Currently I have a BW sysem with EP that is in a mycompany.com domain and I have a new ECC system which is in a mycompany.lan domain. What I am trying to do is access some screens from the ECC system via WebGUI within the BW EP. I have followed the help section and added the ECC system to the UME properties and then imported the BW cert into SAPTRUSTSSO2 in ECC and have also added the ECC cert into the BW portal. I have also adjusted the necessary profile parameters for SSO. After all of this SSO still does not work. Is it possible to have SSO between multiple domains in this scenario? The scenarios listed in the help are a bit different than what I am doing. Thanks.
Please make sure ECC certificate is added to ACS in portal and BW certificated added into ECC ACS in both client 000 and production client. Please have a look at the below document for more details.
It should resolve your problem.
SSO between multiple domain is possible using mysapsso2 cookie approach.
refer the below link: