Could not connect to mongod from mongo shell when auth enabled (on ubuntu) - node.js

Question

System: ubuntu 14.04
mongodb 3.0.3 tar ball is downloaded from mongodb download center
connected to mongodb without auth, then from mongo shell, created a user for 'test' db. following is the command.
db.createUser({user: "user1",
pwd: "test123",
roles: [ { role: "readWrite", db: "test" }
]})
Verified that user details in admin db. Following is the command & result:
> db.system.users.findOne({user:'user1'})
{
"_id" : "testdb.user1",
"user" : "user1",
"db" : "testdb",
"credentials" : {
"SCRAM-SHA-1" : {
"iterationCount" : 10000,
"salt" : "kNfOd1vs+QT+ueH7SI6Vzw==",
"storedKey" : "JCesIKSW1pb74ddo2Y19rEO1GVY=",
"serverKey" : "d87Sb1htoD5K8zecAy73JPZyHdc="
}
},
"roles" : [
{
"role" : "readWrite",
"db" : "test"
}
]
}
Now exit from the mongo shell, killed the mongod.
Started the mongodb with auth, following is the command.
$ ./mongod --auth
Connected to mongo shell as usual, see the below:
$ ./mongo
MongoDB shell version: 3.0.3
connecting to: test
> show collections
2016-05-11T22:33:46.302+0530 E QUERY Error: listCollections failed: {
"ok" : 0,
"errmsg" : "not authorized on test to execute command { listCollections: 1.0 }",
"code" : 13
}
at Error (<anonymous>)
at DB._getCollectionInfosCommand (src/mongo/shell/db.js:646:15)
at DB.getCollectionInfos (src/mongo/shell/db.js:658:20)
at DB.getCollectionNames (src/mongo/shell/db.js:669:17)
at shellHelper.show (src/mongo/shell/utils.js:625:12)
at shellHelper (src/mongo/shell/utils.js:524:36)
at (shellhelp2):1:1 at src/mongo/shell/db.js:646
> db.auth({user:'user1', pwd:'test123'})
1
> use test
switched to db test
> db.collone.insert({name:'firstcollection'})
WriteResult({ "nInserted" : 1 })
> show collections
collone
system.indexes
> db.collone.find()
{ "_id" : ObjectId("5733669fb7d44cd444ebf028"), "name" : "firstcollection" }
> exit
bye
When i tried to do the authentication while starting the mongo shell, getting authentication failed error. See below:
$ ./mongo test -u 'user1' -p 'test123' --authenticationDatabase 'admin'
MongoDB shell version: 3.0.3
connecting to: test
2016-05-11T22:37:21.559+0530 E QUERY Error: 18 Authentication failed.
at DB._authOrThrow (src/mongo/shell/db.js:1266:32)
at (auth):6:8
at (auth):7:2 at src/mongo/shell/db.js:1266
exception: login failed
All this is just a POC that i'm trying to do.
Once it's success, my target is to connect from mongoose client(from Node.js app) to mongod.
The following command from a stackoverflow post can help me to set up connection from mongoose to mongod with auth.