ERROR: Invalid Agent: Could not get agent for the realm

Sometimes, when CDSSO is configured, one will encounter HTTP Status 500 after a successful login.

1. Access protected application 

2. Redirect to OpenSSO Login Page

3. Upon successful login, redirect back to protected application

Step 3 is not happening. Instead, user encounters HTTP Status 500.

If you take a look at the amAgent log on the protected application side, there is nothing unusual. All seems good. 

Something is definitely wrong on the OpenSSO server end. 

The problem is "Unknown Host Exception".  Add the FQDN to the /etc/hosts resolves the issue!

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