MongoDB shell version error (Server has startup warnings)
I don't believe there is a way to suppress only that warning, but you can always start your mongod instance with the --quiet flag.


  --quiet Runs the mongod instance in a quiet mode that attempts to limit the amount of output. This option suppresses:
  
  
  output from database commands, including drop, dropIndexes,
  diagLogging, validate, and clean. replication activity. connection
  accepted events. connection closed events.
  





  Reference - http://docs.mongodb.org/manual/reference/program/mongod/#cmdoption--quiet


So when you use this flag, you are actually disabling quite a lot of useful information. As you can see from the content of the warning, using the 32bit version will seriously limit the amount of data you will be able to store. I think you should consider upgrading to the 64bit version.