Using the Existing DummyClientTrustFile.jks and DummyClientKeyFile.jks files
When you are registering a brand new WAS Instance from the Server Manager Console, you can keep the TrustStore File, TrustStore File Password, KeyStore File, and KeyStore File Password as blank.

If you have already registered a WAS Instance and would like to use the default DummyClientTrustFile.jks and DummyClientKeyFile.jks files from the <profile>/etc. folder like the pre 9.2 Tools Release, then you will need to:
Open the registered WAS instance page.
In the Instance Properties section (top right), blank out or clear the TrustStore File and KeyStore File fields.
Click the Save button next to these fields.
Restart the Server Manager Agent.
Server Manager will now start using the default DummyClientTrustFile.jks and DummyClientKeyFile.jks files from the <WASInstall>/AppServer/profiles/<profile>/etc folder, as it would in the pre 9.2 Server Manager.