I upgraded my mongodb on ubuntu 16.04 from 3.6 to 4 and now I can't start my mongodb. Only if I run this command sudo mongod `--dbpath /var/lib/mongodb/ --journal` in separate tap and do not close my mongo works. Also I noticed this mongo does not use mongod.conf settings, because authorization is enabled but I still can log in without credentials. Every time when I am trying run mongo without dbpath, appears this error:

MongoDB shell version v4.0.4
connecting to: mongodb://127.0.0.1:27017
2018-11-25T19:12:20.240+0600 E QUERY [js] Error: couldn't connect to server 127.0.0.1:27017, connection attempt failed: SocketException: Error connecting to 127.0.0.1:27017 :: caused by :: Connection refused :
connect@src/mongo/shell/mongo.js:257:13
@(connect):1:6
exception: connect failed