IO Exception :NetWork Adapter could not establish the connection

[Tarun Basandra]

last few days , i am facing below error in prodcution enviroment
Io exception: The Network Adapter could not establish the connection
java.sql.SQLException: Io exception: The Network Adapter could not establish the connection
at oracle/jdbc/dbaccess/DBError.throwSqlException
at oracle/jdbc/dbaccess/DBError.throwSqlException
at oracle/jdbc/driver/OracleConnection.<init>
Application is j2ee based using weblogic as application server. this application is quite stable & after seeing the logs for last two years , it shows this error comes & usually after three four seconds application itself again regain the connection . but for the last few days i had faced this error which continues till i need to restart the server .
Is this error due network problems or any shortcoming with oracle thin driver or Weblogic problem.
if somebody had any idea about it , please help it urgent as this problems comes in production server.

[Manish Agarwal]

Hi Ranchers,

I have one query related to the error "IO Exception :NetWork Adapter could not establish the connection".
I was getting this error yesterday, I tried everything, my code was correct as it was working perfect on other machine...and I have added all required environment variables....I tried using name and IP address of the database but still I was getting this error. Then I added an entry of IP address with database name in the host file and it started working. I dont understand why my code was reading the host file. And as far as I know host file is just for mapping the IP address with database name.
Can anyone please explain this?

Thanks,
Manish Agarwal