I am trying to set up Sitecore 9.1.1 Identity Server to act as a Federation Gateway with Azure AD (described here - https://doc.sitecore.com/developers/91/sitecore-experience-management/en/use-the-sitecore-identity-server-as-a-federation-gateway.html). What isn't clear to me is how to register the Sitecore site in Azure AD. I am assuming that in Azure AD you have to configure a Redirect URI or some sort of Reply URL to tell Azure AD where to go after successful authentication. The Sitecore documentation doesn't really specify.
In the Sitecore documentation it links you to this for configuring Azure AD (https://docs.microsoft.com/en-us/azure/active-directory/develop/v1-protocols-openid-connect-code). In that documentation it says "Provide the Redirect URI. For Web Applications, this is the base URL of your app where users can sign in." That leads me to believe that the Redirect URI should be
https://[SI Server Host Name]/account/login since that is the page I go to when I want to log in. However the Sitecore documentation also makes mention of this URI -
https://[SI Server Host Name]/signin-oidc. I have no idea at all what that /signin-oidc thing is. When I try to go to that on my Identity Server I get a 404 error.
Does anyone know exactly what I should put in ADFS for the Redirect URI? Also the Sitecore documentation mentions the ReplyURLs setting in the Application Manifest. Although it isn't clear what they mean by that I am guessing they mean the Application Manifest in the Azure AD setup.