Is there a way to increase db connection in mongo without resarting the mongod

Mongo version we are using is 2.4.5 .
solution we found was restarting the server with adding connection limit in mongo conf or giving command line  paramenter.



The maximum is 20,000 in the version you're using, it's also the
default.   It has no effect to try to raise it above that - your limit
will be your OS limit, essentially.

Can you explain why you feel you need to raise it?   Most likely there
is a different way to achieve what you are trying to do.



The maximum number of connections is controlled by --maxConns on the command line or net.maxIncomingConnections in the configuration file. Changing either of these requires a restart of mongod, so changing the max connections requires a restart of mongod.



current limit is 1024 wanted to raise it to ~2k as the number of clients have increased


When you say 

> current limit is 1024

That is NOT a limit in MongoDB itself anywhere.   Are you referring to some OS setting (like maybe your ulimits are set too low?)