we have an EC2 MongoDB 2.4 instance from Amazon MarketPlace. when i try to access it from my computer using the mongo command like so:
mongo xx-xx-xx-xx-xx.c
Try to access xx-xx-xx-xx-xx.compute-1.amazonaws.com:27017 from browser, if it works then ssh into the instance.
/var/lib/mongodb/mongod.lockstart the mongodb server again, and check if typing mongo takes into a mongo shell or gives any error.
If the error is present, exit from the instance and again ssh to check for $mongo, if it opens a mongo shell. Try a reboot after this changes if the error still exists after the above changes.
The only concern here is, before accessing it from any application. Mongodb should work independently in the terminal.