Azure GateWay SAML Authentication Error

Question

When using SAML and as an Azure IDP, we have the following situation:
2 Servers for high availability that are balanced by an Azure Gateway.

When trying to access the url generated by the gateway e.g.
https://servidorbalanceado.red.empresa.com.co, it tries to authenticate with SAML, but returns the following error:

AADSTS50011: The reply URL specified in the request does not match the reply URLs configured for the application:

https://servidorbalanceado.red.empresa.com.co/shibboleth

But if I try to log in, using each of the servers, if I succeed in connecting to

https://servidor1.red.empresa.com.co
https://servidor2.red.empresa.com.co

I ask for your help, because I think the problem is in the way the gateway makes the call of the balanced url's, but I don't know how to solve it.

Thanks

Answer 1

HEllo @Yackeline España Arevalo (DCA TECHNOLOGY LTDA) , Thank you for reaching out. Can you please provide more details on how the listeners is configured in your scenario? Also have you set any URL rewrite rules in this scenario?
I think the host name of request being sent from application gateway to your backend is wrong. Can you please check what is the hostname received in backend? if there is a mismatch can you please configure the host name in AAD as mentioned here.