Question

I’m trying to use command copydb in mongodb.

When I do so I get the following exception:

Command 'copydb' failed: access denied; use admin db (response: { "errmsg" : "access denied; use         
admin db", "ok" : 0.0 })

I have tried to log in as admin but failed because I’m not using username & password.

How do I log in as admin without username & password?
Why do I need to log in as admin if I already have privileges to do drop?

Thanks in advance

m_mongoDatabase.RunCommand(new CommandDocument(new BsonElement("copydb", (BsonValue) 1),
    new BsonElement("fromdb", (BsonValue) from),
    new BsonElement("fromhost", (BsonValue) fromHost),
    new BsonElement("todb", (BsonValue) to)));

Answer 1

I think the problem is that you are not connecting to the “admin” database on the target instance first.

I can perform the operation you require using the following code:

var client = new MongoClient(MongoUrl.Create("mongodb://localhost:27018"));
        var m_mongoDatabase = client.GetServer().GetDatabase("admin");
        var result = m_mongoDatabase.RunCommand(
            new CommandDocument(new BsonElement("copydb", 1),
                new BsonElement("fromhost", "localhost"),
                new BsonElement("fromdb", "sourcedb"),
                new BsonElement("todb", "targetdb")));

Notice that I acquire a ref to the admin database first. When I didn’t do that and used another regular database I got the same error as you.

So to recap, use the admin database for the value of “m_mongoDatabase”

Hope this helps

Edit:This is the same behaviour when using the mongodb shell, so it doesn’t appear to be an issue with the csharpdriver