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Azure SQL database connection issue from an Azure VM by Java JDBC

We have a java project in an Azure virtual machine (VM), and need connect to Azure SQL db by JDBC connection, so we use the JDBC connection string provided by Azure SQL db as follows:
"jdbc:sqlserver://ZZZdbserver.database.windows.net:1433;database=ZZZ;user=*****;password=*****;encrypt=true;trustServerCertificate=false;hostNameInCertificate=*.database.windows.net;loginTimeout=30;"
but we got an exception:
"java.security.cert.CertificateException: Failed to validate the server name in a certificate during Secure Sockets Layer (SSL) initialization.
The server name is *.database.windows.net, the name in certificate is cr2.eastus1-a.control.database.windows.net."
then we updated the JDBC connection string to:
"jdbc:sqlserver://ZZZdbserver.database.windows.net:1433;database=ZZZ;user=*****;password=*****;encrypt=true;trustServerCertificate=false;hostNameInCertificate=cr2.eastus1-a.control.database.windows.net;loginTimeout=30;"
but we got another exception:
org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Cannot open server "ZZZ1" requested by the login. The login failed.)
where "ZZZ1" is our username for the Azure VM.
Any idea to solve this issue?

By default, Azure VM has not blocked the outbound connection to the Internet. You could first verify the network connectivity from your VM to the Azure SQL database via running the command telnet ZZZdbserver.database.windows.net 1433 in CMD or Test-NetConnection -computer ZZZdbserver.database.windows.net -port 1433 in Powershell. If it fails, you may check if there is any firewall blocking this database connection or port or your application is listening on that port or your SQL database is online.
Additionally, if the network connectivity has succeeded, you could verify if the username or password is correct when you are using to connect to your database. Make sure there is not any typo. Also, the username should have enough privileges to access this database. You can try to access this database via Server admin login in the properties of the SQL database. Moreover, you could refer to this sample code to use Java to connect to access the Azure SQL database.
When using the Microsoft JDBC Driver for SQL Server to connect to an Azure SQL Database. You should note this:
Appending the server name to the userId in the connection string
Prior to the 4.0 version of the Microsoft JDBC Driver for SQL Server,
when connecting to an Azure SQL Database, you were required to append
the server name to the UserId in the connection string. For example,
user#servername. Beginning in version 4.0 of the Microsoft JDBC Driver
for SQL Server, it's no longer necessary to append #servername to the
UserId in the connection string.
Using encryption requires setting hostNameInCertificate
Prior to the 7.2 version of the Microsoft JDBC Driver for SQL Server,
when connecting to an Azure SQL Database, you should specify
hostNameInCertificate if you specify encrypt=true (If the server name
in the connection string is shortName.domainName, set the
hostNameInCertificate property to *.domainName.). This property is
optional as of version 7.2 of the driver.
Hope this helps.

If I need set encrypt=true, and hostNameInCertificate=cr2.eastus1-a.control.database.windows.net. Where do I need get the certificate for cr2.eastus1-a.control.database.windows.net from Azure SQL DB's service?

I can connect to AWS MySQL RDS instance from workbench but not in my JDBC application

I am trying to create a Java application that connects to a MySQL database and I am using AWS to host it. So I created the AWS RDS instance and I got it to connect to the MySQL workbench just fine. My problem arises when I am trying to use JDBC to connect to it.
I have security groups that allow traffic from anywhere, but I also tried just allowing my IP.
I had it working when I was using a localhost but now I'm trying to move it to a server so keeping it localhost isn't an option (used localhost to test the application and such)
I made sure that my user was a remote user by doing
SELECT * from mysql.user;
And made sure that the host was a '%' and that it had all the privileges
So my code I'm trying to connect with in Java is
String connectionURL = "jdbc:mysql:/{hostname}:{port}/{database name}/?autoReconnect=true&useSSL=false";
String username = "username";
String password = "password";
con = DriverManager.getConnection(connectionURL, username, password);
Of course I have the actual host, port, and such in there just changed it for posting online.
When I try running it on Eclipse it says this java.lang.Exception: Database not found
I looked up some tutorials on AWS docs to make sure it lined up, which it all did.
Anyone have any idea why it might be connecting to MySQL workbench and not the JDBC?

Access denied when trying to connect to mysql database via eclipse, java

I'm trying to connect to mysql database, but I get one and the same error: javax.servlet.ServletException: java.sql.SQLException: Access denied for user 'user'#'localhost' (using password: YES)
I've already tried the following solutions:
Checked my username and password. MySQL connection is established via username = user1, password = 123. I use the same in my code, when I connect to the database: Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = DriverManager.getConnection(
"jdbc:mysql://localhost:3306/employee","user1", "123");
Granted privileges to user1 in the following manner:
GRANT ALL PRIVILEGES ON * . * TO 'user1'#'localhost';
FLUSH PRIVILEGES;
By the way I have the same problem when I try to connect with 'root'#'localhost'.
Do you have any ideas why it doesn't work still?

MySQL JDBC is only able to connect via TCP/IP (on Unix, or TCP/IP or named pipe on Windows).
The MySQL JDBC driver cannot establish a connection using the local unix socket.
With MySQL on Unix, localhost has a different meaning that we might expect. It is not a hostname synonym for the 127.0.0.1 TCP/IP loopback address. On Unix, MySQL user
'user1'#'localhost'
specifies a user that can connect only via unix socket file; it's not possible to connect to that user via TCP/IP.
The above explains why MySQL is refusing a connection from JDBC: the connection attempt fails because a matching user does not exist.
To create a MySQL user that connect from TCP/IP loopback address, assuming that MySQL is started with --skip-name-resolve and without --skip-networking, we can specify user as:
'user'#'127.0.0.1'
That user would allow connection from JDBC.
(If MySQL DNS name resolution is enabled, then we would need to use a hostname that resolves to the loopback address; or we can consider using a wildcard '%' for the hostname portion of the user.)

Try this out might help:
1) goto mysql terminal. 2) mysql> use mysql; 3) mysql> select user, host from user; 4) There next to you user set the host as "%" instead of localhost
.
now in the connection instead of localhost tryp specifying the ip address of the server.
Hope this helps you. :)

connection string for phpMyAdmin database

If I have a mysql database on my own pc, I would use the following cnxn string to connect it to my java program :
String url = "jdbc:mysql://localhost:port/dbname";
But if my database is made over phpMyAdmin, what would be the connection string ?
one other note, the phpmyadmin database is not on my local pc now, it is on another one but both pc are in the same network.
Thanks for any help ..

phpMyadmin is administration web application developed on PHP platform. phpMyadmin connects to MySQL database that might be on other machine.
you need to check config.inc.php file of phpMyadmin to check the host and port of mysql database.
Once you get the IP and port of the mysql database you can connect using connect string like
jdbc:mysql://<ipaddress>:<port>/<database_created_through_phpMyAdmin>

Replace localhost with the IP of the machine that hosts your database:
String url = "jdbc:mysql://<ip_goes_here>:port/dbname";
As Rutesh mentions, this may or may not be the same machine on which phpMyAdmin runs.

what would be the database URL of the mysql database that we access through phpMyAdmin?

I am writing a code that access a MySql database. The database is on a server that we access through our web-browser
Let's say,
URL: http://cbm.goo.com/phpMyAdmin
Username: username
Password: password
The above username and password are used to access the MySql database through a web-browser.
Q1. What would be database url of the database to be used in JDBC programming?
I tried the following url but it didn't work
jdbc:mysql://cbm.goo.com:3306/scores?user=username&password=password
========================== Edited ===================================
I am getting the following error:
Communications link failure
The last packet successfully received from the server was 1,267,163,244,109 milliseconds ago. The last packet sent successfully to the server was 0 milliseconds ago.

Check that your internet connection is not going through some sort of firewall that is blocking access to port 3306.
Some companies have restricitions set on which ports can be used. Web servers use port 80 which is usually opened up to allow web browsing. Your MySQL server is using port 3306.

Using JDBC with MySQL quick start guide