Configuration

Everything lives in the server folder. The files are created on first start, with comments.

server.properties     server settings
ops.txt               operators (one name per line)
white-list.txt        players allowed when white-list=on
banned-players.txt    banned players
worlds/<name>/        a world, with its world.properties
players/              each player's save (position, inventory, XP...)
plugins/              plugins
plugin_data/<name>/   each plugin's config and data
resource_packs/       resource packs
permissions.json      permission groups and per-player permissions (/perm)
data/                 the server's identity key (do not share)
server.log            log

server.properties

Key	Default	Role
motd	Bedrokia Server	name in the server list
server-port	19132	connection port (TCP), and first UDP port
max-players	20	maximum players
gamemode	survival	survival, creative, adventure (new players)
force-gamemode	off	on: everyone joins in this mode
white-list	off	on: only players in white-list.txt (and ops) can join
xbox-auth	on	verifies Xbox Live accounts. Keep on in production: with off, anyone can use any name
view-distance	8	chunk radius sent to players (2 to 32)
level-name	world	world loaded from worlds/
level-seed	(empty)	seed of a new world
difficulty	normal	peaceful, easy, normal, hard
pvp	on	players can hurt each other
spawn-animals	on	animals spawn
spawn-monsters	on	monsters spawn at night (never in peaceful)
spawn-protection	16	radius around spawn where only ops can build (0 = off)
keep-inventory	off	keep items on death
force-resources	off	players must accept the resource packs
autosave-interval	60	seconds between automatic saves
webrtc-ports	auto	players' UDP ports: auto (server port + max-players + 5) or first-last
check-updates	on	checks every 6 h for a new version and announces it in the console with its link
log-level	info	debug, info, warn, error

Restart the server after a change. An invalid value is reported at startup.

world.properties

Each world has its own worlds/<name>/world.properties:

Key	Role
generator	normal (vanilla terrain and biomes), flat or void
flat-layers	layers of a flat world, bottom to top: bedrock,3*stone,2*dirt,grass_block
flat-biome	biome of flat or void worlds: plains, desert, ice_plains, mushroom_island...
daylight-cycle	on/off: time passes

Changing the generator only affects chunks that were never generated.