使用mongodump：

$ ./mongodump --host prod.example.com
connected to: prod.example.com
all dbs
DATABASE: log    to   dump/log
        log.errors to dump/log/errors.bson
                713 objects
        log.analytics to dump/log/analytics.bson
                234810 objects
DATABASE: blog    to    dump/blog
        blog.posts to dump/log/blog.posts.bson
                59 objects
DATABASE: admin    to    dump/admin

来源：http
://www.mongodb.org/display/DOCS/Import+Export+Tools