1. Edit the file $ORACLE_HOME/discoverer/util/pref.txt.
2. Under the heading [Session Manager] there is a parameter called timeout.
Timeout = 1800 (Number of Seconds before timeout)
3. Save the pref.txt file.
4. Run the applypreferences script.

When changing the timeout value to be higher than 30 minutes you will need to change the Discoverer servlet timeout as well. The servlet timeout must always be higher or equal to the Discoverer session timeout.Steps to change the Discoverer Servlet timeout:

1. Edit the following file:

2. Add the following entry to the file:
<!– Session timeout in minutes –>
<session-timeout>60 </session-config> The file should look something like:

3. Save the web.xml file.
4. Run command ’dcmctl updateConfig -ct oc4j -v’ to update the configuration.
5. Restart the whole thing with opmnctl stopall and opmnctl startall. Just do it.