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Unable to connect to a Oracle db from Linux machine in java

I have registered a Linux machine as runner in my gitlab and tried to execute my scripts there.
While executing I got an error for database connection
Issue : java.sql.SQLRecoverableException: IO Error: The Network Adapter could not establish the connection
When I connect from my local machine (Windows 7 & 10) it is working fine.
Attempts:
Tried to connect using jtds but I'm getting some other unknown issue.
Checked few other answers and they have provided that it could be because of firewall enabled but since we did not have full access to that db server , I could not disable and check.(Could this be the issue?)
My Connection code :
ConURL = "jdbc:oracle:thin:#" + ConstructSQLConnectionURL(host,sid,port);
Class.forName("oracle.jdbc.driver.OracleDriver");
con = DriverManager.getConnection(ConURL, dbUserName, dbPassword);
I am stuck with this issue and blocked from executing pipeline.
Can anyone let me know what could be the possible reason for this and help me with this?
Thanks in advance

It appears to be a network connectivity issue. I'd start with local firewalls on each system. Can you ping the database from the client? If not, look for network routing or firewall blockers. Also look at host-based firewalls, or confirm with the DBA whether there is something like valid node checking in place to limit database clients.

Connect Metabase to Sql Server

I installed Java on my Windows 10 machine and downloaded Metabase.jar, and ran it.
Now I could access metabase at localhost:3000
But I'm unable to setup my SQL Server Database as Data reference.
I'm either getting:
Couldn't connect to the database. Please check the connection details.
or
Timed out after 5000 milliseconds.
Anyone who has done Metabase - SQL Server connection successfully?

Currently, as of Metabase version 0.30.x the answer depends on if you can use a user configured directly on SQL Server or not:
The easier option to setup is with a user configured directly on SQL Server. Then config is just Name: (anything), Host: (full name), Database Name, Username, Password as you would expect. (I believe you should NOT fill in the Windows domain).
On Windows only you can also use native integrated authentication with sqljdbc_auth.dll, just specify integratedSecurity=true connection property (and optionally authenticationScheme=NativeAuthentication). I found if I dropped the x64 sqljdbc_auth.dll in my <java path>\jre\bin folder it was picked up. Metabase config as in the screenshot below, apart from dropping authenticationScheme=JavaKerberos
The cross platform authenticationScheme=JavaKerberos option to use Windows Authentication with a domain user is still doable, but harder. It's these steps:
Create a krb.conf and verify login works with <Java path>\bin\kinit.exe [user]. Here's a template edited to match the Metabase database setup in the screenshot below.
Start the Metabase.jar file with parameters to load the krb.conf. It works for me with java -Djava.security.krb5.conf=c:/<path>/kerberos/krb.conf -jar metabase.jar.
Now configure the database settings in Metabase according to the screenshot below
Moment of truth! ...
Optional: Still not working? Maybe your SQL Server isn't configured for Kerberos? Maybe you need SPN setup? Maybe you need to specify a java.security.auth.login.config (I have not experienced any of that myself, only thing I can offer is you scroll to the bottom of this post and dive in then edit your question with where you got to and what config you have)
Metabase SQL Server setup using Kerberos:
For background, current (August 2018) very long :| sum up with lots of links of how to connect to SQL Server is here in a Metabase discussion topic Note: In v0.30.0 an issue with dynamic port handling (particularly for people using named instances) was fixed.
Related: A neat StackOverflow answer on Kerberos on a Mac

If you are connecting to a "Named Instance" ({SERVER_NAME}/{INSTANCE_NAME}) instead of "Default Instance" ({SERVER_NAME}), your server may be configured to use Dynamic Port.
A quick dirty fix is you can find the current port with below scripts and then use it on Metabase connection parameters. But this port most probably will change when service restart occurs.
SELECT DISTINCT
local_tcp_port
FROM sys.dm_exec_connections
WHERE local_tcp_port IS NOT NULL
or
USE master
GO
Xp_readerrorlog
(look for "Server is listening on ..." line)
A Cleaner way is setting port for your instance by "SQL Server Configuration Manager" - "SQL Server Network Configuration" - "TCP/IP" - Right Click properties - "TCP Dynamic Ports" (There should be 0 and it should be deleted) and "TCP Port" (New default port should be set here). And also "SQL Server Browser" service should run. A more detailed explanation is here

Error connecting to Oracle database using JDBC [duplicate]

I am new to Oracle, and am trying to run a simple example code with Java, but am getting this error when executing the code.. I am able to start up the listener via CMD and am also able to run SQL Plus. Can anyone give me a hand and tell me what I might be doing wrong?
Update:
I am using JDBC.
Database is local, and I actually had it working but it stopped working just today. I'm not really sure why though. Would you mind giving me some procedures to follow by since I don't know much.

Either:
The database isn't running
You got the URL wrong
There is a firewall in the way.
(This strange error message is produced by Oracle's JDBC driver when it can't connect to the database server. 'Network adapter' appears to refer to some component of their code, which isn't very useful. Real network adapters (NICs) don't establish connections at all: TCP protocol stacks do that. It would have been a lot more useful if they had just let the original ConnectException be thrown, or at least used its error message and let it appear in the stack trace.)

I had the same problem, and this is how I fixed it.
I was using the wrong port for my connection.
private final String DB_URL = "jdbc:oracle:thin:#localhost:1521:orcll"; // 1521 my wrong port
go to your localhost
(my localhost address) : https://localhost:1158/em
login
user name
password
connect as --> normal
Below 'General' click on LISTENER_localhost
look at you port number
Net Address (ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1522))
Connect to port 1522
Edit you connection
change port 1521 to 1522.
done

Another thing you might want to check that the listener.ora file matches the way you are trying to connect to the DB. If you were connecting via a localhost reference and your listener.ora file got changed from:
HOST = localhost
to
HOST = 192.168.XX.XX
then this can cause the error that you had unless you update your hosts file to accommodate for this. Someone might have made this change to allow for remote connections to the DB from other machines.

I figured out that in my case, my database was in different subnet than the subnet from where i was trying to access the db.

I had this error when i renamed the pc in the windows-properties. The pc-name must be updated in the listener.ora-file

Most probably you have listener configured wrongly, the hostname you specify in connection string must be the same as in the listener.
First check the Firewall and network related issues.
Check if Oracle Listener service is available and running. If not you may use Oracle Net Configuration Assistant tool to add and register new listener.
If the above steps are ok then you need to configure Oracle Listener appropriately. You may use Oracle Net Manager tool or edit “%ORACLE_HOME%\network\admin\listener.ora” file manually.
There are 2 options that need to be considered carefully:
Listening Locations associated with the Listener – Hostname(IP) and Port in Listening Location must exactly match the ones used in the connection string.
For example, if you use 192.168.74.139 as target hostname, then there must be Listening Location registered with the same IP address.
Also make sure the you use the same SID as indicated in Database Service associated with the Listener.
https://adhoctuts.com/fix-oracle-io-error-the-network-adapter-could-not-establish-the-connection-error/

IO Error: The Network Adapter could not establish the connection (CONNECTION_ID=iKQM6lBbSLiArrYuDqud8A==)
if you are facing this issue
1- make sure you have downloaded oracle databases like oracle 11g,19c, 21c, or any latest databases.
2- search for services in your computer or type win+r then services.mis then search for oracleservice you will find orcl or xe or any other sid like oracleserviceorcl;
after that you can test your connection using sql developer, sql plus or cmd

To resolve the Network Adapter Error I had to remove the - in the name of the computer name.

In my case, I needed to specify a viahost and viauser. Worth trying if you're in a complex system. :)

For me the basic oracle only was not installed. Please ensure you have oracle installed and then try checking host and port.

I was having issues with this as well. I was using the jdbc connection string to connect to the database. The hostname was incorrectly configured in the string. I am using Mac, and the same string was being used on Windows machines without an issue. On my connection string, I had to make sure that I had the full url with the appending "organizationname.com" to the end of the hostname.
Hope this helps.

Just try to re-create connection. In my situation one of jdbc connection stopped working for no reason. From console sqlplus was working ok.
It took me 2 hours to realize that If i create the same connection - it works.

Connecting to derby via I.P. Address fails

When I print the I.P. address of the system using InetAddress.getLocalHost(), I get user-VAIO/192.168.1.3 . Now, when I connect to derby using jdbc:derby://localhost:1527/mydatabase;create=true, it connects without any errors but when I connect the same using jdbc:derby://192.168.1.3:1527/mydatabase;create=true, it fails giving me the following exception:-
java.net.ConnectException : Error connecting to server 192.168.1.3 on port 1527 with message Connection refused: connect.
Any help will be appreciated.

When you start your Derby Network Server, you provide a value for the '-h' argument. You might not realize you are doing this, if you are using the packaged StartNetworkServer.bat file, but look inside the batch file, and you will see the -h argument there.
The batch file comes provided with the syntax '-h default' when you download Derby from the Apache website.
But you can change that, to say, for example, '-h 192.168.1.3', and then your Derby Network Server will accept connections that specify 'jdbc:derby://192.168.1.3/my/database'.
Note that if you want to accept such connections from other computers on the network, you will also have to adjust your Windows Firewall rules, as by default it will prevent such connections.

jdbc.SQLServerException: Login failed for user for any user

I trying to test the connection with my local sql DB. I have this code:
try{
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver").newInstance();
DriverManager.getConnection("jdbc:sqlserver://localhost:1433;databaseName=SocialFamilyTree;user=SOSCOMP");
}catch(Exception e){
System.out.println("Couldn't get database connection.");
e.printStackTrace();
}
I tried many users. my windows user is SOSCOMP and doesn't have a password. I also know that SQL 2008 create users as "sys" "dbo", I tried these too. I'm always getting:
Couldn't get database connection.
com.microsoft.sqlserver.jdbc.SQLServerException: Login failed for user 'SOSCOMP'.
at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDatabaseError(SQLServerException.java:196)
at com.microsoft.sqlserver.jdbc.TDSTokenHandler.onEOF(tdsparser.java:246)
at com.microsoft.sqlserver.jdbc.TDSParser.parse(tdsparser.java:83)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.sendLogon(SQLServerConnection.java:2532)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.logon(SQLServerConnection.java:1929)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.access$000(SQLServerConnection.java:41)
at com.microsoft.sqlserver.jdbc.SQLServerConnection$LogonCommand.doExecute(SQLServerConnection.java:1917)
at com.microsoft.sqlserver.jdbc.TDSCommand.execute(IOBuffer.java:4026)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.executeCommand(SQLServerConnection.java:1416)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectHelper(SQLServerConnection.java:1061)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.login(SQLServerConnection.java:833)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connect(SQLServerConnection.java:716)
at com.microsoft.sqlserver.jdbc.SQLServerDriver.connect(SQLServerDriver.java:841)
at java.sql.DriverManager.getConnection(DriverManager.java:579)
at java.sql.DriverManager.getConnection(DriverManager.java:243)
at FT_Receiver.FT_Receiver.main(FT_Receiver.java:12)
Any ideas?
Thanks

If you try to connect with database which is using windows authentication, you can use 'integratedSecurity' option in your connection string.
DriverManager.getConnection("jdbc:sqlserver://localhost:1433;databaseName=SocialFamilyTree;integratedSecurity=true;");

Having been through this very recently the steps I took to solve pretty much the same problem were
use SQL Server Management Studio to log in with the desired account and confirm access to read (and write if necessary)
Use SQL Server Configuration Manager to confirm that the server instance is listening on the IP address being targetted
Disable the firewall to check that isn't getting in the way (and add an exception if necessary for future use)
The absolute kicker for me was understanding what IP addresses and ports the instance was set to listen on so that when I constructed the connection string the connection wasn't being rejected.
Also, if you want to connect using Windows logins you need to ensure the SQL instance is configured for mixed mode authentication (i.e. to allow Windows and SQL logins)

Since you get this error,the Sql server correctly listens to the port.
Open Sql Server Management Studio connect to your Server.
right click on the server's icon and choose properties.
Go to the security tab and tick Sql Server and Windows
Authentication mode.
If you want to define a user,go from the tree, to Security->Logins,right click on logins folder and click "New Login".
Now your server should work with this Url String.
Use the log file of the Server that may help you understand its working.

Re: Did it. still WARNING: Failed to load the sqljdbc_auth.dll cause :- no sqljdbc_auth in java.library.path – Mike Oct 7 at 14:03
you have to add the path to sqljdbc_auth.dll by adding this under VM arguments in Eclipse or commandline if you're running from the shell:
-Djava.library.path="\MS SQL Server JDBC Driver 3.0\sqljdbc_3.0\enu\auth\x86"
that's if you're running 32 bit Windows. else the final subdir changes accordingly.
I think this might be a better answer though, to setting up SQL Server user based authentication:
Connecting SQL Server 2008 to Java: Login failed for user error
(I try to summarize it here: http://silveira.wikidot.com/sql-server)

I also faced the same issue, In my case the following things are configured wrongly
Two SQL (versions) servers are running in my system --> Sol: Please check ourselves which server we are pointing.
Ports are configured as dynamic --> Sol: we should set port 1433 and dynamic port should be 0, if we are connected to specific port.
While creating the new login (user) I have selected the option " change password after first login "--> Sol: we should not select this option while creating the new login, if we are trying connecting from some other service like Openfire.