Type	Default Value
String	default

generator used to create the default level if it doesn't exist

supported by default: default, normal, flat, nether, the_end or void

generator-settings

Data Type	Default Value
String

Special world generator settings for the default level

spawn-protection

Data Type	Default Value
Integer	10

size of the spawn area in blocks where non op players can't build or break blocks

white-list

Data Type	Default Value
Boolean	off

allow only players on the whitelist to join the server

use /whitelist command or modify white-list.txt to add players to whitelist

whitelist-reason

Data Type	Default Value
String	§cServer is white-listed

Reason for enabling the whitelist, displayed to players when they are denied access

xbox-auth

Data Type	Default Value
Boolean	on

require Xbox account to join

note

does not bypass client side requirements

if you disable this (not recommended), install a login plugin to protect player account security

keep-existing-session-on-duplicate-login

Data Type	Default Value
Boolean	off

keep the session that is already playing when a duplicate login arrives

by default a new login with the same name or identity kicks the player that is already online; enable this to refuse the newcomer instead, so a player who is carrying loot cannot be evicted by someone reusing the nickname

a stale session still times out by itself

encryption

Data Type	Default Value
Boolean	on

enable network encryption for RakNet sessions

it's recommended to enable this if you don't use a proxy software

note

NetherNet sessions are always DTLS-secured, regardless of this option.

force-resources

Data Type	Default Value
Boolean	off

force players to download server's resource pack if they want to join

force-resources-allow-client-packs

Data Type	Default Value
Boolean	off

don't disable client's own packs when force-resources is enabled

spawn-animals

Data Type	Default Value
Boolean	on

enable animal spawning

spawn-mobs

Data Type	Default Value
Boolean	on

enable monster spawning

allow-flight

Data Type	Default Value
Boolean	off

enable / disable allowing players to fly

note

if players are often kicked for flying, try setting this to on

auto-save

Data Type	Default Value
Boolean	on

automatically save the world and player data

note

if disabled, changes to worlds are not saved automatically even on unload, use plugin to save manually if needed

enable-rcon

Data Type	Default Value
Boolean	off

enable remote console access

note

rcon isn't very secure way to remote control the server

rcon uses the same port (but TCP) as the server

See: https://developer.valvesoftware.com/wiki/Source_RCON_Protocol

rcon.password

Data Type	Default Value
String	Random 10 characters

Password for RCON connections

rcon.port

Data Type	Default Value
Integer	25575

Port for RCON connections

enable-query

Data Type	Default Value
Boolean	on

enable extended query

server-authoritative-movement

Data Type	Default Value
String	server-auth

Server authoritative movement

Optional: client-auth / server-auth-with-rewind / server-auth

server-authoritative-block-breaking

Data Type	Default Value
Boolean	on

Server authoritative block breaking

server-authoritative-inventory

Data Type	Default Value
Boolean	on

Server authoritative inventory transactions (ItemStackRequest)

only takes effect for clients on protocol 1.16.100 and above

note

this is the inventory equivalent of server authoritative movement — the server validates item moves instead of trusting the client