[ec2-user@ip-172-31-55-219 baby]$ mongod  --directoryperdb --dbpath ./db
2016-06-07T13:42:03.291+0000 I CONTROL  [initandlisten] MongoDB starting : pid=29020 port=27017 dbpath=./db 64-bit host=ip-172-31-55-219
2016-06-07T13:42:03.291+0000 I CONTROL  [initandlisten] db version v3.2.6
2016-06-07T13:42:03.291+0000 I CONTROL  [initandlisten] git version: 05552b562c7a0b3143a729aaa0838e558dc49b25
2016-06-07T13:42:03.291+0000 I CONTROL  [initandlisten] OpenSSL version: OpenSSL 1.0.0-fips 29 Mar 2010
2016-06-07T13:42:03.291+0000 I CONTROL  [initandlisten] allocator: tcmalloc
2016-06-07T13:42:03.291+0000 I CONTROL  [initandlisten] modules: none
2016-06-07T13:42:03.291+0000 I CONTROL  [initandlisten] build environment:
2016-06-07T13:42:03.291+0000 I CONTROL  [initandlisten]     distmod: amazon
2016-06-07T13:42:03.291+0000 I CONTROL  [initandlisten]     distarch: x86_64
2016-06-07T13:42:03.291+0000 I CONTROL  [initandlisten]     target_arch: x86_64
2016-06-07T13:42:03.291+0000 I CONTROL  [initandlisten] options: { storage: { dbPath: "./db", directoryPerDB: true } }
2016-06-07T13:42:03.312+0000 I -        [initandlisten] Detected data files in ./db created by the 'wiredTiger' storage engine, so setting the active storage engine to 'wiredTiger'.
2016-06-07T13:42:03.312+0000 I STORAGE  [initandlisten] wiredtiger_open config: create,cache_size=1G,session_max=20000,eviction=(threads_max=4),config_base=false,statistics=(fast),log=(enabled=true,archive=true,path=journal,compressor=snappy),file_manager=(close_idle_time=100000),checkpoint=(wait=60,log_size=2GB),statistics_log=(wait=0),
2016-06-07T13:42:03.327+0000 E STORAGE  [initandlisten] WiredTiger (-31803) [1465306923:327233][29020:0x7fae5728ad80], txn-recover: Recovery failed: WT_NOTFOUND: item not found
2016-06-07T13:42:03.329+0000 I -        [initandlisten] Assertion: 28595:-31803: WT_NOTFOUND: item not found
2016-06-07T13:42:03.330+0000 I STORAGE  [initandlisten] exception in initAndListen: 28595 -31803: WT_NOTFOUND: item not found, terminating
2016-06-07T13:42:03.330+0000 I CONTROL  [initandlisten] dbexit:  rc: 100