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

I was having this same problem when trying to dump my database info from mLab. It was happening because I had mongo 2.x locally and 3.x in mLab. Upgrading my local mongo to the same major version as mLab allowed me to do the dump, thus solving the problem.

Answer 2

If you use the --uri option, you need to add authSource=admin as a parameter to your connection string (assuming your user is on the admin database)

mongodump --uri="mongodb://user:pass@host1:27017,host2:27017,host3:27017/?replicaSet=rs0"

Becomes:

mongodump --db=test --uri="mongodb://user:pass@host1:27017,host2:27017,host3:27017/?replicaSet=rs0&authSoource=admin"