To take backup of mongodb database
$ monogodb -db database_name > database_name.bson
To restore backup file to database
$ mongorestore -db database_name folder_name
Take backup from heroku MongoHQ using heroku-mongo-sync
$ heroku mongo:pull --app app_name
Take backup from heroku MongoHQ from MongoHQ url
$ mongodump -h hatch.mongohq.com:27021 -d database_name -u admin -p sekret -o ~/tmp/mongodump
Restore heroku MongoHQ database with backup
$ mongorestore -h hatch.mongohq.com:27021 -d database_name -u admin -p sekret ~/tmp/mongodump/database_name