Can't create backup mongodump with --db. Authentication failed

Question

When I create backup of all databases in MongoDB (version 3):

mongodump --username bacUser --password 12345

It\'s OK. But when I try to cre

Answer 1

If you are using mLab then it could be the version in your local mongo is not match with mLab. By default, Ubuntu will install mongo v2.x and mLab is v3.x. You could check with this command:

mongo --version

Install new mongo version:

1. Remove your old local mongo (be careful, it may remove all your local database)

sudo apt remove mongo-clients mongodb

2. Import the public key used by the package management system.

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv D68FA50FEA312927

3. Create a list file for MongoDB.

   • Ubuntu 14.04

echo "deb http://repo.mongodb.org/apt/ubuntu trusty/mongodb-org/3.2 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-3.2.list

• Ubuntu 16.04

echo "deb http://repo.mongodb.org/apt/ubuntu xenial/mongodb-org/3.2 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-3.2.list

4. Install the MongoDB packages

sudo apt-get install -y mongodb-org

Ref: https://docs.mongodb.com/v3.2/tutorial/install-mongodb-on-ubuntu/

Now you can dump your database with this command:

mongodump -h : -d  -u  -p  -o