Uninstalled mongodb manually and reinstalled it then mongodb cannot be launched with this error.

gistfile1.txt

2016-02-06T18:10:44.893+0900 I CONTROL  [main] ***** SERVER RESTARTED *****
2016-02-06T18:10:44.910+0900 I CONTROL  [initandlisten] MongoDB starting : pid=46957 port=27017 dbpath=/usr/local/var/mongodb 64-bit host=P23722.local
2016-02-06T18:10:44.910+0900 I CONTROL  [initandlisten] db version v3.2.1
2016-02-06T18:10:44.910+0900 I CONTROL  [initandlisten] git version: a14d55980c2cdc565d4704a7e3ad37e4e535c1b2
2016-02-06T18:10:44.910+0900 I CONTROL  [initandlisten] allocator: system
2016-02-06T18:10:44.910+0900 I CONTROL  [initandlisten] modules: none
2016-02-06T18:10:44.910+0900 I CONTROL  [initandlisten] build environment:
2016-02-06T18:10:44.910+0900 I CONTROL  [initandlisten]     distarch: x86_64
2016-02-06T18:10:44.910+0900 I CONTROL  [initandlisten]     target_arch: x86_64
2016-02-06T18:10:44.910+0900 I CONTROL  [initandlisten] options: { config: "/usr/local/etc/mongod.conf", net: { bindIp: "127.0.0.1" }, storage: { dbPath: "/usr/local/var/mongodb" }, systemLog: { destination: "file", logAppend: true, path: "/usr/local/var/log/mongodb/mongo.log" } }
2016-02-06T18:10:44.911+0900 I STORAGE  [initandlisten] wiredtiger_open config: create,cache_size=4G,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),
2016-02-06T18:10:44.913+0900 E STORAGE  [initandlisten] WiredTiger (2) [1454749844:913596][46957:0x7fff75fbc000], file:WiredTiger.wt, connection: /usr/local/var/mongodb/WiredTiger.wt: No such file or directory
2016-02-06T18:10:44.923+0900 I -        [initandlisten] Assertion: 28595:2: No such file or directory
2016-02-06T18:10:44.923+0900 I STORAGE  [initandlisten] exception in initAndListen: 28595 2: No such file or directory, terminating
2016-02-06T18:10:44.923+0900 I CONTROL  [initandlisten] dbexit:  rc: 100

What I did

rm -rf /usr/local/var/mongodb
brew uninstall --force mongodb
brew install mongodb

<db>.system.namespace has been deprecate since v3.0... https://docs.mongodb.org/manual/reference/system-collections/#%3Cdatabase%3E.system.namespaces

The error message looks like one in this report. https://jira.mongodb.org/browse/SERVER-20729

The major difference between 3.2 and 3.0 is the default storage engine. https://docs.mongodb.org/manual/core/storage-engines/
AFAIK, this problem happened after updating mongodb from 3.0 to 3.2.1 with homebrew then removed the entire db files.

The storage engine of the current my mongodb is wiredTiger 🐯

> db.serverStatus().storageEngine
{ "name" : "wiredTiger", "supportsCommittedReads" : true }

• http://dba.stackexchange.com/questions/96917/check-storage-engine-from-shell/107689#107689

its config file is here:

systemLog:
  destination: file
  path: /usr/local/var/log/mongodb/mongo.log
  logAppend: true
storage:
  dbPath: /usr/local/var/mongodb
net:
  bindIp: 127.0.0.1

Now my application uses an instance hosted by MongLab. its mongodb's version is 3.0.7.
So I'm guessing this problem is caused by using different storage engines between on my Mac and on heroku.

Bingooooooooo 🎉 🎉 🎉

Fixed the problems by specifying storage engine in its configuration file like this.

storage:
  dbPath: /usr/local/var/mongoedb
  engine: mmpav1

• https://docs.mongodb.org/manual/reference/configuration-options/#storage.engine

After this change, restarting a mongodb process is required.

@satoryu I have the same issue, and switching to MMapv1 would not solve my problem, since I already have an existing database.

Do you, by chance, how can I convert my data?

fixed some typos in your snippet @satoryu

storage:
  dbPath: /usr/local/var/mongodb
  engine: mmapv1