mongodb service is not starting up
This can also happen if your file permissions get changed somehow. Removing the lock file didn't help, and we were getting errors in the log file like:
2016-01-20T09:14:58.210-0800 [initandlisten] warning couldn't write to / rename file /var/lib/mongodb/journal/prealloc.0: couldn't open file /var/lib/mongodb/journal/prealloc.0 for writing errno:13 Permission denied
2016-01-20T09:14:58.288-0800 [initandlisten] couldn't open /var/lib/mongodb/local.ns errno:13 Permission denied
2016-01-20T09:14:58.288-0800 [initandlisten] error couldn't open file /var/lib/mongodb/local.ns terminating
So, went to check permissions:
ls -l /var/lib/mongodb
total 245780
drwxr-xr-x 2 mongodb mongodb 4096 Jan 20 09:14 journal
drwxr-xr-x 2 root root 4096 Jan 20 09:11 local
-rw------- 1 root root 67108864 Jan 20 09:11 local.0
-rw------- 1 root root 16777216 Jan 20 09:11 local.ns
-rwxr-xr-x 1 mongodb nogroup 0 Jan 20 09:14 mongod.lock
To fix:
# chown -R mongodb:mongodb /var/lib/mongodb
Remove the lock file if it's still there:
# rm /var/lib/mongodb/mongod.lock
Start mongodb
# service mongodb start
Tail the log and you should see at the end of it:
tail -f /var/log/mongodb/mongodb.log
2016-01-20T09:16:02.025-0800 [initandlisten] waiting for connections on port 27017
I was bored of this problem so I decided to create a shell script to restore my mongo data base easily.
#!/bin/sh
sudo rm /var/lib/mongodb/mongod.lock
sudo -u mongodb mongod -f /etc/mongodb.conf --repair
sudo service mongodb start
http://ideone.com/EuqDZ8
On my ubuntu server, just run:
sudo rm /var/lib/mongodb/mongod.lock
mongod --repair
sudo service mongodb start
Fixed!
The reason was the dbpath variable in /etc/mongodb.conf.
Previously, I was using mongodb 1.8, where the default value for dbpath was /data/db.
The upstart job mongodb(which comes with mongodb-10gen package) invokes the mongod with --config /etc/mongodb.conf option.
As a solution, I only had to change the owner of the /data/db directory recursively.