I can start the MongoDB shell, but not Mongo Daemon - mongodb

Question

I'm new to MongoDB, and I'm trying to run mongod. If I type in mongo, I can run the shell (and then I exit nicely with ^C), but when I try typing mongod, I get this:
mongod --help for help and startup options
Sat Nov 24 13:42:34 [initandlisten] MongoDB starting : pid=99910 port=27017 dbpath=/data/db/ 64-bit host=Macbook-err.local
Sat Nov 24 13:42:34 [initandlisten]
Sat Nov 24 13:42:34 [initandlisten] ** WARNING: soft rlimits too low. Number of files is 256, should be at least 1000
Sat Nov 24 13:42:34 [initandlisten] db version v2.2.1, pdfile version 4.5
Sat Nov 24 13:42:34 [initandlisten] git version: nogitversion
Sat Nov 24 13:42:34 [initandlisten] build info: Darwin 172-26-13-128.dynapool.nyu.edu 12.2.0 Darwin Kernel Version 12.2.0: Sat Aug 25 00:48:52 PDT 2012; root:xnu-2050.18.24~1/RELEASE_X86_64 x86_64 BOOST_LIB_VERSION=1_49
Sat Nov 24 13:42:34 [initandlisten] options: {}
Sat Nov 24 13:42:34 [initandlisten] journal dir=/data/db/journal
Sat Nov 24 13:42:34 [initandlisten] recover : no journal files present, no recovery needed
Sat Nov 24 13:42:34 [websvr] ERROR: listen(): bind() failed errno:48 Address already in use for socket: 0.0.0.0:28017
Sat Nov 24 13:42:34 [websvr] ERROR: addr already in use
Sat Nov 24 13:42:34 [initandlisten] ERROR: listen(): bind() failed errno:48 Address already in use for socket: 0.0.0.0:27017
Sat Nov 24 13:42:34 [initandlisten] ERROR: addr already in use
Sat Nov 24 13:42:34 [initandlisten] now exiting
Sat Nov 24 13:42:34 dbexit:
Sat Nov 24 13:42:34 [initandlisten] shutdown: going to close listening sockets...
Sat Nov 24 13:42:34 [initandlisten] shutdown: going to flush diaglog...
Sat Nov 24 13:42:34 [initandlisten] shutdown: going to close sockets...
Sat Nov 24 13:42:34 [initandlisten] shutdown: waiting for fs preallocator...
Sat Nov 24 13:42:34 [initandlisten] shutdown: lock for final commit...
Sat Nov 24 13:42:34 [initandlisten] shutdown: final commit...
Sat Nov 24 13:42:34 [initandlisten] shutdown: closing all files...
Sat Nov 24 13:42:34 [initandlisten] closeAllFiles() finished
Sat Nov 24 13:42:34 [initandlisten] journalCleanup...
Sat Nov 24 13:42:34 [initandlisten] removeJournalFiles
Sat Nov 24 13:42:34 [initandlisten] shutdown: removing fs lock...
Sat Nov 24 13:42:34 dbexit: really exiting now
This seems to be a common problem around here, and I've tried:
deleting the mongod.lock file rm /data/db/mongod.lock
repair: mongod --repair
killing processes: killall -15 mongod and killall -9 mongod
I tried changing permissions: sudo chmod 0755 /data/db and sudo chown $USER /data/db
My permissions seem correct:
drwxr-xr-x 4 slaffont wheel 136 Nov 24 13:28 /data/db/
I've run out of ideas. Has anyone else had this problem? What should I do? :(

Answer 1

From your main comments, it seems you installed MongoDB via macports (given the /opt install location). What I believe might be happening is that the recipe for macports installed MongoDB as a launchd service.
Check this location for a mongodb related plist file: /Library/LaunchDaemons
If you find it, that means your system will automatically keep this service running. If you only want to run the mongod manually, then remove this plist and reboot. Or you can try this command:
launchctl unload /Library/LaunchDaemons/path.to.mongo.plist
Otherwise, run another instance of mongod on a different port.

Answer 2

sudo rm /var/lib/mongodb/mongod.lock
sudo chown -R mongodb:mongodb /var/lib/mongodb/
sudo -u mongodb mongod -f /etc/mongodb.conf --repair
sudo service mongodb start
or instead of the last one try : sudo mongod

Answer 3

"Address already in use for socket: 0.0.0.0:28017"
It looks like mongo is already running or another process is using port 27017
In this case, type the following command
ps wuax | grep mongo
You should see something that looks like this
User 31936 0.5 0.4 2719784 35624 ?? S 7:34pm 0:09.98 mongod
User 31945 0.0 0.0 2423368 184 s000 R+ 8:24pm 0:00.00 grep mongo
Now enter the kill command for the mongod instance (31936 in this case):
kill 31936

Answer 4

It looks like something is already bound to port 27017, making it seem like another mongod is running (that was not killed on the killall). Does the output of ps aux or lsof -i :27017 show any mongod processes running?
If this proves completely fruitless, you can always pass the --port <portnum> option to the mongod process via the command line, telling it to listen on a different port (use the same option for the mongo shell to tell it to connect on a different port than 27017.

Answer 5

As #shelman said, you already have something using that port, however your command to understand if something is running is wrong, try:
sudo netstat -lpn |grep :27017
I have noticed as well:
Sat Nov 24 13:42:34 [initandlisten] ** WARNING: soft rlimits too low. Number of files is 256, should be at least 1000
This is more of an warning but still one you should heed. I answered a question with some one who had this problem recently: Mongod runs, but Mongo returns an error that should help.

Answer 6

Since this seems to be a common question:
As someone who just had/solved this problem, what you're probably running into is this. When you first install Mongo (say, via apt-get), the Mongod process automatically starts running. For example:
terekhov / $ sudo apt-get install mongodb-10gen
--Snip Install Process--
Done. mongodb
start/running, process 4467 Processing triggers for ureadahead ...
terekhov / $ service mongodb start start: Job is already running: mongodb
So, if you don't need a forked daemon etc, then just type mongo to start the command shell; it will automatically search for a MongoDB daemon on port 27017. Happily, that's where ours is.
You can start/stop/restart the mongod process with this command: sudo service mongodb stop