MongoDB logging all queries

The question is as basic as it is simple... How do you log all queries in a "tail"able log file in mongodb?

I have tried:

• setting the profiling level
• setting the slow ms parameter starting
• mongod with the -vv option

The /var/log/mongodb/mongodb.log keeps showing just the current number of active connections...

You can log all queries:

$ mongo
MongoDB shell version: 2.4.9
connecting to: test
> use myDb
switched to db myDb
> db.getProfilingLevel()
0
> db.setProfilingLevel(2)
{ "was" : 0, "slowms" : 1, "ok" : 1 }
> db.getProfilingLevel()
2
> db.system.profile.find().pretty()

Source: http://docs.mongodb.org/manual/reference/method/db.setProfilingLevel/

db.setProfilingLevel(2) means "log all operations".

I ended up solving this by starting mongod like this (hammered and ugly, yeah... but works for development environment):

mongod --profile=1 --slowms=1 &

This enables profiling and sets the threshold for "slow queries" as 1ms, causing all queries to be logged as "slow queries" to the file:

/var/log/mongodb/mongodb.log

Now I get continuous log outputs using the command:

tail -f /var/log/mongodb/mongodb.log

An example log:

Mon Mar  4 15:02:55 [conn1] query dendro.quads query: { graph: "u:http://example.org/people" } ntoreturn:0 ntoskip:0 nscanned:6 keyUpdates:0 locks(micros) r:73163 nreturned:6 reslen:9884 88ms