The Network Adapter could not establish the connection when connecting with Oracle DB

Question

When trying to connect with a remote Oracle database via JDBC I receive the following exception   java sql SQLRecoverableException  IO-fout  The Network Adapter could not establish the connection at oracle jdbc driver T4CConnection logon T4CConnection java 419  at oracle jdbc driver PhysicalConnection  lt init gt  PhysicalConnection java 536  at oracle jdbc driver T4CConnection  lt init gt  T4CConnection java 228  at oracle jdbc driver T4CDriverExtension getConnection T4CDriverExtension java 32  at oracle jdbc driver OracleDriver connect OracleDriver java 521  at java sql DriverManager getConnection DriverManager java 322  at java sql DriverManager getConnection DriverManager java 358    The following is my set-up   Database  Oracle 10g Release 2 Standard Edition  JDBC library  ojdbc6 jar JDBC driver  oracle jdbc driver OracleDriver JDBC URL  jdbc oracle thin  9 2 2 2 1521 ORCL where ORCL is database s SID JDBC User pwd  Correct username   password   Strange about this problem is that the connection works just fine when I work from work  When I try to connect however from home via an AT amp T VPN connection  it doesn t work   I have confirmed that I can reach the IP address and have also telnetted the ip on port 1521  which works just fine  Connecting to the datasource from a local WebLogic Application Server also works alright  Furthermore  when trying to connect to the database via sqldeveloper I can also reach the database   I need to reach the database however from a standalone application  for testing purposes   Does anyone have an idea why this problem occurs  And whether there are alternatives for connecting to a remote Oracle Database  alternatives which sqldeveloper and weblogic perhaps use   Here s an excerpt of the code attempting to connect with the database   public static void main String args    throws ClassNotFoundException  SQLException       Class forName  oracle jdbc driver OracleDriver        Connection conn   DriverManager getConnection  jdbc oracle thin  9 2 2 2 1521 ORCL    user    pwd

User · Answer

If it is on a Linux box  I would suggest you add the database IP name and IP resolution to the  etc hosts   I have the same error and when we do the above  it works fine

User · Answer

Take a look at this post on Java Ranch   http   www coderanch com t 300287 JDBC java Io-Exception-Network-Adapter-could   The solution for my  Io exception  The Network Adapter could not establish the connection  exception was to replace the IP of the database server to the DNS name

User · Answer

When a client connects to an Oracle server  it first connnects to the Oracle listener service  It often redirects the client to another port  So the client has to open another connection on a different port  which is blocked by the firewall   So you might in fact have encountered a firewall problem due to Oracle port redirection  It should be possible to diagnose it with a network monitor on the client machine or with the firewall management software on the firewall

User · Answer

I had similar problem before  But this was resolved when I started using hostname instead of IP address in my connection string

[java] The Network Adapter could not establish the connection when connecting with Oracle DB

Examples related to java

Examples related to oracle

Examples related to exception

Examples related to jdbc