unifi_controller/files/init-mongo.js

db.getSiblingDB("unifi").createUser({user: "unifi", pwd: "unifi", roles: [{role: "readWrite", db: "unifi"}]});
db.getSiblingDB("unifi_stat").createUser({user: "unifi", pwd: "unifi", roles: [{role: "readWrite", db: "unifi_stat"}]});