how to get connected clients in MongoDB

Question

I\'m writing an app using mongo as its db. I want to print the clients connected to the db, for example, print their ip. How can I get that info?

I tried using

Answer 1

You should be able to run this command and get a list of connected IP addresses:

db.currentOp(true).inprog.forEach(function(d){if (d.client)printjson(d.client)})

db.currentOp is actually built on top of the special collection $cmd.sys.inprog so you can also query that directly. You can get an idea of the how to do that by typing in db.currentOp without the parentheses into the mongo shell and it will print out the source for the function:

> db.currentOp
function ( arg ){
    var q = {}
    if ( arg ) {
        if ( typeof( arg ) == "object" )
            Object.extend( q , arg );
        else if ( arg )
            q["$all"] = true;
    }
    return this.$cmd.sys.inprog.findOne( q );
}

Answer 2

This is a bit hacky, but you can actually get this via netstat, even without connecting to the db. This would be done in a (bash) shell script on the DB server. I actually have this in my login script (~/.bash_profile), so that I can easily (& quickly) find network connections into MongoDB and any other service that runs on TCP.

First, you would run this in the shell, which defines a function.

function whoIsConnectedToPort () {
    PORT=$1
    netstat -an | grep ":${PORT}.*ESTAB" | awk '{print $4":"$5}' | cut -d: -f2- | grep "^${PORT}:" | cut -d: -f2 | grep -v '^127' | sort | uniq | xargs -n1 nslookup | grep 'name =' | awk {'print $NF'} | sed 's/.$//' | sort | uniq
}

Then invoke the function.

whoIsConnectedToPort 27017

This should return a list of hosts connected to the given port.

You can reuse it for other familiar ports. Try for example:

whoIsConnectedToPort 22
whoIsConnectedToPort 3306
whoIsConnectedToPort 1521

Answer 3

You can use db.currentOp(true) and iterate over the inprog array of the result set, using the client field.