Problem starting MongoDB for the first time (MAC) - mongodb

I tried setting up MongoDB for the first time and I got this error - I recently changed my DNS so I'm not sure if it's related to that. Any ideas what this might mean?
I was following a tutorial on YouTube (Video Here: https://www.youtube.com/watch?v=MIByvzueqHQ). I've seen other entries/issues similar to my one but I believe it might be different. People have said it may be ownership problems. I haven't seen one that says Connection refused - so I will change my DNS back and see if that does anything.
MongoDB shell version v4.0.9
connecting to:
mongodb://127.0.0.1:27017/?gssapiServiceName=mongodb`
2019-07-30T16:14:05.184+1000 E QUERY
`[js] Error: couldn't connect to server 127.0.0.1:27017`,
connection attempt failed: SocketException: Error connecting to `127.0.0.1:27017` :: caused by ::
Connection refused :
`connect#src/mongo/shell/mongo.js:343:13#(connect):2:6
exception: connect failed`
I expected it to start MongoDB so I could give it a test run. This was the only error I saw.

This can happen when the mongodb service is not running on the mac.
To start it, try this:
brew services start mongodb

Related

Mongodb: "Network error while attempting to run command 'getlasterror' on host" when updating data

I update data in mongodb with robo3t and get error: "Network error while attempting to run command 'getlasterror' on host.."
Has anybody got ideas about this?
Check whether you're connected to the primary.
I was having the same issue moments ago and it turned out I had a typo in the domain name of the database server, so I had inadvertently hit the load balancer and reached a non-primary replica.

Issues connecting to an Oracle Database 19c

I am attempting to create and use an oracle DB.
Was able to create the DB using sql plus however when I attempt to connect to it via sqldeveloper I get the following error
Status : Failure -Test failed: IO Error: The Network Adapter could not establish the connection
When I check that all services are running I notice OracleVssWriterORCL is not running.
However upon attempting to start it I get the following error:
Windows could not start OracleVssWriterORCL service on local machine Error 0x80070005: Access is Denied
This is my first time using Oracle for DB so any help is greatly appreciated.
I should also note this is on a windows 10 VM
As stated above my listener was not running and going into cmd using the lsnrctrl start command fixed that issue but now I get a ORA-12505 error. Oh the fun of learning new things

Troubleshoot org.postgresql.util.PSQLException: Connection attempt timed out that only occasionally happens

I have several applications running on tomcat with a local PostgresSQL database. And tomcat occasionally reports the following errors:
org.postgresql.util.PSQLException: Connection attempt timed out.
I am able to connect to the database using other tools such as DBeaver. And this problem looks only happens when several applications are connecting to the database. So I want to know how to troubleshoot this issue. Is there any log in PostgresSQL that I can check?
PostgreSQL does have logging. It is very configurable, and we can't tell you how you have it configured. Common locations are /var/log/postgresql/, and in PGDATA/log/. However, a connection timeout will probably not be in the postgresql log as it probably never achieved contact with the postgresql server to start with.

Cant use mongodb after migrating parse database (using digital ocean migration tutorials)

I have never set up a server myself and I thought that seeing as I have to migrate my parse app I may as well have a go at it.
I have a database that I am moving from Parse to digital ocean. I have a droplet (ubuntu 14.0.4.4 x64) where I log in as a non root user with sudo privileges. I have followed this tutorial to get mongo set up on the droplet.
Then I have followed this tutorial step by step to get the example running on the droplet, which seems to work fine.
Now I am following this tutorial to migrate my existing data over. I have followed the tutorial step by step up to the part where I migrate the data from the parse.com browser. This seems to work fine as I receive the email from Parse saying that "Your Parse Data Migration for Is Ready To Be Finalised!".
The strange thing is, is that when I try to start mongo through terminal I get the error:
MongoDB shell version: 3.0.12
connecting to: test
2016-08-01T19:45:22.383-0400 I NETWORK DBClientCursor::init call() failed
2016-08-01T19:45:22.388-0400 E QUERY Error: DBClientBase::findN: transport error: 127.0.0.1:27017 ns: admin.$cmd query: { whatsmyuri: 1 }
at connect (src/mongo/shell/mongo.js:179:14)
at (connect):1:6 at src/mongo/shell/mongo.js:179
exception: connect failed
As I said I am new to using servers and am relying on these tutorials and hopefully help from the community here.
Thanks for your time

Mongo error: DBClientBase::findN: transport error()

I am facing this error continuously.
DBClientBase::findN: transport error()
I searched the problem and found that there are so many people who faced this problem but didn't find exact reason of this error.
why this error is coming ?
This is probably due to a network error connecting to the mongod server or a mongos cannot connect to the mongod.
The first thing to try in here is to restart the mongod/s
This also occurs if the MongoDB server only accepts SSL encrypted connections. For that you need a MongoDB client compiled with SSL support.
Further readings:
http://docs.mongodb.org/manual/tutorial/configure-ssl-clients/#connect-to-mongodb-instance-with-ssl-encryption
http://www.mongodb.org/about/contributors/tutorial/build-mongodb-from-source/
Mine was resolved by removing SocketTimeOut parameter from the ConnectionString::connect() call.
i.e.
pDBClientBase = cs.connect(strErr /*,2 */);