Pre-requisites: SAML2 enabled, RDBMS security store enabled, WL configured as SAML2 SP.
1. Add new IdP partner from Security Realm > Providers > Authentication > SAML2 Identity Assertion Provider > Management > New Web Single Sign-On Identity Provider Partner
2. Choose the given IdP metadata XML and click on OK
3. Go to the newly created IdP
4. Tick on Enabled and assign protected URIs, .e.g: /protected/123/*
5. Click on Save
6. Use browser or other HTTP client/tool to access http://<BASE_URI>/protected/123/*
7. Request will not get redirected to IdP published URL, instead it will go directly to the servlet which is mapped to the context root. (Wait for some more time to let WLS read the settings from DB)
8. If it does not gets redirected then Restart all managed servers
9. Retry and the request will get redirected to IdP.