The code below is what I'm receiving when I try to connect to database to launch the RapidMiner ser

figs

at java.awt.EventDispatchThread.pumpEvents(Unknown Source)

at java.awt.EventDispatchThread.run(Unknown Source)

Caused by: java.net.ConnectException: Connection refused: connect

at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)

at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)

at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)

at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)

at java.net.AbstractPlainSocketImpl.connect(Unknown Source)

at java.net.PlainSocketImpl.connect(Unknown Source)

at java.net.SocksSocketImpl.connect(Unknown Source)

at java.net.Socket.connect(Unknown Source)

at org.postgresql.core.PGStream.<init>(PGStream.java:75)

at org.postgresql.core.v3.ConnectionFactoryImpl.tryConnect(ConnectionFactoryImpl.java:91)

at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:192)

... 46 more

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Accepted answers

Marco_Barradas

@figs it means that the variable has not been created yet. You need to install the latest java version to you computer.

And then define the variable following the steps on the link I provided.
Depending on your computer the java file might be under C:\ProgramData\Oracle\Java

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Marco_Barradas

hi @figs it says your connection was refused please check all of the following

Type of Database and port
User has permissions on the DB you are going to use
Password confirm the password you entered
If the DB is on another server check if both server can see each other through you network

I see you are using postgresql as DB maybe @rfuentealba or @BalazsBarany could help us if you paste more details on the error.

BalazsBaranyRM

Hi,

thanks @MarcoBarradas. The "Connection refused" error is before any authentication. The database simply doesn't listen on the address you're connecting to.

PostgreSQL is usually configured to listen on localhost (127.0.0.1) by default. This means that you can't reach it from an external computer. This is a security measure for installations where the application runs on the database server itself (e. g. a web server).
If you want the database to listen on public addresses, you need to change the listen_addresses setting in postgresql.conf and restart the database server.

Regards,
Balázs

figs

Thanks guys. Im not use to Java. How do I change the address settings in postsql?

BalazsBaranyRM

Hi @figs,

RapidMiner is written in Java, so you are using it.

I described exactly how to change the listening address in the PostgreSQL configuration. If this is too terse for you, check the PostgreSQL documentation, it's really verbose and well written.

Regards,
Balázs

figs

Image: https://us.v-cdn.net/6030995/uploads/editor/cm/eeivscwfgh8e.jpg

figs

This is what I'm getting when I try to download rapidMiner server...what does JAVA PATH: Null

Marco_Barradas

Hi @figs if you are under Windows you need to create a enviroment variable call Java Path that will point to the place in which your java bin files are.
Here you can find how to do it on different OS https://explainjava.com/java-path/

figs

Does Null mean it couldnt find the java file?

figs

Im also using windows 10

Marco_Barradas

figs

I downloaded the latest jre version 8 from Oracle. It detected old versions of Java and removed them