MongoDB shell version v4.0.3
connecting to: .... 
MongoDB server version: 4.0.3
Server has startup warnings:
2018-10-16T09:28:54.524+0200 W CONTROL  [initandlisten]
2018-10-16T09:28:54.524+0200 W CONTROL  [initandlisten]
2018-10-16T09:28:54.524+0200 I CONTROL  [initandlisten]

2018-10-16T09:28:54.484+0200 I STORAGE  [initandlisten] Placing a marker at optime Aug  1 22:26:14:1
2018-10-16T09:28:54.484+0200 I STORAGE  [initandlisten] Placing a marker at optime Aug 27 01:36:54:1
2018-10-16T09:28:54.484+0200 I STORAGE  [initandlisten] Placing a marker at optime Sep 22 01:53:38:1

2018-10-16T09:28:54.674+0200 I FTDC     [initandlisten] Initializing full-time diagnostic data capture with directory '/expldata/ReplicaSet1_4/diagnostic.data'
2018-10-16T09:28:54.675+0200 I REPL     [initandlisten] Rollback ID is 2
2018-10-16T09:28:54.676+0200 I REPL     [initandlisten] Recovering from stable timestamp: Timestamp(1539674864, 1) (top of oplog: { ts: Timestamp(1539674864, 1), t: 30 }, appliedThrough: { ts: Timestamp(0, 0), t: -1 }, TruncateAfter: Timestamp(0, 0))
2018-10-16T09:28:54.676+0200 I REPL     [initandlisten] Starting recovery oplog application at the stable timestamp: Timestamp(1539674864, 1)
2018-10-16T09:28:54.676+0200 I REPL     [initandlisten] No oplog entries to apply for recovery. Start point is at the top of the oplog.